Equalization system and equalization device thereof

Abstract

The invention discloses an equalization system and equalization equipment thereof. A battery equalization master control module in the equipment obtains battery voltage in an energy storage system and determines target equalization voltage according to the battery voltage. The battery equalization control units are in one-to-one correspondence and connection with the battery plug-in boxes of the energy storage system, are also connected with the battery equalization master control module, and collect real-time voltages of the corresponding battery plug-in boxes; the DC-AC converters are connected with the battery equalization control units in a one-to-one correspondence manner and are also connected with the corresponding battery subracks, and the AC ends of the DC-AC converters are connected with an AC power supply; the battery equalization master control module obtains an equalization strategy of each battery plug-in box according to the target equalization voltage and each real-time voltage, equalizes each battery plug-in box, realizes the equalization operation of each battery plug-in box in the energy storage system, cooperates with each battery equalization control unit, automatically and accurately equalizes the batteries in the battery plug-in boxes, and improves the battery equalization efficiency. The equalization reliability is improved and the maintenance difficulty is reduced; synchronous equalization is carried out on a plurality of battery subracks, and equalization efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of energy storage technology, and in particular to a balancing system and its balancing equipment. Background Technology

[0002] As market electricity demand grows, energy storage systems are storing larger amounts of electricity and containing more and more battery modules, increasing the likelihood of inconsistencies among these modules. Furthermore, these inconsistencies tend to widen over time.

[0003] To mitigate inconsistencies between battery modules, balancing equipment is often needed to balance the battery modules in the later stages of an energy storage system's operation. Currently, the commonly used balancing method involves balancing the individual battery modules based on balancing parameters set by technicians.

[0004] However, this type of balancing equipment requires highly experienced technicians. If the technicians set the parameters improperly or incorrectly, the balancing effect will be unsatisfactory, and the maintenance efficiency of the energy storage system will also be affected. Summary of the Invention

[0005] This invention provides an equalization system and equalization device to optimize the equalization effect and reduce the reliance on technical personnel.

[0006] According to one aspect of the present invention, a balancing device is provided for balancing the battery voltage of an energy storage system, the balancing device comprising: The battery balancing control module is capable of acquiring the battery voltage V of all batteries in the energy storage system. cell And according to all the battery voltages V cell Obtain the target equalization voltage V tgt ; Multiple battery balancing control units are provided, each corresponding to a battery compartment in the energy storage system and capable of connection. Each battery balancing control unit is communicatively connected to the overall battery balancing control module and can collect the real-time voltage V of its corresponding battery compartment. rt ; Multiple DC-AC converters correspond one-to-one with multiple battery equalization control units, and the DC-AC converters are communicatively connected to the corresponding battery equalization control units and can be connected to the corresponding battery boxes. The AC terminals of the DC-AC converters can be connected to AC power sources. The battery equalization overall control module, based on the target equalization voltage V, tgt With each of the aforementioned real-time voltages V rt Obtain the balancing strategy corresponding to each battery box to perform voltage balancing for each battery box respectively.

[0007] Optionally, the battery balancing control module can also be connected to the battery management system of the energy storage system, and the battery balancing control module is configured to obtain the operating condition information of the energy storage system through the battery management system.

[0008] Optionally, the operating condition information of the energy storage system includes the battery voltage V of all batteries in the energy storage system. cell Rated capacity C cell and for acquiring the battery voltage V cell The type of acquisition harness.

[0009] Optionally, each of the battery balancing control units is configured with a unique device address, and the battery balancing master control module determines the real-time voltage V of the corresponding battery compartment based on the device address of the battery balancing control unit. rt And generate a balancing strategy corresponding to the battery box.

[0010] Optionally, the equalization strategy includes a target equalization voltage V. tgt The system includes equalizing current magnitude and equalizing operating modes, wherein the equalizing operating modes include constant voltage or constant current charging mode and constant voltage or constant current discharging mode.

[0011] Optionally, the battery balancing overall control module includes: The processing unit is capable of connecting to the battery management system of the energy storage system; the processing unit calculates the battery voltage V based on all the battery voltages V. cell Calculate the average voltage V of all batteries in the energy storage system. avg Maximum voltage V max and minimum voltage V min ; and according to the average voltage V avg The maximum voltage V max and the minimum voltage V min Obtain the target equalization voltage V tgt ;and A storage unit, connected to the processing unit, is used to store all of the battery voltages V. cell The average voltage V avg The maximum voltage V max and the minimum voltage V min .

[0012] Optionally, each of the battery balancing control units can be connected to the battery compartment via a controllable switch, and the battery balancing control unit includes: The voltage acquisition module can be connected to the battery box to acquire the real-time voltage V corresponding to the battery box. rt ;and The detection module is connected to the controllable switch and the corresponding DC-AC converter, respectively, and is used to detect the real-time status of the controllable switch and the real-time status of the DC-AC converter.

[0013] Optionally, the real-time status of the controllable switch includes the on / off status and fault condition of the controllable switch, and the real-time status of the DC-AC converter includes the operating mode of the DC-AC converter, the voltage level of the external power supply, and fault condition; the operating mode includes DC to AC and AC to DC.

[0014] Optionally, the battery balancing control module and the battery management system, the battery balancing control module and each of the battery balancing control units, and the battery balancing control units and the DC-AC converter are all connected via a controller area network.

[0015] According to another aspect of the present invention, an equalization system is provided, the equalization system including the equalization device described in the first aspect and an energy storage system, wherein the battery equalization master control module of the equalization device is connected to the battery management system of the energy storage system, and a plurality of DC-AC converters of the equalization device are respectively connected to the battery compartments of the energy storage system.

[0016] In the balancing system and balancing equipment of this application, the battery balancing master control module acquires the battery voltage in the energy storage system and obtains the target balancing voltage based on the battery voltage. The battery balancing control unit corresponds to and is connected to each battery compartment in the energy storage system, and is also connected to the battery balancing master control module, acquiring the real-time voltage of the corresponding battery compartment. The DC-AC converter corresponds to and is connected to each battery balancing control unit, and is also connected to the corresponding battery compartment; the AC terminal of the DC-AC converter is connected to an AC power source. The battery balancing master control module obtains the balancing strategy for each battery compartment based on the target balancing voltage and each real-time voltage, and performs balancing on each battery compartment, realizing the balancing operation of each battery compartment in the energy storage system. The battery balancing master control module, in conjunction with each battery balancing control unit, performs balancing control, which on the one hand can automatically and accurately balance the batteries in the battery compartments, improving balancing reliability and reducing system maintenance difficulty; on the other hand, it can simultaneously perform synchronous balancing on multiple battery compartments, improving balancing efficiency.

[0017] It should be understood that the description in this section is not intended to identify key or essential features of the embodiments of the present invention, nor is it intended to limit the scope of the invention. Other features of the invention will become readily apparent from the following description. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a circuit diagram of an equalization device proposed in an embodiment of the present invention; Figure 2 A circuit diagram of another equalization device and its corresponding energy storage system provided in an embodiment of the present invention; Figure 3 A circuit diagram of another equalization device provided in an embodiment of the present invention; Figure 4 A circuit diagram of a single equalization circuit in another equalization device provided in an embodiment of the present invention; Figure 5 A circuit diagram of a single equalization circuit in another equalization device provided in an embodiment of the present invention; Figure 6 A circuit diagram of a single equalization circuit in another equalization device provided in an embodiment of the present invention; Figure 7 This is a schematic diagram illustrating the connection relationship between an equalization device and its corresponding battery management system in an energy storage system, as provided in an embodiment of the present invention. Detailed Implementation

[0020] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0021] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0022] To address the problems mentioned in the background art, embodiments of the present invention provide a balancing device corresponding to an energy storage system, used to balance multiple battery boxes in the energy storage system. The battery box is a box-shaped battery assembly containing multiple batteries (also referred to as battery modules). The battery is the smallest unit to be balanced in the energy storage system and may include cell strings or individual cells. For example, if the battery is a cell string, then the number and model of individual cells included in each battery in the battery box are equal. Figure 1 This is a circuit diagram of an equalization device proposed in an embodiment of the present invention, with reference to... Figure 1 The equalization device 500 includes a battery equalization master control module 501, and battery equalization control units 102 and DC-AC converters 103 corresponding to the battery cells in the energy storage system. The battery equalization control units 102 and DC-AC converters 103 corresponding to the same battery cell can belong to the same equalization circuit 100. The battery equalization master control module 501 can acquire the battery voltage of all batteries in the energy storage system and obtain the target equalization voltage based on the total battery voltage. The battery balancing control unit 102 corresponds one-to-one with the battery boxes of the energy storage system and can be connected; the battery balancing control unit 102 is communicatively connected to the battery balancing master control module 501 and can collect the real-time voltage of the corresponding battery box; the DC-AC converter 103 corresponds one-to-one with multiple battery balancing control units 102, and the DC-AC converter 103 is communicatively connected to the corresponding battery balancing control unit 102 and can be communicatively connected to the corresponding battery box, and the AC terminal of the DC-AC converter 103 can be connected to an AC power source; wherein, the battery balancing master control module 501 obtains the balancing strategy corresponding to each battery box according to the target balancing voltage and each real-time voltage, so as to perform voltage balancing on each battery box respectively.

[0023] Specifically, the DC-AC converter 103 refers to the power electronic functional component in the equalization circuit 100 that enables bidirectional conversion between DC and AC power. The DC-AC converter 103 can both invert the DC power supplied by the battery compartment into AC power to discharge any battery in the battery compartment, and rectify the AC power supplied by the AC power source into DC power to charge each battery in the battery compartment. For example, the DC-AC converter 103 can utilize multiple controllable switching devices to form a full-bridge structure, and then achieve bidirectional flow and conversion between DC and AC power through pulse width modulation control of the controllable switching devices. The DC terminal of the DC-AC converter 103 can include multiple DC interfaces, which can be connected to corresponding batteries in the battery compartment; the AC terminal of the DC-AC converter 103 can be connected to at least one of the AC power sources such as the power grid and a generator set, thereby enabling the throughput of AC power. For example, when there are batteries in the battery compartment that need to be charged and balanced, the DC-AC converter 103 can convert the AC power connected to the AC terminal into DC power and charge and balance the corresponding battery module in the corresponding battery compartment; conversely, when there are batteries in the battery compartment that need to be discharged and balanced, the DC-AC converter 103 can convert the DC power connected to the DC terminal into AC power and send it to the AC power source from the AC terminal, for example, the AC power can be sent to the power grid.

[0024] The battery balancing control unit 102 is the control center of the entire balancing circuit 100. For example, the battery balancing control unit 102 may include a microcontroller, control chip, or integrated circuit with data acquisition, data analysis, communication, and control functions. The battery balancing control unit 102 can connect to each DC balancing line of the battery compartment to control the on / off state of the balancing lines. The balancing line refers to the connection line between the DC side of the DC-AC converter 103 and the corresponding battery in the battery compartment. For example, a controllable switch may be installed on the balancing line, and the on / off state of the controllable switch can be controlled by the battery balancing control unit 102.

[0025] The battery balancing control unit 102 can also connect to the corresponding battery box and sample the real-time voltage of the battery box, wherein the real-time voltage of the battery box can include the voltage of each battery in the battery box. For example, the balancing circuit 100 can also include a balancing connector 101 for connecting the battery box corresponding to the balancing circuit 100. The balancing connector 101 includes multiple balancing interfaces k, each balancing interface k corresponding to a balancing line, enabling synchronous balancing of multiple batteries in the battery box. The number of balancing interfaces k in the balancing connector 101 can be equal to the number of batteries in its corresponding battery box plus one. One additional balancing interface k can serve as a negative terminal interface, connected to the negative terminal of each battery, while the other balancing interfaces k are connected one-to-one to the negative terminals of the multiple batteries in the battery box. For example, the balancing connector 101 can be an integrated connector with multiple pluggable power interfaces. The battery balancing control unit 102 can include a voltage sampling connector, which includes sampling interfaces corresponding one-to-one with the balancing interfaces k, and the sampling interfaces are connected to their corresponding balancing interfaces k.

[0026] The battery equalization control unit 102 is also communicatively connected to the DC-AC converter 103 to detect and control the operating status of the DC-AC converter 103. For example, the battery equalization control unit 102 can communicate with the DC-AC converter 103 via a controller area network (also known as a CAN bus) and send control signals to it to control the on / off of electrical signals between the DC-AC converter 103 and each equalization line, as well as the direction of electrical signal transmission to each equalization line.

[0027] The battery balancing master control module 501 is the central control unit of the entire balancing device 500. It can acquire the battery voltage of all batteries in the energy storage system and determine the target balancing voltage accordingly. For example, each battery compartment can have its own target balancing voltage. The battery voltage is the voltage across the battery terminals. The battery balancing master control module 501 can obtain the battery voltage by communicating with the battery management system of the energy storage system and / or each battery balancing control unit 102. The battery balancing master control module 501 is also the upper-level controller of the battery balancing control unit 102 in each balancing circuit 100, and is communicatively connected to the battery balancing control unit 102 in each balancing circuit 100. On one hand, the battery balancing control module 501 can issue control commands to the battery balancing control unit 102 to control the working process of each balancing circuit 100. For example, the battery balancing control module 501 may include a microcontroller, control chip, or integrated circuit with data acquisition, data analysis, communication, and control functions. On the other hand, the battery balancing control module 501 can obtain the operating parameters of the corresponding balancing circuit 100 from the battery balancing control unit 102. For example, the operating parameters of the balancing circuit 100 may include the working status of each component in the balancing circuit 100, the start / stop status of each balancing line, the actual balancing mode, and the real-time voltage of the corresponding battery compartment. The real-time voltage of the battery compartment may include the battery voltage of each battery in the battery compartment and the total voltage of the battery compartment. Furthermore, the battery balancing control module 501 can determine the balancing strategy corresponding to each battery compartment based on the target balancing voltage and the real-time voltage of the battery compartment, and issue control commands to each balancing circuit 100 accordingly to control the balancing circuit 100 to use the corresponding balancing strategy to balance each battery in its corresponding battery compartment. The balancing strategy may include balancing current and balancing mode.

[0028] For example, the battery balancing control module 501 can determine the target balancing voltage based on the average battery voltage of all batteries in the energy storage system and send it to the battery balancing control unit 102. Taking the balancing process of a battery pack as an example, the battery balancing control unit 102 can determine the batteries in the corresponding battery pack that need to be balanced based on the relative relationship between the battery voltage of each battery in its corresponding battery pack and the target balancing voltage. If the balancing requirement of the battery pack is to balance batteries 6, 10, and 13, then the battery balancing control unit 102 can control the corresponding balancing circuit 100 to start the balancing operation for batteries 6, 10, and 13 in the battery pack, and at the same time set the target balancing voltage, balancing current, and balancing mode for batteries 6, 10, and 13 in battery pack A. During the balancing process, the battery balancing control unit 102 reports to the battery balancing master control module 501 the working status of each component in the balancing circuit 100, the start / stop status of each balancing line, the actual balancing mode of each started balancing line, and the real-time voltage sampling information of the battery module being balanced, thereby realizing feedback on the balancing progress and effect.

[0029] The equalization device provided in this embodiment includes a battery equalization master control module, as well as battery equalization control units and DC-AC converters corresponding one-to-one with the battery cells in the energy storage system. The battery equalization master control module can acquire the battery voltage of all batteries in the energy storage system and obtain the target equalization voltage based on the voltage of all batteries. The battery balancing control unit corresponds one-to-one with the battery compartments of the energy storage system and can be connected. The battery balancing control unit is communicatively connected to the overall battery balancing control module and can collect the real-time voltage of the corresponding battery compartment. The DC-AC converter corresponds one-to-one with multiple battery balancing control units and is communicatively connected to the corresponding battery balancing control unit and the corresponding battery compartment. The AC terminal of the DC-AC converter can be connected to an AC power source. The overall battery balancing control module obtains the balancing strategy for each battery compartment based on the target balancing voltage and the real-time voltages, and performs voltage balancing on each battery compartment separately, thus realizing the balancing operation of each battery compartment in the energy storage system. This battery balancing device is equipped with an overall battery balancing control module that works in conjunction with the battery balancing control units in each balancing circuit to perform balancing control. On the one hand, it can accurately balance the batteries in the battery compartments, improving balancing reliability; on the other hand, it can simultaneously balance the batteries in multiple battery compartments, improving balancing efficiency.

[0030] Optionally, Figure 2 This is a circuit diagram of another equalization device and its corresponding energy storage system provided in an embodiment of the present invention. Based on the foregoing embodiments, refer to... Figure 2In addition to multiple battery packs 401, the energy storage system 600 may also include a battery management system 601. The battery balancing control module 501 can also be connected to the battery management system 601 of the energy storage system 600. The battery balancing control module 501 is configured to obtain the operating condition information of the energy storage system 600 through the battery management system 601.

[0031] Specifically, the Battery Management System (BMS) 601 refers to the core control and protection component at the energy storage system 600 level. It can monitor the real-time operating status of the entire energy storage system 600, coordinate battery balancing within the system, and ensure the safe operation of the system. The BMS 601 is connected to each battery compartment 401 within the energy storage system 600, and can detect status information such as voltage, current, pressure, and operating mode of the batteries within each compartment 401. It can also control the operating status of the batteries 402 and other components within each compartment 401. The BMS 601 is also connected to the battery balancing control module 501, which can forward the operating condition information of the energy storage system 600 to the module to assist the balancing behavior of the balancing device 500. For example, the operating condition information of the energy storage system 600 includes the basic parameters and operating status parameters of the energy storage system 600 acquired or stored by the BMS 601. The basic parameters of the energy storage system 600 may include the rated capacity of all batteries 402 in the energy storage system 600 and the type of acquisition harness used to acquire battery voltage. The operating status parameters of the energy storage system 600 may include the battery voltage of all batteries 402 in the energy storage system 600.

[0032] The battery balancing control module 501 is communicatively connected to the battery management system 601 and can obtain the operating condition information of the energy storage system 600 issued by the battery management system 601. Based on this, the battery balancing control module 501 can determine the balancing requirements of the energy storage system 600 according to the operating condition information of the energy storage system 600 issued by the battery management system 601. For example, the battery balancing control module 501 can identify the batteries 402 that need to be balanced and determine the required balancing mode by comparing the battery voltages of all batteries 402 in the energy storage system 600 issued by the battery management system 601. For example, the battery balancing control module 501 can calculate the target balancing voltage of the battery 402 based on the voltage sampling data of all batteries 402 in the energy storage system 600; the battery balancing control module 501 can identify the batteries 402 whose voltage sampling data exceeds the normal voltage range as the batteries 402 that need to be balanced, and then determine whether the required balancing mode is charging balancing or discharging balancing based on the relative relationship between the battery voltage of the battery 402 and the target balancing voltage.

[0033] Furthermore, the battery balancing control module 501 can determine the balancing current of each battery 402 based on the rated capacity of all batteries 402 in the energy storage system 600 issued by the battery management system 601. For example, the balancing current can be positively correlated with the rated capacity of the battery 402. In addition, the battery balancing control module 501 can also monitor the balancing process of the balancing circuit 100 for each corresponding battery 402 based on the operating parameters of the balancing circuit 100 fed back by the battery balancing control unit 102, so that the balancing circuit 100 balances each battery 402 according to a preset balancing mode, balancing current, and balancing target voltage. For example, the operating parameters of the balancing circuit 100 may include sampled data of battery voltage, on / off status of each balancing line, and status data of the DC-AC converter 103.

[0034] In this embodiment, the battery balancing control module in the balancing device is also connected to the battery management system of the energy storage system. The battery balancing control module is configured to obtain the operating condition information of the energy storage system through the battery management system. The operating condition information of the energy storage system includes the battery voltage, rated capacity, and type of acquisition harness used to acquire battery voltage for all batteries in the energy storage system. This enables precise balancing of the energy storage system. The connection between the battery balancing control module and the battery management module allows for adaptive balancing based on the operating condition information of the energy storage system, making the balancing process more in line with the needs of the energy storage system and further improving the balancing reliability of the balancing device.

[0035] Optionally, based on the foregoing embodiments, refer to... Figure 2 Each battery balancing control unit 102 is configured with a unique device address, which helps the battery balancing master control module 501 distinguish between the various battery balancing control units 102 during communication. The battery balancing master control module 501 determines the real-time voltage of the corresponding battery compartment 401 based on the device address of the battery balancing control unit 102 and generates a balancing strategy for the corresponding battery compartment 401. The balancing strategy includes a target balancing voltage, a balancing current magnitude, and a balancing operating mode. The balancing operating modes include constant voltage or constant current charging mode and constant voltage or constant current discharging mode.

[0036] Specifically, the real-time voltage of the battery compartment 401 includes the battery voltage of each battery in the battery compartment 401 and the total voltage of the battery compartment 401. The battery balancing control module 501 can determine the target balancing voltage based on the average value of the battery voltages of all batteries in the energy storage system 600. Furthermore, the battery balancing control module 501 can determine the battery compartment 401 and the battery balancing control unit 102 corresponding to the real-time voltage based on the device address corresponding to the received real-time voltage. Then, it compares the real-time voltage with the target balancing voltage to determine the balancing operating mode of each battery in the battery compartment 401. For example, if the battery voltage is less than the target balancing voltage, the balancing mode of the corresponding battery is constant voltage or constant current charging mode; if the battery voltage is greater than the target balancing voltage, the balancing mode of the corresponding battery is constant voltage or constant current discharging mode. In addition, the battery equalization control module 501 can determine the rated capacity and the type of the acquisition harness corresponding to the battery box 401 based on the device address. Combining this information, the size of the equalization circuit 100 of each battery in the battery box 401 can be determined, thus completing the determination of the equalization strategy of the battery box 401.

[0037] In the balancing device provided in this embodiment, each battery balancing control unit is configured with a unique device address. The overall battery balancing control module determines the real-time voltage of the corresponding battery compartment based on the device address of the battery balancing control unit and generates a balancing strategy for the corresponding battery compartment. The balancing strategy includes the target balancing voltage, the balancing current magnitude, and the balancing operating mode. The balancing operating mode includes constant voltage or constant current charging mode and constant voltage or constant current discharging mode. This enables accurate differentiation of the battery balancing control units corresponding to each battery compartment in the energy storage system, improves the corresponding balancing of each battery compartment, and enhances the reliability of the balancing device.

[0038] Optionally, Figure 3 This is a circuit diagram of another equalization device provided in an embodiment of the present invention, which is based on the foregoing embodiments and combined with... Figure 2 and Figure 3 The battery balancing control module 501 includes a processing unit 5011 and a storage unit 5012. The processing unit 5011 can be connected to the battery management system 601 of the energy storage system 600. The processing unit 5011 calculates the average voltage, maximum voltage, and minimum voltage of all batteries in the energy storage system 600 based on all battery voltages; and obtains the target balancing voltage based on the average voltage, maximum voltage, and minimum voltage. The storage unit 5012 is connected to the processing unit 5011 and is used to store all battery voltages, the average voltage, the maximum voltage, and the minimum voltage.

[0039] Specifically, the processing unit 5011 refers to a component with data analysis and processing functions, which can be connected to the battery management system 601 of the energy storage system 600 and also to each battery equalization unit. The processing unit 5011 can calculate the average voltage, maximum voltage and minimum voltage of all batteries in the energy storage system 600 according to the battery voltage of all batteries in the energy storage system 600, and then determine the target equalization voltage by combining the average voltage, maximum voltage and minimum voltage. For example, the processing unit 5011 may include at least one of microprocessor, microcontroller, digital signal processor and field programmable gate array.

[0040] Optionally, Figure 4 This is a circuit diagram of a single equalization circuit in another equalization device provided by an embodiment of the present invention. Based on the foregoing embodiments, and combined with... Figure 2 and Figure 4 Each battery balancing control unit 102 can be connected to the battery compartment 401 via multiple controllable switches S. The battery balancing control unit 102 includes a voltage acquisition module 1021 and a detection module 1022. The voltage acquisition module 1021 is connected to the battery compartment 401 and is used to acquire the real-time voltage of the corresponding battery compartment 401. The detection module 1022 is connected to each controllable switch S and the corresponding DC / AC converter 103, respectively, and is used to detect the real-time status of the controllable switches S and the real-time status of the DC / AC converter 103.

[0041] Specifically, the controllable switch S is a switching device on / off of the balancing circuit of each battery. One end of its connection is connected to the DC terminal of the DC-AC converter 103, and the other end is connected to the equalization interface k in the equalization connector 101, respectively, for connecting the batteries in the battery box 401. For example, when the equalization connector 101 includes 13 equalization interfaces k, there are also 13 controllable switches S. One controllable switch S is located between the DC terminal of the DC-AC converter 103 and the equalization connector 101, and is connected to the negative terminal of each battery in the battery box 401 via the equalization connector 101; the remaining controllable switches S are located between the DC terminal of the DC-AC converter 103 and the equalization connector 101, and are respectively connected to the positive terminal of the corresponding battery in the battery box 401. The controllable switch S can switch the on / off state of its respective balancing circuit by switching its own state. For example, the controllable switch S can include at least one of MOSFET, IGBT and solid-state relay. When batteries in battery box 401 require charging equalization, the controllable switch S on the equalization line corresponding to the battery requiring equalization is turned on. The DC-AC converter 103 converts the AC power input to the AC terminal into DC power, which can then be used to charge and equalize the battery requiring equalization via the turned-on controllable switch S. Conversely, when batteries in battery box 401 require discharging equalization, the controllable switch S on the equalization line corresponding to the battery requiring discharging equalization is turned on. The DC-AC converter 103 converts the DC power input via the corresponding controllable switch S into AC power, which is then returned to the AC power system from the AC terminal, for example, to the power grid. When battery box 401 does not require equalization at all, all controllable switches S can remain off.

[0042] The voltage acquisition module 1021 refers to a voltage sampling component installed in the battery equalization control unit 102 for acquiring the real-time voltage of the battery compartment 401. The voltage acquisition module 1021 can be connected to each battery in the corresponding battery compartment 401 to detect the battery voltage. For example, the voltage acquisition module 1021 may include an operational amplifier circuit and an analog-to-digital converter circuit. The battery equalization control unit 102 may also include a voltage sampling connector 105. The voltage sampling connector 105 is provided with a sampling interface p that corresponds one-to-one with the equalization interface k on the equalization connector 101. The voltage sampling connector 105 is connected to the input terminal of the operational amplifier circuit. The sampling interface p can also be connected to its corresponding equalization interface k to realize the separate connection and voltage sampling of each battery in the battery compartment 401.

[0043] The detection module 1022 is a functional component located within the battery equalization control unit 102, used to control and detect the real-time status of the DC-AC converter 103 and the controllable switch S. The real-time status of the controllable switch S includes its on / off state and fault conditions. The real-time status of the DC-AC converter 103 includes its operating mode, the voltage level of the external power supply, and fault conditions. The operating modes include at least two types: DC-to-AC and AC-to-DC. For example, the detection module 1022 may include a control chip or integrated circuit with signal acquisition and control functions. The battery equalization control unit 102 may also include a switch connector 104, which includes a control interface t corresponding to each controllable switch S. The switch connector 104 is connected to the detection module 1022, and the control interface t of the switch connector 104 is connected to its corresponding controllable switch S, enabling the detection module 1022 to detect and control the status of the controllable switches S.

[0044] In the equalization circuit provided in this embodiment, each battery equalization control unit can be connected to the battery box via a controllable switch to achieve on / off connection. The battery equalization control unit includes a voltage acquisition module and a detection module. The voltage acquisition module can be connected to the battery box to acquire the real-time voltage of the corresponding battery box. The detection module is connected to the controllable switch and the corresponding DC-AC converter respectively to detect the real-time status of the controllable switch and the real-time status of the DC-AC converter. This realizes voltage sampling of the battery box, as well as status detection and control of each equalization line and DC-AC converter. By combining the voltage sampling signal to determine the equalization requirements, and performing status control on each equalization line and DC-AC converter according to the equalization requirements, the equalization control is made more refined, further improving the equalization reliability of the equalization equipment.

[0045] Optionally, Figure 5 This is a circuit diagram of a single equalization circuit in another equalization device provided by an embodiment of the present invention. Based on the foregoing embodiments, refer to... Figure 5 The equalization circuit 100 also includes fuses 201 corresponding to the controllable switches S. The fuses 201 are connected in series between the corresponding controllable switches S and the DC terminals of the DC-AC converter 103, and are configured to disconnect in the event of a short circuit in the equalization circuit in which they are located.

[0046] Specifically, fuse 201 refers to a short-circuit protection device installed on each equalization line. It corresponds one-to-one with the controllable switch S and is connected between the corresponding controllable switch S and the DC-AC converter 103. It can blow when the current in the equalization line exceeds the upper limit of the normal range to cut off the equalization line and prevent excessive current from damaging the battery box and related circuit components. For example, fuse 201 may include at least one of gBat type fuse 201 and aBat type fuse 201.

[0047] For example, if a short circuit occurs in a balancing circuit during the balancing process, the current in the balancing circuit will increase sharply. If the current in the balancing circuit exceeds the upper limit of the normal range, the fuse 201 in that balancing circuit will blow, thereby cutting off the balancing circuit where the fuse 201 is located, and achieving short-circuit protection for the battery box and the balancing circuit 100. In addition, if the fuse 201 is a self-resetting fuse 201, the fuse 201 can still resume conduction after the short-circuit fault in the balancing circuit is cleared, so as to restore the balancing function of the corresponding balancing circuit.

[0048] The equalization device provided in this embodiment also includes fuses that correspond one-to-one with the equalization interfaces of the equalization connectors. The fuses are connected in series between the corresponding controllable switch and the DC terminal of the DC-AC converter. The fuses are configured to trip in the event of a short circuit in the equalization line they are connected to, thus achieving short-circuit protection for the equalization line and further improving the reliability of the equalization circuit.

[0049] Optionally, Figure 6 This is a circuit diagram of a single equalization circuit in another equalization device provided by an embodiment of the present invention. Based on the foregoing embodiments, refer to... Figure 6 The DC-AC converter 103 includes a DC connector 301, a first AC connector 302, and a second AC connector 303. As the DC terminal of the DC-AC converter 103, the DC connector 301 includes DC pins corresponding one-to-one with the equalization interface k in the equalization connector 101. Each pin is connected to the corresponding equalization interface k via a corresponding controllable switch S. As the two AC terminals of the DC-AC converter 103, the first AC connector 302 and the second AC connector 303 are respectively connected to different AC power supplies with different voltage levels.

[0050] Specifically, the DC connector 301 is an external connection component provided on the DC side of the DC-AC converter 103 for outputting or connecting DC power. The DC connector 301 integrates multiple DC pins. For example, the number of DC pins can be equal to and correspond one-to-one with the number of equalization interfaces k in the equalization connector 101, thereby realizing the connection with multiple batteries in the battery box.

[0051] The first AC connector 302 and the second AC connector 303 are two external connection components provided on the AC side of the DC-AC converter 103, used for connecting or outputting AC power of different voltage levels. The number of interfaces and the withstand voltage level of the first AC connector 302 and the second AC connector 303 can be different, thereby adapting to AC power supplies of different voltage levels, realizing the connection between the equalization circuit 100 and different AC power supplies, and broadening the adaptability range of the equalization circuit 100. For example, the first AC connector 302 can be a 220V AC connector, which includes a live wire interface L1 and a neutral wire interface N1. The live wire interface L1 is configured to connect to the live wire of an external 220V AC power supply, and the neutral wire interface N1 is configured to connect to the neutral wire of an external 220V AC power supply. The second AC connector 303 can be a 380V AC connector, which connects to an external 380V AC power supply. The second AC connector 303 includes a first phase interface A, a second phase interface B, a third phase interface C, and a neutral wire interface N2. The first phase interface A is configured to connect to the first phase wire of an external 380V AC power supply, the second phase interface B is configured to connect to the second phase wire of an external 380V AC power supply, the third phase interface C is configured to connect to the third phase wire of an external 380V AC power supply, and the neutral wire interface N2 is configured to connect to the neutral wire of an external 380V AC power supply. In other embodiments, the first AC connector 302 and the second AC connector 303 can also be adapted to AC power supplies of other voltage levels such as 110V AC, which will not be described in detail here.

[0052] For example, in an energy storage system application environment with 220V AC power, the balancing circuit 100 can be connected to 220V AC power via the first AC connector 302 of the DC-AC converter 103. When a battery compartment requires balancing, the battery balancing control unit 102 can control the DC-AC converter 103 to initiate the balancing operation for the corresponding battery and control the controllable switch S on the corresponding balancing line of that battery to be turned on. When the corresponding battery needs charging balancing, the battery balancing control unit 102 controls the DC-AC converter 103 to AC-to-DC mode, that is, using the external 220V AC power to convert to DC power, and charging the battery via the controllable switch S and balancing interface k corresponding to the battery requiring balancing. When the corresponding battery needs discharging balancing, the battery balancing control unit 102 controls the DC-AC converter 103 to DC-to-AC mode, that is, converting the DC power supplied to the DC-AC converter 103 by the battery requiring balancing via the balancing interface k and controllable switch S into 220V AC power and feeding it back to the external 220V AC system of the DC-AC converter 103. During the equalization process, the battery equalization control unit 102 samples the voltage of the battery being equalized, determines the equalization progress based on the sampling results, and thus controls the operating state of the DC-AC converter 103. When the battery equalization is complete, the battery equalization control unit 102 controls the controllable switch S corresponding to the battery being equalized to open and controls the DC-AC converter 103 to shut down the equalization operation for that battery.

[0053] Similarly, in an environment where the energy storage system is used and 380V AC power is available, the balancing circuit 100 can be connected to 380V AC power via the second AC connector 303 of the AC terminal of the DC-AC converter 103. When a battery compartment requires balancing, the battery balancing control unit 102 can control the DC-AC converter 103 to initiate the balancing operation for the corresponding battery and control the controllable switch S on the corresponding balancing line of that battery to be turned on. When the corresponding battery needs charging balancing, the battery balancing control unit 102 controls the DC-AC converter 103 to AC-to-DC mode, that is, converting the external 380V AC power into DC power, and charging the battery via the corresponding controllable switch S and balancing interface k. Conversely, when the corresponding battery needs charging balancing, the battery balancing control unit 102 controls the DC-AC converter 103 to AC-to-DC mode, that is, converting the DC power supplied to the DC-AC converter 103 by the battery requiring balancing via the balancing interface k and controllable switch S into 380V AC power and feeding it back to the external 380V AC system of the DC-AC converter 103. During the equalization process, the battery equalization control unit 102 samples the voltage of the battery being equalized, determines the equalization progress based on the sampling results, and thus controls the operating state of the DC-AC converter 103. When the battery equalization is complete, the battery equalization control unit 102 controls the controllable switch S corresponding to the battery being equalized to open and controls the DC-AC converter 103 to shut down the equalization operation for that battery.

[0054] The equalization device provided in this embodiment includes a DC-AC converter comprising a first AC connector and a second AC connector, the first and second AC connectors corresponding to different voltage levels of the external AC power supply. The first AC connector includes a live wire interface and a neutral wire interface, wherein the live wire interface is configured to connect to the live wire of an external 220V AC power supply, and the neutral wire interface is configured to connect to the neutral wire of an external 220V AC power supply. The second AC connector connects to a 380V AC power supply and includes a first phase interface, a second phase interface, a third phase interface, and a neutral wire interface, wherein the first phase interface is configured to connect to the first phase wire of the external 380V AC power supply, the second phase interface is configured to connect to the second phase wire of the external 380V AC power supply, the third phase interface is configured to connect to the third phase wire of the external 380V AC power supply, and the neutral wire interface is configured to connect to the neutral wire of the external 380V AC power supply. This enables the equalization device to interface with AC power supplies of different voltage levels, broadening the compatibility range of the equalization circuit.

[0055] Optionally, Figure 7 This is a schematic diagram illustrating the connection relationship between an equalization device and its corresponding battery management system in an energy storage system, provided as an embodiment of the present invention. Based on the aforementioned embodiments, and combined with... Figure 2 and Figure 7The battery balancing control module 501 is connected to the battery management system 601, the battery balancing control module 501 is connected to the battery balancing control unit 102 of each balancing circuit 100, and the battery balancing control unit 102 is connected to the DC-AC converter 103 via a controller area network.

[0056] Specifically, the Controller Area Network (CAN) is a serial bus communication network designed for short-distance, high-reliability data transmission between industrial devices. In this application, it is used to connect the various components in the energy storage system 600, enabling control command issuance, status data uploading, and fault alarm transmission; it serves as the neural transmission network of the energy storage system 600. The essence of the CAN is to ensure real-time and stable data interaction among multiple nodes in the complex electromagnetic environment of the energy storage system 600 through differential signal transmission and priority arbitration mechanisms, adapting to the modular design and multi-device collaborative operation requirements of the energy storage system 600. Through differential signals, CRC checksums, and fault tolerance mechanisms, the CAN can resist electromagnetic interference within the energy storage system 600, preventing data loss or mistransmission and improving the reliability and real-time performance of communication transmission. Furthermore, the CAN adopts a two-wire bus topology, significantly reducing cable usage and installation complexity, and lowering production costs. In other embodiments, in addition to the communication connection method of the sampling controller local area network, the battery equalization control module 501 and the battery management system 601, the battery equalization control module 501 and the battery equalization control unit 102 of each equalization circuit 100, and the battery equalization control unit 102 and the DC-AC converter 103 can also be connected via a serial communication network or Ethernet.

[0057] In this embodiment, the battery balancing control module and the battery management system, the battery balancing control module and the battery balancing control units of each balancing circuit, and the battery balancing control units and the DC-AC converter are all connected via a controller area network (Controller Area Network). This achieves reliable communication connections between the various components in the device. The Controller Area Network, through differential signals, CRC checks, and fault tolerance mechanisms, can resist electromagnetic interference within the energy storage system, preventing data loss or mistransmission and improving the reliability and real-time performance of communication transmission. Furthermore, the Controller Area Network adopts a two-wire bus topology, eliminating the need for separate wiring to each device, significantly reducing cable usage and installation complexity, and lowering production costs.

[0058] This application also provides an equalization system. Based on the foregoing embodiments, further reference is made to... Figure 2The balancing system includes the balancing device 500 and the energy storage system 600 in any of the aforementioned embodiments. The battery balancing control module 501 of the balancing device 500 is connected to the battery management system 601 of the energy storage system 600. The multiple DC-AC converters 103 of the balancing device 500 are respectively connected to the corresponding battery boxes in the energy storage system 600.

[0059] The equalization system and equalization equipment provided in this application include a battery equalization master control module capable of acquiring the battery voltage of all batteries in the energy storage system and obtaining a target equalization voltage based on all battery voltages. Each battery equalization control unit corresponds to and can be connected to a battery compartment in the energy storage system; the battery equalization control unit is communicatively connected to the battery equalization master control module and can acquire the real-time voltage of the corresponding battery compartment; each DC-AC converter corresponds to multiple battery equalization control units and is communicatively connected to the corresponding battery equalization control unit and can also communicate with the corresponding battery compartment; the AC terminal of the DC-AC converter can be connected to an AC power source. The battery equalization master control module obtains the equalization strategy corresponding to each battery compartment based on the target equalization voltage and each real-time voltage, and performs voltage equalization on each battery compartment separately, thus realizing the equalization operation on each battery compartment in the energy storage system. The battery equalization equipment is equipped with a battery equalization master control module that works in conjunction with the battery equalization control units in each equalization circuit for equalization control. On the one hand, it can accurately equalize the batteries in the battery compartments, improving equalization reliability; on the other hand, it can simultaneously equalize the batteries in multiple battery compartments, improving equalization efficiency.

[0060] It should be understood that the various forms of processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in this invention can be executed in parallel, sequentially, or in different orders, as long as the desired result of the technical solution of this invention can be achieved, and this is not limited herein.

[0061] The specific embodiments described above do not constitute a limitation on the scope of protection of this invention. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A leveling device, characterized in that, The equalization device is used to equalize the battery voltage of an energy storage system, and includes: The battery balancing control module is capable of acquiring the battery voltage V of all batteries in the energy storage system. cell And according to all the battery voltages V cell Obtain the target equalization voltage V tgt ; Multiple battery balancing control units are provided, each corresponding to a battery compartment in the energy storage system and capable of connection. Each battery balancing control unit is communicatively connected to the overall battery balancing control module and can collect the real-time voltage V of its corresponding battery compartment. rt ; Multiple DC-AC converters correspond one-to-one with multiple battery equalization control units, and the DC-AC converters are communicatively connected to the corresponding battery equalization control units and can be connected to the corresponding battery boxes. The AC terminals of the DC-AC converters can be connected to AC power sources. The battery equalization overall control module, based on the target equalization voltage V, tgt With each of the aforementioned real-time voltages V rt Obtain the balancing strategy corresponding to each battery box to perform voltage balancing for each battery box respectively.

2. The equalization device according to claim 1, characterized in that, The battery balancing control module can also be connected to the battery management system of the energy storage system, and the battery balancing control module is configured to obtain the operating condition information of the energy storage system through the battery management system.

3. The equalization device according to claim 2, characterized in that, The operating status information of the energy storage system includes the battery voltage V of all batteries in the energy storage system. cell Rated capacity C cell and for acquiring the battery voltage V cell The type of acquisition harness.

4. The equalization device according to claim 3, characterized in that, Each of the battery balancing control units is configured with a unique device address, and the overall battery balancing control module determines the real-time voltage V of the corresponding battery compartment based on the device address of the battery balancing control unit. rt And generate a balancing strategy corresponding to the battery box.

5. The equalization device according to any one of claims 1-4, characterized in that, The equalization strategy includes a target equalization voltage V. tgt The system includes equalizing current magnitude and equalizing operating modes, wherein the equalizing operating modes include constant voltage or constant current charging mode and constant voltage or constant current discharging mode.

6. The equalization device according to claim 1, characterized in that, The battery equalization overall control module includes: The processing unit is capable of connecting to the battery management system of the energy storage system; the processing unit calculates the battery voltage V based on all the battery voltages V. cell Calculate the average voltage V of all batteries in the energy storage system. avg Maximum voltage V max and minimum voltage V min ; and according to the average voltage V avg The maximum voltage V max and the minimum voltage V min Obtain the target equalization voltage V tgt ;and A storage unit, connected to the processing unit, is used to store all of the battery voltages V. cell The average voltage V avg The maximum voltage V max and the minimum voltage V min .

7. The equalization device according to claim 1, characterized in that, Each of the battery balancing control units can be connected to the battery compartment via a controllable switch, and the battery balancing control unit includes: The voltage acquisition module can be connected to the battery box to acquire the real-time voltage V corresponding to the battery box. rt ;and The detection module is connected to the controllable switch and the corresponding DC-AC converter, respectively, and is used to detect the real-time status of the controllable switch and the real-time status of the DC-AC converter.

8. The equalization device according to claim 7, characterized in that, The real-time status of the controllable switch includes its on / off state and fault condition. The real-time status of the DC-AC converter includes its operating mode, the voltage level of the external power supply, and fault condition. The operating mode includes DC-to-AC and AC-to-DC conversion.

9. The equalization device according to claim 2, characterized in that, The battery balancing control module is connected to the battery management system, the battery balancing control module is connected to each of the battery balancing control units, and the battery balancing control units are connected to the DC-AC converter via a controller area network.

10. An equalization system, characterized in that, The system includes the equalization device and energy storage system according to any one of claims 1-9, wherein the battery equalization control module of the equalization device is connected to the battery management system of the energy storage system, and the plurality of DC-AC converters of the equalization device are respectively connected to the battery boxes of the energy storage system.

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