METHOD FOR ADJUSTING OVERCURRENT IN ENERGY STORAGE SYSTEM AND ENERGY STORAGE SYSTEM

Abstract

The present application provides an overcurrent adjustment method for an energy storage system and an energy storage system, the method includes: obtaining a current value and an overcurrent capacity of each battery cluster among a plurality of battery clusters; determining an overcurrent value of each battery cluster according to the current value and the overcurrent capacity; determining a maximum overcurrent value among the overcurrent values ​​of the plurality of battery clusters; and adjusting a total current limit value of the energy storage system according to the maximum overcurrent value. The method can dynamically adjust the current of the energy storage system and effectively solve the overcurrent problem of the energy storage system.

Description

[Technical field]

[0001] The present application relates to the field of energy storage technology, and in particular to an overcurrent regulation method for an energy storage system and an energy storage system. [Background technology]

[0002] In the energy storage system, the battery clusters are connected in parallel, and the internal resistance of each battery cluster is different, so the current during charging and discharging is different. Due to serious current imbalance of the battery clusters, the current of the battery cluster with small internal resistance is large, which is easy to trigger overcurrent, and the battery cluster operates in an overcurrent state for a long time, which increases the risk of lithium precipitation in the battery core.

[0003] Therefore, how to effectively solve the overcurrent problem in the energy storage system is currently an issue that urgently needs to be resolved. Summary of the Invention

[0004] The present application provides an overcurrent adjustment method for an energy storage system and an energy storage system, which can dynamically adjust the current of the energy storage system and effectively solve the overcurrent problem of the energy storage system.

[0005] According to a first aspect, there is provided a method for regulating an over-current of an energy storage system including a plurality of battery clusters connected in parallel, the method including: obtaining a current value and an over-current capability of each battery cluster among the plurality of battery clusters; determining an over-current value of each battery cluster based on the current value and the over-current capability; determining a maximum over-current value among the over-current values ​​of the plurality of battery clusters; and adjusting a total current limit value of the energy storage system based on the maximum over-current value.

[0006] The present application determines the overcurrent value of the battery cluster according to the current value and overcurrent capacity of the battery cluster, takes the maximum value of the overcurrent values ​​of the multiple battery clusters as the maximum overcurrent value, and adjusts the total current limit value of the energy storage system according to the maximum overcurrent value, so that when the maximum overcurrent value is large, the total current limit value of the energy storage system can be adjusted in a timely manner to avoid the overcurrent damage caused by the excessive current in the battery cluster of the energy storage system, and thus the safe operation of the battery cluster of the energy storage system can be protected. At the same time, this method of solving the overcurrent problem by adjusting the total current limit value of the energy storage system according to the maximum overcurrent value does not require additional hardware to adjust the battery cluster of each branch circuit respectively, so that the integration cost of the system can be reduced, and the overcurrent problem of the energy storage system can be effectively solved.

[0007] In one possible implementation, adjusting the total current limit value of the energy storage system based on the maximum overcurrent value includes lowering the total current limit value if the maximum overcurrent value is greater than a first threshold, where the first threshold is a preset value greater than zero.

[0008] By setting the first threshold, the total current limit value of the energy storage system can begin to be reduced when the maximum overcurrent value of the energy storage system exceeds the first threshold, thereby realizing overcurrent protection of the energy storage system.

[0009] In one possible implementation, lowering the total current limit value includes gradually lowering the total current limit value until the maximum overcurrent value is equal to or less than a second threshold value, where the second threshold value is less than a preset value of the first threshold value.

[0010] In the method of reducing the total current limit value, a gradual reduction method is adopted, so that the total current limit value of the energy storage system is gradually reduced, and it is possible to avoid the total current limit value being reduced too quickly, which causes the current of the energy storage system to change rapidly and damage the performance of the battery cluster. As the total current limit value decreases, the maximum overcurrent value calculated in real time also gradually decreases, but by setting the second threshold value, the reduction of the total current limit value can be stopped when the maximum overcurrent value is equal to or less than the second threshold value, so that the energy storage system can have a large working current and maintain high power when there is no overcurrent.

[0011] In one possible implementation, the second threshold is 0. When the second threshold is set as 0, that is, when the maximum overcurrent value is less than or equal to 0, that is, when there is no overcurrent in the battery cluster of each branch circuit of the energy storage system, the total current limit value of the energy storage system is stopped from being lowered, thus ensuring that the energy storage system maintains a large working current in a timely manner after eliminating the overcurrent problem.

[0012] In one possible implementation, adjusting the total current limit value of the energy storage system based on the maximum overcurrent value includes increasing the total current limit value if the maximum overcurrent value is less than a third threshold, where the third threshold is a preset value less than zero.

[0013] By setting the third threshold, the total current limit value of the energy storage system can begin to increase when the maximum overcurrent value of the energy storage system is less than the third threshold, thereby allowing the energy storage system to operate at a large operating current in the absence of an overcurrent.

[0014] In one possible implementation, increasing the total current limit value includes incrementally increasing the total current limit value until the maximum overcurrent value is greater than or equal to a fourth threshold, where the fourth threshold is greater than the third threshold.

[0015] The method for increasing the total current limit value is a stepwise increase method, which gradually increases the total current limit value of the energy storage system, thereby avoiding the current of the energy storage system changing too quickly due to the total current limit value being increased too quickly, which can damage the performance of the battery cluster. As the total current limit value increases, the maximum overcurrent value calculated in real time also gradually increases, but by setting a fourth threshold value, the increase in the total current limit value can be stopped when the maximum overcurrent value is equal to or greater than the fourth threshold value, thus avoiding the occurrence of an overcurrent due to the total current limit value being increased too much by the energy storage system.

[0016] In one possible implementation, the fourth threshold is −2 A. Setting the fourth threshold as −2 A aims to avoid raising the total current limit value of the energy storage system too much, while ensuring that the energy storage system has a high working current.

[0017] In one possible implementation, the overcurrent value of each battery cluster is a difference value obtained by subtracting the overcurrent capability of each battery cluster from the current value of each battery cluster.

[0018] According to a second aspect, there is provided an energy storage system, the system including: a plurality of battery clusters connected in parallel; a plurality of current sensors for respectively obtaining a current value of each battery cluster among the plurality of battery clusters; a plurality of sub-control units for obtaining a current value of each battery cluster among the plurality of battery clusters from the plurality of current sensors; and a main control unit for adjusting a total current limit value of the energy storage system based on a maximum overcurrent value among the overcurrent values ​​of the plurality of battery clusters, where the overcurrent value of each battery cluster is determined based on the current value of each battery cluster and the overcurrent capability of each battery cluster.

[0019] In one possible implementation, the main control unit is used to reduce the total current limit value when the maximum overcurrent value is greater than a first threshold, where the first threshold is a preset value greater than zero.

[0020] In one possible implementation, the main control unit is used to gradually reduce the total current limit value until the maximum overcurrent value is equal to or less than a second threshold value, where the second threshold value is smaller than a preset value of the first threshold value.

[0021] In one possible implementation, the second threshold is zero.

[0022] In one possible implementation, the main control unit is used to increase the total current limit value when the maximum overcurrent value is less than a third threshold, where the third threshold is a preset value less than zero.

[0023] In one possible implementation, the main control unit is used to gradually increase the total current limit value until the maximum overcurrent value is equal to or greater than a fourth threshold, where the fourth threshold is greater than the third threshold.

[0024] In one possible implementation, the fourth threshold is −2A.

[0025] In one possible implementation, the overcurrent value of each battery cluster is a difference value obtained by subtracting the overcurrent capability of each battery cluster from the current value of each battery cluster.

[0026] According to a third aspect, there is provided an overcurrent adjustment device for an energy storage system, the device comprising: a memory for storing a computer program; and a processor for calling the computer program to cause the device to implement a method according to any one of the possible implementation manners of the first or second aspect.

[0027] According to a fourth aspect, there is provided a computer readable storage medium having stored thereon a computer program which, when executed by a computing device, causes the computing device to implement a method according to any one of the possible implementation manners of the first or second aspect above. [Brief description of the drawings]

[0028] In order to more clearly explain the technical solutions of the embodiments of the present application, the following will briefly describe the drawings that need to be used in the embodiments of the present application. It should be apparent that the drawings described below are only some embodiments of the present application, and those skilled in the art can obtain other drawings based on the drawings without exerting creative efforts. [Figure 1] FIG. 1 is a schematic diagram of an energy storage system according to an embodiment of the present application. [Diagram 2] 1 is a schematic flowchart of an overcurrent adjustment method for an energy storage system according to an embodiment of the present application. [Diagram 3] 4 is a schematic flowchart of an overcurrent adjustment method for an energy storage system according to another embodiment of the present application. [Figure 4] 1 is a schematic flowchart of an overcurrent adjustment method for an energy storage system according to an embodiment of the present application. [Diagram 5] 4 is a schematic flowchart of an overcurrent adjustment method for an energy storage system according to another embodiment of the present application. [Figure 6] 1 is a schematic flowchart of an overcurrent adjustment method for an energy storage system according to an embodiment of the present application. [Figure 7] 1 is a schematic diagram of an energy storage system according to one embodiment of the present application; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] In order to clarify the purpose, technical solutions and advantages of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly described below in conjunction with the drawings of the embodiments of the present application. It is clear that the described embodiments are only a part of the embodiments of the present application, and are not all of the embodiments. All other embodiments obtained based on the embodiments of the present application without the need for creative efforts by those skilled in the art are within the scope of protection of the present application.

[0030] In the description of this application, all technical and scientific terms used have the same meaning as commonly understood by those skilled in the art, unless otherwise indicated, as should be explained. The terms used are intended to describe specific embodiments and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above description of the drawings are intended to cover non-exclusive "including". "Plurality" means two or more. The orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "inner", "outer", etc., does not indicate or imply that the device or element shown must have a particular orientation or be configured and operated in a particular orientation, but is merely intended to facilitate and simplify the description of this application and should not be understood as a limitation of this application. In addition, terms such as "first", "second", "third", etc. are used for explanatory purposes only and should not be understood as indicating or implying relative importance.

[0031] An "embodiment" referred to in this application means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of this application. The appearance of the phrase in each location in the specification does not necessarily refer to all the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. Those skilled in the art can explicitly and implicitly understand that the embodiment described in this application may be combined with other embodiments.

[0032] Any directional terms appearing in the following description are directions shown in the drawings, and are not intended to limit the specific structure of the present application. In the description of the present application, it should be further explained that unless otherwise clearly specified and limited, the terms "attached", "connected" and "connected" should be understood in a broad sense, for example, they may be fixedly connected, detachably connected, or integrally connected, and may be directly connected or indirectly connected via an intermediate medium. For those skilled in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0033] The term "and / or" in this application merely describes the relationship between related objects and indicates that three relationships may exist, for example, A and / or B may represent three cases: A alone, A and B in combination, and B alone. Also, the character " / " in this application generally indicates that the related objects before and after are in an "or" relationship.

[0034] At present, energy storage systems are an important part of building smart grids, which can effectively realize the user's electric energy management, improve the reliability of system operation and power supply quality, and suppress the power fluctuation of renewable energy. In an energy storage system in which battery clusters are connected in parallel, the internal resistance of each battery cluster is different, so the current during charging and discharging is different. Due to serious current imbalance of battery clusters, the current of battery clusters with small internal resistance is large, which is easy to trigger overcurrent, and the battery clusters operate in an overcurrent state for a long time, which increases the risk of lithium precipitation in the battery core.

[0035] Currently, the current regulation method for the battery clusters of parallel branch circuits in an energy storage system mainly involves installing a direct current (DC / DC) converter in each branch circuit to independently control the current of the battery clusters of each branch circuit, and monitoring the overcurrent state of the battery clusters of each branch circuit through a feedback regulation circuit of each branch circuit. When an overcurrent occurs, the DC / DC of this branch circuit performs voltage compensation, and the total voltage of different branch circuits is maintained at the same level, thereby solving the current imbalance problem between the battery clusters of each branch circuit. However, this method requires the addition of a DC / DC and a feedback regulation circuit, which increases the integration cost of the system, and as the number of parallel branch circuits in the system increases, the requirement for the system's cooperative processing ability for the parallel branch circuits increases.

[0036] In view of this, an embodiment of the present application provides an overcurrent adjustment method for an energy storage system, which adjusts the total current limit value of the energy storage system based on the maximum overcurrent value of the battery clusters of the parallel branch circuits in the energy storage system. This method of adjusting the total current limit value of the energy storage system based on the maximum overcurrent value does not require additional hardware to adjust the battery clusters of each branch circuit respectively, thereby reducing the integration cost of the system and thereby effectively solving the overcurrent problem of the energy storage system.

[0037] FIG. 1 is a schematic diagram of an energy storage system 100 according to the present application.

[0038] The energy storage system 100 includes a plurality of battery clusters, such as battery cluster 1 to battery cluster m shown in FIG. 1, where m may be a natural number greater than 1; that is, in practical applications, the number of battery clusters can be flexibly adjusted based on the energy storage capacity; when the energy storage capacity is large, the number of battery clusters can be appropriately increased; and when the energy storage capacity is small, the number of battery clusters can be appropriately decreased.

[0039] Each battery cluster is configured by connecting at least two battery energy storage modules (ESS) in series, such as energy storage module 1 to energy storage module j shown in FIG. 1, where j may be a natural number equal to or greater than 2. Each energy storage module ESS is configured by connecting several energy storage elements in series or in parallel to form a minimum energy storage and management unit. In order to realize the detection and control of the energy storage system, a battery management system (BMS) is designed in each energy storage module and battery cluster to monitor battery information such as battery state of charge (SOC), temperature, and current, and exchange information with a higher-level energy management system (EMS) or power convert system (PCS) in real time to realize effective management and control of the entire battery energy storage system.

[0040] 2 is a schematic flow chart of an overcurrent regulation method for an energy storage system according to an embodiment of the present application. The energy storage system includes a plurality of battery clusters connected in parallel, and may be, for example, the energy storage system 100 in FIG. 1.

[0041] 201, obtaining a current value and an overcurrent capability of each battery cluster among a plurality of battery clusters.

[0042] The current value of the battery cluster may be obtained by a current sensor. A current sensor is installed in the battery cluster of each branch circuit, for example, one current sensor is connected in series to each battery cluster of each branch circuit, and the current sensor has a one-to-one correspondence with the battery cluster to obtain the current value of each battery cluster.

[0043] The overcurrent capability of the battery cluster may be calculated and obtained based on the parameters of the battery cluster itself. For example, based on parameters such as the temperature, SOC, and battery state of health (SOH) of the battery cluster, the overcurrent capability of the corresponding battery cluster is obtained by a table lookup method when the above parameters are certain specific values.

[0044] 202, determining an overcurrent value of each battery cluster according to the current value and the overcurrent capability.

[0045] For each battery cluster, an overcurrent value is determined based on the current value and the overcurrent capacity of the battery cluster. For example, the overcurrent value of each battery cluster may be a difference value obtained by subtracting the overcurrent capacity of each battery cluster from the current value of each battery cluster.

[0046] 203, determining a maximum overcurrent value among the overcurrent values ​​of the plurality of battery clusters.

[0047] The maximum overcurrent value is the maximum value among the overcurrent values ​​of the multiple battery clusters of the energy storage system.

[0048] 204, adjusting the total current limit value of the energy storage system based on the maximum overcurrent value.

[0049] Adjusting the total current limit value of the energy storage system according to the maximum overcurrent value can be to lower the total current limit value, or to raise the total current limit value, specifically, to dynamically adjust according to the situation of the maximum overcurrent value, based on which the current of each battery cluster changes correspondingly, so that the total current of the energy storage system tends to this total current limit value, thereby achieving the purpose of adjusting the current of each battery cluster.

[0050] In the embodiment of the present application, the total current limit value of the energy storage system is adjusted according to the maximum overcurrent value of the battery cluster, so that when an overcurrent occurs in the battery cluster of the energy storage system, the total current limit value can be reduced, so that the current of the battery cluster of each branch circuit is also reduced correspondingly, thereby solving the overcurrent problem of the battery cluster. At the same time, when the current of the energy storage system is small, the total current limit value can be increased, so that when there is no overcurrent, the energy storage system has a large working current and maintains high power. This method of solving the overcurrent problem by adjusting the total current limit value of the energy storage system according to the maximum overcurrent value does not need to adjust the battery cluster of each branch circuit respectively with additional hardware, so that the integration cost of the system can be reduced, and the overcurrent problem of the energy storage system can be effectively solved.

[0051] 3 is a schematic flow chart of an overcurrent adjustment method for an energy storage system according to another embodiment of the present application. 301-303 in FIG. 3 are similar to 201-203 in the above-mentioned embodiment, so please refer to the above-mentioned embodiment, and for the sake of brevity, will not be further described here.

[0052] 304, determining whether the maximum overcurrent value is greater than a first threshold value.

[0053] 305, if the maximum overcurrent value is greater than the first threshold, reduce the total current limit value of the energy storage system.

[0054] The first threshold refers to a preset first current parameter in the energy storage system, and may be a preset value greater than zero. If the maximum overcurrent value exceeds the first threshold, the total current limit value of the energy storage system is reduced. The current parameter of the first threshold may include a fixed value, a modifiable value, a value determined by a table lookup method, or a value determined by a correlation function, and the embodiments of the present application are not limited thereto. The first threshold may be a maximum overcurrent value at which no overcurrent damage occurs to the battery cluster in the energy storage system. For example, the first threshold may be 2A, so that the maximum overcurrent value of the battery cluster in the energy storage system may be controlled to be 2A or less.

[0055] If it is determined that the maximum overcurrent value is greater than the first threshold, the total current limit value of the energy storage system is reduced. If the maximum overcurrent value is equal to or less than the first threshold, the total current limit value of the energy storage system is not reduced, and the current value of each battery cluster is continued to be monitored.

[0056] In the embodiment of the present application, the total current limit value of the energy storage system is reduced based on the magnitude relationship between the maximum overcurrent value and the first threshold value. When an overcurrent occurs in a battery cluster of a branch circuit of the energy storage system and the maximum overcurrent value exceeds the first threshold value, the total current limit value of the energy storage system may be reduced, thereby realizing overcurrent protection of the energy storage system.

[0057] Optionally, in one embodiment of the present application, the total current limit value may be reduced in a stepwise manner. Specifically, the total current limit value may be reduced stepwise until the maximum overcurrent value is equal to or less than the second threshold value. Reducing the total current limit value stepwise means gradually reducing the total current limit value at a predetermined speed. Referring to FIG. 4, FIG. 4 is a schematic flow chart of an overcurrent adjustment method for an energy storage system according to one embodiment of the present application. 401-404 in FIG. 4 are similar to 301-304 in the previous embodiment, so reference may be made to the previous embodiment, and will not be further described here for the sake of brevity.

[0058] 405, if the maximum overcurrent value is greater than the first threshold, I d / sec to decrease the total current limit.

[0059] I d is the rate at which the total current limit is stepped down. d The value of may be preset or adjusted in real time, and the embodiments of the present application are not limited thereto.

[0060] 406, determining whether the maximum overcurrent value is greater than a second threshold value.

[0061] In the process of gradually lowering the total current limit value, the maximum overcurrent value of the energy storage system needs to be monitored in real time, and a second threshold is set to determine whether the energy storage system needs to continue lowering the total current limit value. That is, every time the total current limit value is lowered, the current value and overcurrent capability of each battery cluster need to be obtained again, and the overcurrent value and the corresponding maximum overcurrent value of each battery cluster need to be determined, that is, 401 to 403 need to be performed again. Then, it is determined whether the maximum overcurrent value is greater than the second threshold.

[0062] 407, if the maximum overcurrent value is greater than the second threshold, return to 405 and select I d / sec.

[0063] The second threshold refers to a second current parameter that is preset in the energy storage system and is smaller than the first threshold, for example, the second threshold may be 0, and the second threshold current parameter may include a fixed value, a modifiable value, a value determined by a table lookup method, or a value determined by a correlation function, and the embodiments of the present application are not limited thereto. If the maximum overcurrent value is equal to or less than the second threshold, the reduction of the total current limit value of the energy storage system is stopped.

[0064] In the embodiment of the present application, a gradual reduction method is adopted to gradually reduce the total current limit value of the energy storage system, thus avoiding the total current limit value being reduced too quickly, which causes the current of the energy storage system to change rapidly and damage the performance of the battery cluster. As the total current limit value decreases, the maximum overcurrent value calculated in real time also gradually decreases, but by setting the second threshold, the reduction of the total current limit value can be stopped when the maximum overcurrent value is equal to or less than the second threshold, so that the energy storage system can have a large working current and maintain high power when there is no overcurrent.

[0065] 5 is a schematic flow chart of an overcurrent adjustment method for an energy storage system according to another embodiment of the present application. 501-503 in FIG. 5 are similar to 401-403 in the above-mentioned embodiment, so please refer to the above-mentioned embodiment, and for the sake of brevity, will not be further described here.

[0066] 504, determining whether the maximum overcurrent value is less than a third threshold value.

[0067] 506, if the maximum overcurrent value is less than a third threshold, increase the total current limit value of the energy storage system.

[0068] The third threshold refers to a third current parameter preset in the energy storage system, and may be a preset value less than zero. If the maximum overcurrent value is less than the third threshold, increase the total current limit value of the energy storage system. The third threshold current parameter may include a fixed value, a modifiable value, a value determined by a table lookup method, or a value determined by a correlation function, and the embodiments of the present application are not limited thereto.

[0069] If it is determined that the maximum overcurrent value is less than the third threshold, the total current limit value of the energy storage system is increased. If the maximum overcurrent value is equal to or greater than the third threshold, the total current limit value of the energy storage system is not increased, and the current value of each battery cluster is continued to be monitored.

[0070] In an embodiment of the present application, the total current limit value of the energy storage system is increased based on the magnitude relationship between the maximum overcurrent value and the third threshold value, and when there is no overcurrent in the battery cluster of the branch circuit of the energy storage system and the maximum overcurrent value is less than the third threshold value, the total current limit value of the energy storage system may be increased so that the energy storage system has a large working current and maintains high power.

[0071] Optionally, in one embodiment of the present application, the total current limit value may be increased in a stepwise manner. Specifically, the total current limit value may be increased stepwise until the maximum overcurrent value is equal to or greater than the fourth threshold value. Increasing the total current limit value stepwise means gradually increasing the total current limit value at a predetermined speed. Referring to FIG. 6, FIG. 6 is a schematic flow chart of an overcurrent adjustment method for an energy storage system according to one embodiment of the present application. 601-604 in FIG. 6 are similar to 501-504 in the previous embodiment, so reference may be made to the previous embodiment, and will not be further described here for the sake of brevity.

[0072] 605, if the maximum overcurrent value is less than the third threshold, I u / sec Increases the total current limit.

[0073] I u is the rate at which the total current limit is stepped up. u The value of may be preset or adjusted in real time, and the embodiments of the present application are not limited thereto.

[0074] 606, determining whether the maximum overcurrent value is greater than or equal to a fourth threshold value.

[0075] In the process of gradually increasing the total current limit value, the maximum overcurrent value of the energy storage system needs to be monitored in real time, and a fourth threshold is set to determine whether the energy storage system needs to continue increasing the total current limit value. That is, every time the total current limit value is increased, the current value and overcurrent capability of each battery cluster need to be obtained again, and the overcurrent value and the corresponding maximum overcurrent value of each battery cluster need to be determined, that is, 601 to 603 need to be performed again. Then, it is determined whether the maximum overcurrent value is equal to or greater than the fourth threshold value.

[0076] 607, if the maximum overcurrent value is less than the fourth threshold, return to 605 and select I u / sec Increases the total current limit.

[0077] The fourth threshold refers to a fourth current parameter that is preset in the energy storage system and is greater than the third threshold, for example, the fourth threshold may be -2A, and the fourth threshold current parameter may include a fixed value, a modifiable value, a value determined by a table lookup method, or a value determined by a correlation function, and the embodiments of the present application are not limited thereto. If the maximum overcurrent value is greater than or equal to the fourth threshold, stop increasing the total current limit value of the energy storage system.

[0078] In the embodiment of the present application, a stepwise increase method is adopted to gradually increase the total current limit value of the energy storage system, thus avoiding the current of the energy storage system changing too quickly due to the total current limit value being increased too quickly, which may damage the performance of the battery cluster. As the total current limit value increases, the maximum overcurrent value calculated in real time also increases gradually, but by setting a fourth threshold value, the increase in the total current limit value can be stopped when the maximum overcurrent value is equal to or greater than the fourth threshold value, thus avoiding the total current limit value of the energy storage system being increased too much, which may cause an overcurrent.

[0079] The above describes the method for adjusting an overcurrent in an energy storage system according to an embodiment of the present application. The following describes an energy storage system according to an embodiment of the present application. Hereinafter, the above embodiments may be referred to for parts that are not described in detail.

[0080] FIG. 7 is a schematic diagram of an energy storage system according to one embodiment of the present application, in which the energy storage system may include multiple battery clusters 701, multiple current sensors 702, multiple sub-control units 703, and a main control unit 704.

[0081] A number of battery clusters 701 are connected in parallel.

[0082] The multiple current sensors 702 may be used to obtain a current value of each battery cluster among the multiple battery clusters 701, respectively.

[0083] The sub-control units 703 may be used to obtain a current value of each battery cluster of the battery clusters 701 from the current sensors 702 .

[0084] The main control unit 704 may be used to adjust a total current limit value of the energy storage system based on a maximum overcurrent value among the overcurrent values ​​of the multiple battery clusters 701. The overcurrent value of each battery cluster is determined based on the current value of each battery cluster and the overcurrent capability of each battery cluster. For example, the overcurrent value of each battery cluster may be a difference value obtained by subtracting the overcurrent capability of each battery cluster from the current value of each battery cluster.

[0085] In some embodiments of the present application, the main control unit 704 reduces the total current limit value when the maximum overcurrent value is greater than a first threshold, the first threshold being a preset value greater than zero. For example, the first threshold may be 2A.

[0086] In some embodiments of the present application, the main control unit 704 gradually reduces the total current limit value when the maximum overcurrent value is greater than a first threshold value until the maximum overcurrent value is equal to or less than a second threshold value, which is less than the first threshold value. For example, the second threshold value may be 0.

[0087] In some embodiments of the present application, the main control unit 704 increases the total current limit value if the maximum overcurrent value is less than a third threshold, where the third threshold is a preset value less than zero.

[0088] In some embodiments of the present application, the main control unit 704 increases the total current limit value stepwise when the maximum overcurrent value is less than the third threshold, until the maximum overcurrent value is equal to or greater than the fourth threshold, which is greater than the third threshold. For example, the fourth threshold may be -2A.

[0089] An embodiment of the present application further provides an overcurrent adjustment device for an energy storage system, the device including: a memory for storing a computer program; and a processor for calling the computer program to cause the device to realize the method of each of the embodiments of the present application described above.

[0090] An embodiment of the present application further provides a computer-readable storage medium for storing a computer program, which, when executed by a computing device, causes the computing device to implement the methods of each of the embodiments of the present application described above.

[0091] Although the present application has been described with reference to the preferred embodiments, various improvements may be made thereto and the elements therein may be replaced with equivalents without departing from the scope of the present application. In particular, as long as there is no structural contradiction, any of the technical features mentioned in each embodiment may be combined in any manner. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions included in the claims.

Claims

1. 1. A method for regulating an overcurrent in an energy storage system, the energy storage system including a plurality of battery clusters connected in parallel, obtaining a current value and an overcurrent capability of each battery cluster among the plurality of battery clusters; determining an overcurrent value for each battery cluster based on the current value and the overcurrent capability; determining a maximum overcurrent value among the overcurrent values ​​of the plurality of battery clusters; adjusting a total current limit value of the energy storage system based on the maximum overcurrent value; The method for adjusting an overcurrent in an energy storage system, wherein the overcurrent value of each battery cluster is a difference value obtained by subtracting the overcurrent capability of each battery cluster from the current value of each battery cluster.

2. adjusting a total current limit value of the energy storage system based on the maximum overcurrent value, 2. The method of claim 1, comprising: lowering the total current limit value if the maximum overcurrent value is greater than a first threshold, where the first threshold is a preset value greater than zero.

3. The reducing the total current limit value includes:

3. The method of claim 2, further comprising gradually decreasing the total current limit value until the maximum overcurrent value is equal to or less than a second threshold, wherein the second threshold is less than a preset value of the first threshold.

4. 4. The method of claim 3, wherein the second threshold is zero.

5. adjusting a total current limit value of the energy storage system based on the maximum overcurrent value, 5. The method of claim 1, further comprising increasing the total current limit value if the maximum overcurrent value is less than a third threshold, wherein the third threshold is a preset value less than zero.

6. Increasing the total current limit value includes:

6. The method of claim 5, comprising increasing the total current limit value in steps until the maximum overcurrent value is greater than or equal to a fourth threshold, wherein the fourth threshold is greater than the third threshold.

7. 7. The method of claim 6, wherein the fourth threshold is -2A.

8. 1. An energy storage system comprising: a plurality of battery clusters connected in parallel; a plurality of current sensors for acquiring current values ​​of each of the plurality of battery clusters; a plurality of sub-control units for acquiring a current value of each of the plurality of battery clusters from the plurality of current sensors; a main control unit for adjusting a total current limit value of the energy storage system based on a maximum overcurrent value among the overcurrent values ​​of the plurality of battery clusters, wherein the overcurrent value of each battery cluster is determined based on a current value of each battery cluster and an overcurrent capacity of each battery cluster, and the overcurrent value of each battery cluster is a difference value obtained by subtracting the overcurrent capacity of each battery cluster from the current value of each battery cluster.

9. 9. The energy storage system of claim 8, wherein the main control unit is adapted to reduce the total current limit value when the maximum overcurrent value is greater than a first threshold, where the first threshold is a preset value greater than zero.

10. 10. The energy storage system of claim 9, wherein the main control unit is used to gradually decrease the total current limit value until the maximum overcurrent value is equal to or less than a second threshold value, where the second threshold value is less than a preset value of the first threshold value.

11. 11. The energy storage system of claim 10, wherein the second threshold is zero.

12. 12. The energy storage system of claim 8, wherein the main control unit is adapted to increase the total current limit value when the maximum overcurrent value is less than a third threshold, where the third threshold is a preset value less than zero.

13. 13. The energy storage system of claim 12, wherein the main control unit is used to incrementally increase the total current limit value until the maximum overcurrent value is greater than or equal to a fourth threshold, where the fourth threshold is greater than the third threshold.

14. 14. The energy storage system of claim 13, wherein the fourth threshold is −2A.

15. An overcurrent adjustment device for an energy storage system, comprising: a memory for storing a computer program; and a processor for calling the computer program and causing the device to implement the method according to any one of claims 1 to 7.

16. A computer-readable storage medium having a computer program stored thereon, the computer program causing a computing device to implement a method according to any one of claims 1 to 7 when executed by the computing device.

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