Energy storage system and management method thereof

Abstract

The present application relates to an energy storage system and a method for managing such a system. The energy storage system includes a battery system, a battery management system, and an energy storage converter. The battery system includes multiple battery clusters. The battery management system includes multiple cluster-level battery management units. The multiple cluster-level battery management units are communicatively connected to each other, and each cluster-level battery management unit is connected to a battery cluster in a one-to-one correspondence. The energy storage converter is connected to the multiple battery clusters, and the energy storage converter is communicatively connected to at least one cluster-level battery management unit. The energy storage system provided by the present application can save hardware costs.

Description

Technical Field

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

[0002] With the rapid development of new energy technologies, energy storage systems have become one of the most important research directions.

[0003] Energy storage systems usually adopt a three-level management system, consisting of a battery management unit (BMU), a cluster-level battery management unit (SBMU), and a master battery management unit (MBMU).

[0004] However, the main function of the main battery management unit is currently only to forward the data collected by the cluster-level battery management units, and the three-level management system has the problem of wasting hardware costs. Summary of the Invention

[0005] Based on the above problems, the present application provides an energy storage system and a management method for the energy storage system, which can save hardware costs.

[0006] In a first aspect, the present application provides an energy storage system, which includes a battery system, a battery management system and an energy storage inverter. The battery system includes multiple battery clusters, the battery management system includes multiple cluster-level battery management units, the multiple cluster-level battery management units are communicatively connected to each other, each cluster-level battery management unit is connected to a battery cluster in a one-to-one correspondence, the energy storage inverter is connected to multiple battery clusters; and the energy storage inverter is communicatively connected to at least one cluster-level battery management unit.

[0007] In the technical solution of the embodiment of the present application, a cluster-level battery management unit among multiple cluster-level battery management units that is connected to the energy storage inverter is used as the host, and the cluster-level battery management unit serving as the host implements the control and management functions without the need to set up a main battery management unit. Therefore, the battery management architecture can be simplified and hardware costs can be saved.

[0008] In some embodiments, the cluster-level battery management unit is used to receive battery information sent by other cluster-level battery management units and control the operation of other cluster-level battery management units based on the battery information when it is in communication connection with the energy storage inverter, and / or receive converter information sent by the energy storage inverter and control the operation of the energy storage inverter based on the converter information.

[0009] In the technical solution of the embodiment of the present application, the cluster-level battery management unit can act as a host to implement control and management functions after being connected to the energy storage converter, without the need to set up a main battery management unit. Therefore, the battery management architecture can be simplified and hardware costs can be saved.

[0010] In some embodiments, the cluster-level battery management unit is configured to, upon receiving converter information, send a first control instruction to the energy storage converter based on the converter information. The first control instruction is configured to instruct the energy storage converter to control the charging and / or discharging of multiple battery clusters. In the technical solutions of the embodiments of the present application, the cluster-level battery management unit, acting as a host, implements the charging and discharging control function for the battery cluster.

[0011] In some embodiments, the cluster-level battery management unit is further configured to, after being communicatively connected to the energy storage converter, send a second control instruction to the energy storage converter based on a pre-acquired power regulation curve. The power regulation curve matches the peak-valley electricity price, and the second control instruction is configured to instruct the energy storage converter to implement a peak-shaving and valley-filling strategy. In the technical solutions of the embodiments of the present application, peak-shaving and valley-filling of electricity costs are achieved by the cluster-level battery management unit acting as the host.

[0012] In some embodiments, the cluster-level battery management unit is further configured to determine voltage extremes, current extremes, and temperature extremes of multiple battery clusters based on battery information. In the technical solution of the embodiment of the present application, battery status monitoring is implemented by the cluster-level battery management unit as a host.

[0013] In some embodiments, the cluster-level battery management unit is further configured to transmit battery information to the cluster-level battery management unit in communication with the energy storage inverter if no communication connection with the energy storage inverter is detected. In the technical solutions of the embodiments of the present application, multiple cluster-level battery management units cooperate with each other, eliminating the need for a master battery management unit to manage the energy storage system, thereby saving hardware costs.

[0014] In some embodiments, each battery cluster includes at least one battery cell, and the battery management system further includes multiple battery management units (BMUs). Each BMU is connected to a battery cell in a one-to-one correspondence, and each cluster-level BMU is connected to at least one BMU. The cluster-level BMU is configured to obtain battery information from the at least one BMU. The technical solution of the present embodiment utilizes cluster-level BMUs and BMUs to construct a two-level battery management architecture. This not only implements the functionality of a traditional three-level battery management architecture but also simplifies the battery management architecture.

[0015] In some embodiments, the cluster-level battery management unit is further used to store battery information. In the technical solution of the embodiment of the present application, the stored battery information facilitates subsequent statistics and aggregation by users.

[0016] In some embodiments, the multiple cluster-level battery management units are connected via a controller area network bus, and the cluster-level battery management units are connected to the energy storage converter via an Ethernet connection. In the technical solutions of the embodiments of the present application, communication between the battery management systems is achieved via the CAN bus and Ethernet, thereby enabling management of the energy storage system.

[0017] In a second aspect, the present application further provides a management method for an energy storage system, which is used for any cluster-level battery management unit in the energy storage system. The energy storage system is as in the first aspect, and the method includes:

[0018] When a communication connection is established with the energy storage converter in the energy storage system, converter information sent by the energy storage converter is received, and the operation of the energy storage converter is controlled according to the converter information.

[0019] In the technical solution of the embodiment of the present application, one of the multiple cluster-level battery management units is used as the host, and the cluster-level battery management unit serving as the host manages the energy storage inverter. Since there is no need to set up a main battery management unit, the battery management architecture can be simplified and hardware costs can be saved.

[0020] In some embodiments, controlling the operation of the energy storage converter based on converter information includes: sending a first control instruction to the energy storage converter based on the converter information, the first control instruction being used to instruct the energy storage converter to control the charging and / or discharging of multiple battery clusters in the energy storage system. In the technical solutions of the embodiments of the present application, the energy storage converter is controlled by a cluster-level battery management unit acting as a host, thereby enabling charging and discharging of the battery cluster.

[0021] In some embodiments, the above-mentioned control of the energy storage converter according to the converter information includes: sending a second control instruction to the energy storage converter according to the pre-acquired power regulation curve, the power regulation curve matches the peak-valley electricity price, and the second control instruction is used to instruct the energy storage converter to execute the peak shaving and valley filling strategy. In the technical solution of the embodiment of the present application,

[0022] In some embodiments, the method further includes receiving battery information sent by other cluster-level battery management units and controlling the operation of the other cluster-level battery management units based on the battery information. In the technical solution of the embodiment of the present application, one of the multiple cluster-level battery management units is used as a master, and the cluster-level battery management unit serving as the master manages the other cluster-level battery management units. Since a master battery management unit is no longer required, the battery management architecture can be simplified and hardware costs can be saved.

[0023] In some embodiments, the method further includes determining voltage extremes, current extremes, and temperature extremes for multiple battery clusters in the energy storage system based on the battery information. In the technical solution of the embodiments of the present application, battery status monitoring is implemented using a cluster-level battery management unit as a host. Since a master battery management unit is no longer required, the battery management architecture can be simplified and hardware costs can be saved.

[0024] In some embodiments, the method further includes: when multiple cluster-level battery management units are connected to the energy storage inverter, screening a target cluster-level battery management unit from the multiple cluster-level battery management units, so that the target cluster-level battery management unit performs the step of receiving inverter information sent by the energy storage inverter. In the technical solution of the embodiments of the present application, the multiple cluster-level battery management units can be used in turn, and when the current host fails, management will be taken over by a normal host, thereby ensuring management reliability.

[0025] In some embodiments, the method further includes: sending battery information to a cluster-level battery management unit in communication with the energy storage converter when no communication connection is established with the energy storage converter. In the technical solution of the embodiment of the present application, peak shaving and valley filling are achieved by the cluster-level battery management system as the host.

[0026] In some embodiments, the method further comprises: obtaining battery information from at least one battery management unit in the energy storage system. In the technical solution of the embodiment of the present application, battery status monitoring is implemented by a cluster-level battery management unit as a host.

[0027] In some embodiments, the method further includes: storing battery information. In the technical solution of the embodiment of the present application, the battery information provides a basis for the cluster-level battery management unit to manage the energy storage system, monitor battery status, perform information statistics, and handle faults. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the optional embodiments below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present application. The same reference numerals are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0029] Figure 1 It is a structural diagram of the energy storage system in traditional technology;

[0030] Figure 2 This is one of the structural diagrams of the energy storage system in one embodiment of the present application;

[0031] Figure 3 This is one of the structural diagrams of the energy storage system in one embodiment of the present application;

[0032] Figure 4 This is one of the step flow charts of the energy storage system management method in one embodiment of the present application;

[0033] Figure 5 This is the second step flow chart of the method for managing an energy storage system in one embodiment of the present application;

[0034] Description of reference numerals:

[0035] Battery system 10, battery management system 20, energy storage converter 30;

[0036] Battery cluster 101 , cluster-level battery management unit 201 , battery unit 102 , battery management unit 202 . DETAILED DESCRIPTION

[0037] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which this application belongs; the terms used herein are only for the purpose of describing 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-mentioned figure descriptions are intended to cover non-exclusive inclusions.

[0039] In the description of the embodiments of this application, the technical terms "first" and "second" are used only to distinguish different objects and should not be understood to indicate or imply relative importance or implicitly specify the quantity, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise clearly and specifically defined.

[0040] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0041] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0042] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two). Similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0043] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, technical terms such as "installed," "connected," "connected," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integration; mechanical connections or electrical connections; direct connections or indirect connections through an intermediate medium; internal connections between two components or interactions between two components. Those skilled in the art can understand the specific meanings of the above terms in the embodiments of the present application based on specific circumstances.

[0044] Currently, refer to Figure 1 Energy storage systems typically employ a three-tiered management system consisting of a battery management unit (BMU), a cluster-level battery management unit (SBMU), and a master battery management unit (MBMU). However, the MBMU's primary function is simply to forward data collected by the cluster-level SBMUs. Therefore, this three-tiered management system wastes hardware costs.

[0045] An embodiment of the present application discloses an energy storage system, which includes a battery system, a battery management system and an energy storage inverter. The battery management system includes a cluster-level battery management unit SBMU and a battery management unit BMU, but does not include a main battery management unit MBMU. Instead, the cluster-level battery management unit SBMU, which is communicatively connected to the energy storage inverter, implements the functions of the main battery management unit MBMU. In this way, the management system is simplified from the current three levels to the two levels in the embodiment of the present application, thereby saving hardware costs.

[0046] The energy storage system disclosed in the embodiments of the present application can be used in, but is not limited to, electrical devices such as vehicles, ships, or aircraft.

[0047] According to some embodiments of the present application, referring to Figure 2 , provides an energy storage system, which includes a battery system 10, a battery management system 20 and a power conversion system (PCS) 30. The battery system 10 includes multiple battery clusters 101, the battery management system 20 includes multiple cluster-level battery management units 201, the multiple cluster-level battery management units 201 are communicatively connected to each other, and each cluster-level battery management unit 201 is connected to a battery cluster 101 in a one-to-one correspondence. The power conversion system 30 is connected to multiple battery clusters 101, and the power conversion system is communicatively connected to at least one cluster-level battery management unit.

[0048] In this embodiment of the present application, the energy storage system includes a battery system 10, a battery management system 20, and an energy storage converter 30. The battery system 10 is composed of multiple battery clusters 101 connected in parallel, each of which includes at least one battery cell. The battery management system 20 includes multiple cluster-level battery management units 201, each connected to a battery cluster 101 to manage the batteries in the corresponding cluster. The energy storage converter 30 is connected to the multiple battery clusters 101 to control them. Figure 2 In the figure, straight lines are communication connections and dotted lines are electrical connections.

[0049] The energy storage converter is communicatively connected to at least one cluster-level battery management unit (BMU). One or more cluster-level BMUs 201 and 202 among the multiple cluster-level BMUs 201 establish a communication connection with the energy storage converter 30. The cluster-level BMU 201 that has established a communication connection with the energy storage converter 30 serves as the master among the multiple cluster-level BMUs 201. Other cluster-level BMUs 201 that have not established a communication connection with the energy storage converter 30 serve as slaves among the multiple cluster-level BMUs 201.

[0050] The cluster-level battery management unit 201 as a host can manage the energy storage converter and other cluster-level battery clusters. The embodiment of the present application does not limit the specific management method.

[0051] In the above embodiment, the energy storage system includes a battery system, a battery management system, and an energy storage inverter. The battery system includes multiple battery clusters. The battery management system includes multiple cluster-level battery management units. The multiple cluster-level battery management units are communicatively connected to each other. Each cluster-level battery management unit is connected to a battery cluster in a one-to-one correspondence. The energy storage inverter is connected to multiple battery clusters, and the energy storage inverter is connected to at least one cluster-level battery management unit. In the embodiment of the present application, one of the multiple cluster-level battery management units that is communicatively connected to the energy storage inverter serves as the host. The cluster-level battery management unit serving as the host implements the control and management functions without the need for a master battery management unit. Therefore, the battery management architecture can be simplified and hardware costs can be saved.

[0052] According to some embodiments of the present application, the cluster-level battery management unit 201 is used to receive battery information sent by other cluster-level battery management units 201 when in communication connection with the energy storage inverter 30, and control the operation of other cluster-level battery management units 201 according to the battery information, and / or receive converter information sent by the energy storage inverter 30, and control the operation of the energy storage inverter 30 according to the converter information.

[0053] The cluster-level battery management unit 201, acting as the master, performs the following functions: it receives battery information sent by other cluster-level battery management units 201 and controls the operation of other cluster-level battery management units 201 based on the battery information. Battery information may include the voltage, current, and temperature of individual batteries, as well as the voltage and current of the battery cluster. This embodiment of the application does not limit the battery information and can be configured based on actual circumstances.

[0054] For example, after receiving battery information, cluster-level battery management unit A1, acting as the host, determines based on the battery information that battery cluster B1 needs to reduce its output power. It then controls the operation of cluster-level battery management unit A2, connected to battery cluster B1, causing cluster-level battery management unit A2 to reduce the output power of battery cluster B1. Alternatively, after receiving battery information, cluster-level battery management unit A1, acting as the host, determines based on the battery information that battery cluster B2 has failed. It then controls the operation of cluster-level battery management unit A3, connected to battery cluster B2, causing cluster-level battery management unit A3 to implement appropriate protective measures, such as reducing the high voltage of battery cluster B2.

[0055] The cluster-level battery management system, acting as the host, can also perform the following functions: receiving converter information sent by the energy storage converter 30 and controlling the operation of the energy storage converter 30 based on the converter information. The converter information may include the operating power, operating status, and whether the energy storage converter is faulty. This embodiment of the application does not limit the converter information and can be configured based on actual circumstances.

[0056] For example, the energy storage converter 30 sends converter information to the cluster-level battery management unit A1 as the host. The cluster-level battery management unit A1 controls the operating power and operating status of the energy storage converter 30 according to the converter information, or controls the energy storage converter 30 to handle faults.

[0057] It should be noted that the control functions that can be realized by the cluster-level battery management unit as a host are not limited to the above description, and the functions of the main battery management unit MBMU and the energy management system EMS used in traditional technologies can also be integrated.

[0058] In some embodiments, identifications are set for the multiple cluster-level battery management units 201 , for example, the multiple cluster-level battery management units 201 are numbered to distinguish the cluster-level battery management units 201 so as to better control the cluster-level battery management units 201 .

[0059] In the above-described embodiment, the cluster-level battery management unit, while in communication with the energy storage inverter, receives battery information sent by other cluster-level battery management units and controls the operation of the other cluster-level battery management units based on the battery information, and / or receives converter information sent by the energy storage inverter and controls the operation of the energy storage inverter based on the converter information. In the embodiment of the present application, one of the multiple cluster-level battery management units serves as the master, and the cluster-level battery management unit serving as the master performs control and management functions, eliminating the need for a master battery management unit. This simplifies the battery management architecture and saves hardware costs.

[0060] According to some embodiments of the present application, the cluster-level battery management unit 201 is used to send a first control instruction to the energy storage inverter 30 according to the inverter information after receiving the inverter information, and the first control instruction is used to instruct the energy storage inverter 30 to control the charging and / or discharging of multiple battery clusters 101.

[0061] In an embodiment of the present application, one of the functions of the cluster-level battery management unit 201, acting as a host, is to control the charging and / or discharging of the battery cluster 101 through the energy storage inverter 30. For example, the cluster-level battery management unit A1 acts as the host, and the energy storage inverter 30 sends the charging power of battery cluster B1 to the cluster-level battery management unit A1. The cluster-level battery management unit A1 then sends a first control instruction to the energy storage inverter 30 based on the charging power of battery cluster B1. The energy storage inverter 30 receives the first control instruction and adjusts the charging power of battery cluster B1 based on the first control instruction. Alternatively, the energy storage inverter 30 sends the discharging power of battery cluster B2 to the cluster-level battery management unit A1. The cluster-level battery management unit A1 then sends a first control instruction to the energy storage inverter 30 based on the discharging power of battery cluster B2. The energy storage inverter 30 receives the first control instruction and adjusts the discharging power of battery cluster B2 based on the first control instruction.

[0062] In the above embodiment, after receiving the converter information, the cluster-level battery management unit sends a first control instruction to the energy storage converter based on the converter information, instructing the energy storage converter to control the charging and / or discharging of multiple battery clusters. In this embodiment, the cluster-level battery management unit acts as the host to achieve battery cluster charging and discharging control without requiring a master battery management unit. This simplifies the battery management architecture and reduces hardware costs.

[0063] According to some embodiments of the present application, the cluster-level battery management unit 201 is further used to send a second control instruction to the energy storage inverter 30 according to a pre-acquired power regulation curve after being communicatively connected with the energy storage inverter 30, and the second control instruction is used to instruct the energy storage inverter 30 to execute a peak shaving and valley filling strategy.

[0064] The power regulation curve matches the peak and valley electricity prices. That is, when the electricity price is high, the discharge power in the power regulation curve is higher and the charging power is lower. When the electricity price is low, the discharge power in the power regulation curve is lower and the charging power is higher. In practical applications, the peak and valley electricity prices and power regulation curves can be pre-stored in each cluster-level battery management unit 201. In this way, when any cluster-level battery management unit 201 acts as the master, it can implement corresponding control based on the power regulation curve.

[0065] In this embodiment of the present application, the cluster-level battery management unit 201, acting as a host, also has the function of implementing peak-shaving and valley-shaving of electricity costs through the energy storage converter 30. Specifically, the cluster-level battery management unit 201, acting as a host, sends a second control instruction to the energy storage converter 30 based on a pre-acquired power regulation curve. The energy storage converter 30 adjusts the battery charging power and / or discharging power according to the second control instruction, causing the battery cluster 101 to discharge when electricity prices are high and charge when prices are low. This reduces the electricity costs of the energy storage system and implements peak-shaving and valley-shaving of electricity costs.

[0066] In the above-described embodiment, after the cluster-level battery management unit is connected to the energy storage inverter, it sends a second control instruction to the energy storage inverter based on the pre-acquired power regulation curve, instructing the energy storage inverter to implement a peak-shaving and valley-filling strategy. In this embodiment, the cluster-level battery management unit, acting as the host, achieves peak-shaving and valley-filling of electricity costs. Since a master battery management unit is not required, the battery management architecture can be simplified, saving hardware costs.

[0067] According to some embodiments of the present application, the cluster-level battery management unit 201 is further configured to determine voltage extremes, current extremes, and temperature extremes of the plurality of battery clusters 101 based on the battery information.

[0068] In this embodiment of the present application, the cluster-level battery management unit 201, acting as the host, also has the function of monitoring battery status. Specifically, after acquiring battery information from other cluster-level battery management units 201, the cluster-level battery management unit 201, acting as the host, can calculate the maximum and minimum values of the battery voltage, the maximum and minimum values of the battery current, the maximum and minimum values of the battery temperature, as well as the maximum and minimum values of the cluster voltage, and the maximum and minimum values of the cluster current. In actual applications, the voltage extremes, current extremes, and temperature extremes are not limited to those described above.

[0069] After calculating various extreme values, the cluster-level battery management unit 201, acting as the host, can determine whether the battery cells and battery cluster 101 are operating within normal ranges based on pre-set thresholds. If the calculated extreme value exceeds the pre-set threshold, it indicates that an abnormality has occurred in the battery or battery cluster 101, and appropriate protective measures must be taken.

[0070] The protective measures may include reducing battery voltage, reducing battery current, reducing battery temperature, reducing battery cluster 101 voltage, reducing battery cluster 101 current, performing high voltage operation on battery cluster 101, etc. The present embodiment does not limit the protective measures and can be set according to actual conditions.

[0071] In the above-mentioned embodiment, the cluster-level battery management unit determines the voltage, current, and temperature extremes of multiple battery clusters based on battery information. In the present embodiment, the cluster-level battery management unit acts as the host to monitor battery status. This eliminates the need for a master battery management unit, simplifying the battery management architecture and saving hardware costs.

[0072] According to some embodiments of the present application, the cluster-level battery management unit 201 is further configured to send battery information to the cluster-level battery management unit 201 in communication connection with the energy storage converter 30 when no communication connection with the energy storage converter 30 is detected.

[0073] In the embodiment of the present application, if the cluster-level battery management unit 201 has not established a communication connection with the energy storage converter 30, it acts as a slave among the multiple cluster-level battery management units 201. The main function of the cluster-level battery management unit 201 as a slave is to collect battery information and upload the battery information to the cluster-level battery management unit 201 as a master, so that the cluster-level battery management unit 201 as a master can manage the energy storage system.

[0074] For example, the cluster-level battery management unit A1 detects a communication connection with the energy storage inverter 30, while the cluster-level battery management units A2, A3... do not detect a communication connection with the energy storage inverter 30. Then, the cluster-level battery management unit A1 acts as the host, and the cluster-level battery management units A2, A3... act as slaves. The cluster-level battery management units A2, A3... send all the collected battery information to the cluster-level battery management unit A1.

[0075] In the above embodiment, if the cluster-level battery management unit does not detect a communication connection with the energy storage inverter, it sends battery information to the cluster-level battery management unit that is in communication with the energy storage inverter. In the embodiment of the present application, the cluster-level battery management unit, acting as a slave, collects battery information so that the cluster-level battery management unit, acting as a master, can manage the energy storage system based on the battery information. Multiple cluster-level battery management units cooperate with each other, so that the energy storage system can be managed without the need for a master battery management unit, thereby saving hardware costs.

[0076] According to some embodiments of the present application, referring to Figure 3Each battery cluster 101 includes at least one battery cell 102. The battery management system 20 also includes multiple battery management units 202. Each battery management unit 202 is connected to a battery cell 102 in a one-to-one correspondence. Each cluster-level battery management unit 201 is connected to at least one battery management unit 202. The cluster-level battery management unit 201 is used to obtain battery information from at least one battery management unit 202.

[0077] In the embodiment of the present application, each battery cluster 101 can be composed of multiple battery cells 102 connected in series. Each battery cell 102 can be a single battery cell or a battery box, which is not limited in the embodiment of the present application. The battery management system 20 also includes multiple battery management units 202, each of which is connected to a corresponding battery cell 102, and multiple battery management units 202 are connected to the cluster-level battery management unit 201 of the corresponding cluster. Figure 3 In the figure, straight lines are communication connections and dotted lines are electrical connections.

[0078] In actual applications, each battery management unit 202 collects battery information from the corresponding battery unit 102, such as the battery voltage, battery current, and battery temperature of the corresponding battery unit 102. Each battery unit 202 then uploads the received battery information to the cluster-level battery management unit 201 of the corresponding cluster. The cluster-level battery management unit 201 receives the battery information uploaded by at least one battery unit 202.

[0079] It should be noted that each cluster-level BMU 201, whether acting as a master or a slave, obtains battery information uploaded by the BMU 202 in the corresponding cluster. Furthermore, the master cluster-level BMU 201 also obtains battery information uploaded by the slave cluster-level BMU 201.

[0080] In some embodiments, the cluster-level battery management unit 201 is further configured to store battery information.

[0081] After acquiring battery information, each cluster-level battery management unit 201 can store it. The master cluster-level battery management unit 201 can also store battery information uploaded by slave cluster-level battery management units 201. Subsequent users can perform relevant statistics and summaries based on the stored battery information. Furthermore, the battery information can include fault information, abnormality information, and other information, which users can then review for troubleshooting.

[0082] In the above embodiment, each battery cluster includes at least one battery cell, and the battery management system also includes multiple battery management units. Each battery management unit is connected to a battery cell in a one-to-one correspondence, and each cluster-level battery management unit is connected to at least one battery management unit. The cluster-level battery management unit obtains battery information from the at least one battery management unit. The present embodiment of the present invention constructs a two-level battery management architecture by using cluster-level battery management units and battery management units. This not only implements the functions of the three-level battery management architecture used in traditional technologies, but also simplifies the battery management architecture.

[0083] According to some embodiments of the present application, the connection between the multiple cluster-level battery management units 201 is a controller area network (CAN) bus connection, and the connection between the cluster-level battery management unit 201 and the energy storage converter 30 is an Ethernet connection.

[0084] In an embodiment of the present application, multiple cluster-level battery management units 201 can be connected via a CAN bus. In this way, the cluster-level battery management unit 201 serving as a slave can upload battery information to the cluster-level battery management unit 201 serving as a host via the CAN bus; and the cluster-level battery management unit 201 serving as the host can also send control instructions to the cluster-level battery management unit 201 serving as a slave via the CAN bus, thereby controlling the cluster-level battery management unit 201 serving as a slave.

[0085] Each cluster-level BMU 201 can be provided with an Ethernet interface. After the user connects the cable connected to the energy storage converter 30 to the Ethernet interface of one cluster-level BMU 201, the cluster-level BMU 201 can act as a master, and the other cluster-level BMUs 201 can act as slaves.

[0086] In the above embodiment, multiple cluster-level battery management units are connected via a CAN bus, and the cluster-level battery management unit serving as the host is connected to the energy storage converter via Ethernet. The embodiment of the present application enables communication between battery management systems via the CAN bus and Ethernet, thereby achieving management of the energy storage system.

[0087] According to some embodiments of the present application, referring to Figure 4 , provides a management method for an energy storage system, which is applied to any cluster-level battery management unit in the energy storage system. The energy storage system is as described in the above embodiment. The embodiment of the present application may include the following steps:

[0088] Step 401, receiving converter information sent by the energy storage converter when a communication connection is established with the energy storage converter;

[0089] Step 402: Control the energy storage converter to operate according to the converter information.

[0090] If a cluster-level battery management unit (BMU) establishes a communication connection with an energy storage converter, it acts as the master for multiple cluster-level BMUs. As the master, the BMU receives converter information from the energy storage converter and controls the converter's operation based on this information.

[0091] For example, the cluster-level battery management unit A1 as a host can control the operating power and operating status of the energy storage converter, or control the energy storage converter to handle faults, etc. The embodiment of the present disclosure does not limit how to control the energy storage converter, and can be set according to actual conditions.

[0092] In the above-described embodiment, the cluster-level battery management unit in the energy storage system, while establishing a communication connection with the energy storage inverter in the energy storage system, receives converter information sent by the energy storage inverter and controls the operation of the energy storage inverter based on the converter information. In the embodiment of the present application, one of the multiple cluster-level battery management units serves as the master, and the cluster-level battery management unit serving as the master manages the energy storage inverter. Since a master battery management unit is no longer required, the battery management architecture can be simplified and hardware costs can be saved.

[0093] According to some embodiments of the present application, the above-mentioned process of controlling the operation of the energy storage converter according to the converter information may include: sending a first control instruction to the energy storage converter according to the converter information, the first control instruction being used to instruct the energy storage converter to control the charging and / or discharging of multiple battery clusters in the energy storage system.

[0094] In an embodiment of the present application, after receiving converter information from an energy storage converter, a cluster-level battery management unit (BMU) serving as a host determines, based on the converter information, to send a first control instruction to the energy storage converter. The energy storage converter receives the first control instruction and controls the charging of multiple battery clusters according to the first control instruction; or controls the discharging of multiple battery clusters according to the first control instruction; or controls the charging of some battery clusters while discharging other battery clusters.

[0095] In the above embodiment, the cluster-level battery management unit, acting as the host, sends a first control instruction to the energy storage inverter based on the inverter information, instructing the energy storage inverter to control the charging and / or discharging of multiple battery clusters in the energy storage system. In the present embodiment, the cluster-level battery management unit, acting as the host, enables charging and discharging of the battery cluster. This eliminates the need for a master battery management unit, thus simplifying the battery management architecture and reducing hardware costs.

[0096] According to some embodiments of the present application, the above-mentioned process of controlling the operation of the energy storage converter based on converter information may include: sending a second control instruction to the energy storage converter based on a pre-acquired power regulation curve, the power regulation curve matches the peak-valley electricity price, and the second control instruction is used to instruct the energy storage converter to execute a peak shaving and valley filling strategy.

[0097] In an embodiment of the present application, the cluster-level battery management unit serving as the host can obtain peak and valley electricity prices in advance and then determine a power regulation curve based on the peak and valley electricity prices; it can also directly obtain a power regulation curve formulated by the user based on the peak and valley electricity prices.

[0098] The cluster-level battery management unit, acting as the host, then sends a second control instruction to the energy storage converter based on the power regulation curve. Upon receiving the second control instruction, the energy storage converter increases discharge power and decreases charging power when electricity prices are high, and decreases discharge power and increases charging power when electricity prices are low. This allows the energy storage system to primarily discharge when electricity prices are high and primarily charge when prices are low, thereby shaving peak loads and shifting valleys, saving electricity costs.

[0099] In the above embodiment, the cluster-level battery management unit, acting as the host, sends a second control instruction to the energy storage converter based on the pre-acquired power regulation curve, instructing the energy storage converter to implement a peak-shaving and valley-filling strategy. In the present embodiment, peak-shaving and valley-filling are achieved by using the cluster-level battery management system as the host. Since a master battery management unit is no longer required, the battery management architecture can be simplified and hardware costs can be saved.

[0100] According to some embodiments of the present application, the method may further include: receiving battery information sent by other cluster-level battery management units, and controlling the operation of the other cluster-level battery management units according to the battery information.

[0101] In an embodiment of the present application, the cluster-level battery management unit serving as the host can also receive battery information sent by other cluster-level battery management units, determine the working mode of other cluster-level battery management units based on the battery information, and control the operation of other cluster-level battery management units based on the determined working mode.

[0102] For example, cluster-level battery management unit A1, acting as a host, can control cluster-level battery management units A2 and A3 to adjust the output power of the battery cluster, monitor the battery cluster, and implement protection measures. The disclosed embodiments do not limit how to control other cluster-level battery management units, and can be configured based on actual conditions.

[0103] In the above embodiment, battery information sent by other cluster-level battery management units is received and the operation of the other cluster-level battery management units is controlled based on the battery information. In the embodiment of the present application, one of the multiple cluster-level battery management units is used as the master, and the master cluster-level battery management unit manages the other cluster-level battery management units. Since a master battery management unit is no longer required, the battery management architecture can be simplified and hardware costs can be saved.

[0104] According to some embodiments of the present application, the method may further include: determining voltage extremes, current extremes, and temperature extremes of multiple battery clusters in the energy storage system according to the battery information.

[0105] In the embodiment of the present application, a cluster-level battery management unit, acting as a host, obtains battery information for multiple battery clusters. Based on the battery information for the multiple battery clusters, the maximum and minimum battery voltages, battery currents, and battery temperatures of multiple battery cells can be calculated. The maximum and minimum cluster voltages and cluster currents of multiple battery clusters can also be calculated. The embodiment of the present application does not limit the calculation of extreme values and can be configured based on actual conditions.

[0106] In the above embodiment, the cluster-level battery management unit, acting as the host, determines the voltage, current, and temperature extremes of multiple battery clusters in the energy storage system based on battery information. In the present embodiment, battery status monitoring is achieved by using the cluster-level battery management unit as the host. This eliminates the need for a master battery management unit, simplifying the battery management architecture and saving hardware costs.

[0107] According to some embodiments of the present application, the method may further include: when multiple cluster-level battery management units are connected to the energy storage converter, screening out a target cluster-level battery management unit from the multiple cluster-level battery management units so that the target cluster-level battery management unit executes the step of receiving converter information sent by the energy storage converter.

[0108] In practical applications, the energy storage converter can be connected to multiple cluster-level battery management units. A target cluster-level battery management unit can be screened out from the multiple cluster-level battery management units connected to the energy storage converter according to preset rules, and the target battery management unit executes steps 401 and 402.

[0109] Among them, the preset rules can be based on the connection time, the serial number of the cluster-level battery management, and the priority of the cluster-level battery management unit. The embodiment of the present application does not limit the preset rules.

[0110] For example, each cluster-level BMU determines the time to establish a communication connection with the energy storage inverter and selects the cluster-level BMU with the earliest connection time as the master. Alternatively, the cluster-level BMU with the highest sequence number among multiple cluster-level BMUs is selected as the master. Alternatively, the cluster-level BMU with the highest priority among multiple cluster-level BMUs can be selected as the master.

[0111] In the above embodiment, when multiple cluster-level battery management units are connected to the energy storage inverter, a target cluster-level battery management unit is selected from the multiple cluster-level battery management units so that the target cluster-level battery management unit performs the step of receiving the inverter information sent by the energy storage inverter. In the technical solution of the embodiment of the present application, multiple cluster-level battery management units can be used in turn, and when the current host fails, management is taken over by a normal host, ensuring management reliability.

[0112] According to some embodiments of the present application, referring to Figure 5 , the embodiment of the present application may further include the following steps:

[0113] Step 501 : Detect whether a communication connection is established with an energy storage converter in an energy storage system.

[0114] The cluster-level battery management unit detects whether a communication connection has been established with the energy storage converter in the energy storage system. Specifically, this can be done through software to detect whether a connection signal has been received from the energy storage connector, or through hardware to detect whether a cable is connected to the cluster-level battery management unit's Ethernet interface. It should be noted that the detection method is not limited to the one described above and can be configured based on actual circumstances.

[0115] Step 502 : When no communication connection is established with the energy storage converter, the battery information is sent to a cluster-level battery management unit in communication connection with the energy storage converter.

[0116] If a cluster-level BMU detects that it has no communication connection with the energy storage converter, it will act as a slave among multiple cluster-level BMUs. The slave cluster-level BMU can send battery information to the master cluster-level BMU via the CAN bus, allowing the master cluster-level BMU to manage the energy storage system based on the battery information.

[0117] In the above embodiment, when no communication connection is established with the energy storage converter, battery information is sent to the cluster-level battery management unit in communication with the energy storage converter. In the present embodiment, the cluster-level battery management unit, acting as a slave, uploads battery information, which can be used by the cluster-level battery management unit, acting as a master, to manage the energy storage system based on the battery information.

[0118] According to some embodiments of the present application, the method may further include: acquiring battery information from at least one battery management unit in the energy storage system.

[0119] The energy storage system may further include multiple battery management units, one battery management unit is connected to one battery cell, and multiple battery cells are connected to cluster-level battery management units of corresponding clusters.

[0120] Each battery management unit obtains battery information of the corresponding connected battery unit respectively; then, each battery management unit sends the obtained battery information to the cluster-level battery management unit of the corresponding cluster, so that each cluster-level battery management unit can obtain the battery information.

[0121] According to some embodiments of the present application, the method may further include: storing battery information.

[0122] After acquiring battery information, each cluster-level BMU can store it. The master cluster-level BMU can also store battery information uploaded from other cluster-level BMUs. Storing battery information facilitates subsequent statistics, aggregation, and review.

[0123] In the above embodiment, the cluster-level battery management unit obtains battery information from at least one battery management unit in the energy storage system and stores the battery information. This battery information provides a basis for the cluster-level battery management unit to manage the energy storage system, monitor battery status, perform information statistics, and handle faults.

[0124] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0125] The embodiments described above only express several implementation methods of the present application, which are convenient for understanding the technical solutions of the present application in a specific and detailed manner, but they cannot be understood as limiting the scope of protection of the invention patent. It should be pointed out that for ordinary technicians in this field, without departing from the concept of the present application, several variations and improvements can be made, which all fall within the scope of protection of the present application. It should be understood that the technical solutions obtained by those skilled in the art through logical analysis, reasoning or limited experiments on the basis of the technical solutions provided in the present application are all within the scope of protection of the attached claims described in the present application. Therefore, the scope of protection of the patent of this application shall be based on the content of the attached claims, and the description and drawings can be used to interpret the content of the claims.

Claims

1. An energy storage system, characterized in that: The energy storage system includes a battery system, a battery management system, and an energy storage converter. The battery system includes multiple battery clusters. The battery management system includes multiple cluster-level battery management units. The multiple cluster-level battery management units are communicatively connected to each other, and each cluster-level battery management unit is connected to the battery cluster in a one-to-one correspondence. The energy storage converter is connected to the multiple battery clusters, and the energy storage converter is communicatively connected to at least one of the cluster-level battery management units. The cluster-level battery management unit is configured to, when in communication with the energy storage converter, receive battery information sent by other cluster-level battery management units and control the operation of the other cluster-level battery management units according to the battery information, and / or receive converter information sent by the energy storage converter and control the operation of the energy storage converter according to the converter information; The cluster-level battery management unit is further configured to send the battery information to the cluster-level battery management unit in communication connection with the energy storage converter when no communication connection with the energy storage converter is detected.

2. The energy storage system according to claim 1, characterized in that The cluster-level battery management unit is configured to send a first control instruction to the energy storage inverter according to the inverter information after receiving the inverter information, wherein the first control instruction is configured to instruct the energy storage inverter to control the charging and / or discharging of the plurality of battery clusters.

3. The energy storage system according to claim 1, characterized in that The cluster-level battery management unit is further used to send a second control instruction to the energy storage inverter according to a pre-acquired power regulation curve after being communicatively connected with the energy storage inverter, wherein the power regulation curve matches the peak-valley electricity price, and the second control instruction is used to instruct the energy storage inverter to execute a peak shaving and valley filling strategy.

4. The energy storage system according to claim 1, characterized in that The cluster-level battery management unit is further configured to determine voltage extremes, current extremes, and temperature extremes of the plurality of battery clusters based on the battery information.

5. The energy storage system according to claim 1, characterized in that: Each of the battery clusters includes at least one battery cell, and the battery management system further includes a plurality of battery management units, each of the battery management units is connected to the battery cells in a one-to-one correspondence, and each of the cluster-level battery management units is connected to at least one of the battery management units; The cluster-level battery management unit is configured to obtain the battery information from at least one of the battery management units.

6. The energy storage system according to claim 1, characterized in that The cluster-level battery management unit is further configured to store the battery information.

7. The energy storage system according to claim 6, characterized in that: The plurality of cluster-level battery management units are connected in a controller area network bus manner, and the cluster-level battery management unit is connected to the energy storage converter in an Ethernet manner.

8. A method for managing an energy storage system, characterized in that: Applied to the energy storage system according to any one of claims 1 to 7, the method comprises: When a communication connection is established with an energy storage converter in the energy storage system, receiving converter information sent by the energy storage converter; The energy storage converter is controlled to operate according to the converter information.

9. The energy storage system management method according to claim 8, characterized in that: The step of controlling the energy storage converter to operate according to the converter information includes: A first control instruction is sent to the energy storage converter according to the converter information, where the first control instruction is used to instruct the energy storage converter to control charging and / or discharging of multiple battery clusters in the energy storage system.

10. The energy storage system management method according to claim 8, characterized in that: The step of controlling the energy storage converter to operate according to the converter information includes: A second control instruction is sent to the energy storage converter according to a pre-acquired power regulation curve, wherein the power regulation curve matches the peak-valley electricity price, and the second control instruction is used to instruct the energy storage converter to execute a peak shaving and valley filling strategy.

11. The energy storage system management method according to claim 8, characterized in that: The method further comprises: Receive battery information sent by other cluster-level battery management units, and control the operation of other cluster-level battery management units according to the battery information.

12. The energy storage system management method according to claim 8, characterized in that: The method further comprises: The voltage extremes, current extremes, and temperature extremes of the plurality of battery clusters in the energy storage system are determined according to the battery information.

13. The energy storage system management method according to claim 8, characterized in that: The method further comprises: When multiple cluster-level battery management units are connected to the energy storage converter, a target cluster-level battery management unit is selected from the multiple cluster-level battery management units so that the target cluster-level battery management unit performs the step of receiving converter information sent by the energy storage converter.

14. The energy storage system management method according to any one of claims 8 to 13, characterized in that: The method further comprises: In the case where a communication connection is not established with the energy storage converter, battery information is sent to a cluster-level battery management unit that is in communication connection with the energy storage converter.

15. The energy storage system management method according to claim 14, characterized in that: The method further comprises: The battery information is obtained from at least one battery management unit in the energy storage system.

16. The energy storage system management method according to claim 14, characterized in that: The method further comprises: The battery information is stored.

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