Energy storage system

Abstract

The utility model provides an energy storage system, which is provided with a master control cabinet and a plurality of energy storage devices, the master control cabinet comprises an alternating current bus and a plurality of molecular switches, one end of each molecular switch is respectively connected with the alternating current bus, and the molecular switches are connected in parallel. Each energy storage device comprises a converter, a battery control box and a plurality of battery modules, the converter is arranged below the battery modules, the battery control box is arranged below the battery modules, the converter is located on one side of the battery control box, and the alternating current side of the converter is connected with the other end of the corresponding molecular switch; the direct current side of the converter is connected with the battery control box, and the battery control box is connected with each battery module in series, so that the direct current sides of the plurality of energy storage devices can be converted into alternating current sides for parallel connection through the converter, the phenomenon of parallel circulation of the energy storage system caused by parallel connection of the direct current sides is avoided, and the plurality of energy storage devices are independently controlled. And the influence on the overall capacity and power output of the energy storage system can be reduced.

Description

Technical Field

[0001] The utility model relates to the field of energy storage, and particularly to an energy storage system. Background Art

[0002] With the continuous innovation of energy storage technologies, the scale and application scope of energy storage systems are also constantly expanding. Energy storage systems are increasingly widely used in power systems. Energy storage systems can improve the flexibility, reliability and economy of power systems, and promote the consumption and utilization of renewable energy.

[0003] In order to increase the capacity and power of energy storage systems, the existing technologies generally adopt a large-capacity centralized energy storage solution. Its technical solution is to connect in parallel on the low-voltage DC side, that is, directly connect multiple energy storage battery clusters in parallel on the DC bus, and then connect to the AC grid through a high-power inverter. However, the circulating current generated after multiple energy storage battery clusters are connected in parallel often causes relatively large capacity losses, reduces the service efficiency and life of the system, and the inconsistency between battery clusters also affects the overall capacity and power output of the system. Summary of the Utility Model

[0004] An object of the utility model is to solve at least one of the technical problems existing in the prior art, and to provide an energy storage system that can convert the DC sides of multiple energy storage devices into AC sides and connect them in parallel through a converter, avoiding the parallel circulating current generated by the parallel connection of the DC sides of the energy storage system, reducing the loss of the overall capacity of the energy storage system, and independently controlling between multiple energy storage devices, and also being able to improve the stability of the power output of the energy storage devices.

[0005] To achieve the above object, a first aspect of an embodiment of the utility model provides an energy storage system, including:

[0006] A main control cabinet, the main control cabinet includes an AC bus and multiple sub-switches. One end of each sub-switch is respectively connected to the AC bus, and the sub-switches are connected in parallel with each other. Each sub-switch is arranged on the front of the main control cabinet, and the sub-switches are arranged side by side;

[0007] Multiple energy storage devices, each energy storage device is arranged on one side of the main control cabinet, and the energy storage devices are arranged side by side. Each energy storage device includes a converter, a battery control box and multiple battery modules. The converter is arranged below the battery module, the battery control box is arranged below the battery module, the converter is located on one side of the battery control box, the AC side of the converter is connected to the other end of the corresponding sub-switch, the DC side of the converter is connected to the battery control box, and the battery control box is connected in series with each battery module.

[0008] Further, in some embodiments, the main control cabinet further includes a main control switch. The main control switch is disposed on the back of the main control cabinet. One end of the main control switch is connected to an external power grid, and the other end of the main control switch is connected to an AC bus.

[0009] Further, in some embodiments, the main control switch is a handle-type switch.

[0010] Further, in some embodiments, the main control cabinet further includes an energy management device. The energy management device is disposed on the front of the main control cabinet, above each molecular switch. The energy management device is communicatively connected to each energy storage device respectively, and is configured to control the independent operation of each energy storage device.

[0011] Further, in some embodiments, the communication interface of the energy management device is a CAN2.0 high-speed bus.

[0012] Further, in some embodiments, the main control cabinet further includes a display device. The display device is disposed on the front of the main control cabinet, in front of the energy management device. The display device is communicatively connected to the energy management device, and is configured to control the display of the operating state of the energy storage system.

[0013] Further, in some embodiments, the main control cabinet further includes an uninterruptible power supply. The uninterruptible power supply is disposed on the front of the main control cabinet, in front of the energy management device. The uninterruptible power supply is communicatively connected to the energy management device.

[0014] Further, in some embodiments, the battery module includes a plurality of single-cell battery cores. The single-cell battery cores are connected in series with each other, and each single-cell battery core is a lithium iron phosphate battery core.

[0015] Further, in some embodiments, the battery module includes a battery management module. The battery management module is connected to each single-cell battery core respectively, and is configured to detect the energy storage state of each single-cell battery core in real time.

[0016] An energy storage system according to an embodiment of the present utility model has at least the following beneficial effects: By providing a main control cabinet and a plurality of energy storage devices, each energy storage device is arranged on one side of the main control cabinet, and the energy storage devices are arranged side by side. The main control cabinet includes an AC bus and a plurality of branch switches. One end of each branch switch is respectively connected to the AC bus, and the branch switches are connected in parallel with each other. Each branch switch is arranged on the front of the main control cabinet, and the branch switches are arranged side by side; Each energy storage device includes a converter, a battery control box and a plurality of battery modules. The converter is arranged below the battery module, the battery control box is arranged below the battery module, the converter is located on one side of the battery control box, the AC side of the converter is connected to the other end of the corresponding branch switch, the DC side of the converter is connected to the battery control box, and the battery control box is connected in series with each battery module. Thus, the DC sides of multiple energy storage subsystems can be converted to the AC side and connected in parallel through the converter, avoiding the parallel circulation generated by the parallel connection of the DC sides of the energy storage system, reducing the loss of the overall capacity of the energy storage system, and the multiple energy storage devices are independently controlled, which can also improve the stability of the power output of the energy storage device.

[0017] Other features and advantages of the present utility model will be described in the following description, and some will become obvious from the description. The objectives and other advantages of the present utility model can be achieved and obtained through the structures specifically pointed out in the description and the drawings. Description of the Drawings

[0018] The drawings are used to provide a further understanding of the technical solutions of the present utility model, and constitute a part of the description. They are used together with the embodiments of the present utility model to explain the technical solutions of the present utility model, and do not constitute a limitation to the technical solutions of the present utility model.

[0019] The following further illustrates the present utility model in conjunction with the drawings and embodiments;

[0020] Figure 1 is an external structure diagram of an energy storage system provided by an embodiment of the present utility model;

[0021] Figure 2 is an overall circuit electrical topology diagram of an energy storage system provided by an embodiment of the present utility model;

[0022] Figure 3 is a front internal structure diagram of the main control cabinet provided by an embodiment of the present utility model;

[0023] Figure 4 is a back internal structure diagram of the main control cabinet provided by an embodiment of the present utility model;

[0024] Figure 5 is an internal structure diagram of the energy storage device provided by an embodiment of the present utility model.

[0025] Reference numerals: main control cabinet 100, AC bus 110, molecular switch 120, main control switch 130, energy management device 140, display device 150, uninterruptible power supply 160, energy storage device 200, converter 210, battery control box 220, battery module 230. Detailed implementation manners

[0026] This part will describe in detail the specific embodiments of the present utility model. The preferred embodiments of the present utility model are shown in the drawings. The function of the drawings is to supplement the description in the text part of the specification, enabling people to intuitively and vividly understand each technical feature and the overall technical solution of the present utility model. However, it should not be construed as a limitation on the protection scope of the present utility model.

[0027] In the description of the present utility model, if the first and second are described for the purpose of distinguishing technical features, they should not be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or implicitly indicating the sequence of the indicated technical features. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present utility model described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0028] In the description of the present utility model, unless otherwise clearly defined, terms such as "arrangement", "installation", and "connection" should be understood in a broad sense. Those skilled in the art can reasonably determine the specific meanings of the above terms in the present utility model in combination with the specific content of the technical solution.

[0029] With the continuous innovation of energy storage technology, the scale and application scope of energy storage systems are also constantly expanding. Energy storage systems are increasingly widely used in power systems. Energy storage systems can improve the flexibility, reliability and economy of power systems, and promote the consumption and utilization of renewable energy.

[0030] In order to increase the capacity and power of energy storage systems, the prior art generally adopts a large-capacity centralized energy storage solution. Its technical solution is to connect in parallel on the low-voltage DC side, that is, directly connect multiple energy storage battery clusters in parallel on the DC bus, and then connect to the AC grid through a high-power inverter. However, the circulating current generated after multiple energy storage battery clusters are connected in parallel often causes a large capacity loss, reducing the service efficiency and life of the system. In addition, the inconsistency between battery clusters will also affect the overall capacity and power output of the system.

[0031] Based on this, an embodiment of the present utility model provides an energy storage system. By providing a master control cabinet and a plurality of energy storage devices, each energy storage device is arranged on one side of the master control cabinet, and the energy storage devices are arranged side by side. The master control cabinet includes an AC bus and a plurality of molecular switches. One end of each molecular switch is respectively connected to the AC bus, and the molecular switches are connected in parallel with each other. Each molecular switch is arranged on the front of the master control cabinet, and the molecular switches are arranged side by side; each energy storage device includes a converter, a battery control box and a plurality of battery modules. The converter is arranged below the battery module, the battery control box is arranged below the battery module, the converter is located on one side of the battery control box, the AC side of the converter is connected to the other end of the corresponding molecular switch, the DC side of the converter is connected to the battery control box, and the battery control box is connected in series with each battery module. Thus, the DC sides of multiple energy storage subsystems can be converted to the AC side through the converter and then connected in parallel, avoiding the parallel circulating current generated by the parallel connection of the DC sides of the energy storage system, reducing the loss of the overall capacity of the energy storage system, and independently controlling between multiple energy storage devices, which can also improve the stability of the power output of the energy storage device.

[0032] Therefore, the embodiments of the present utility model will be further described below in conjunction with the accompanying drawings.

[0033] Refer to Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 and Figure 5 shown in Figure 1 is the external structure diagram of an energy storage system provided by an embodiment of the present utility model, Figure 2 is the overall circuit electrical topology diagram of an energy storage system provided by an embodiment of the present utility model, Figure 3 is the front internal structure diagram of the master control cabinet provided by an embodiment of the present utility model, Figure 4 is the back internal structure diagram of the master control cabinet provided by an embodiment of the present utility model, Figure 5It is the internal structure diagram of the energy storage device provided by the embodiment of the present utility model. The energy storage system includes a general control cabinet 100 and a plurality of energy storage devices 200. Each energy storage device 200 is arranged on one side of the general control cabinet 100, and the energy storage devices 200 are arranged side by side. The general control cabinet 100 includes an AC bus 110 and a plurality of branch switches 120. One end of each branch switch 120 is respectively connected to the AC bus 110, and the branch switches 120 are connected in parallel with each other. Each branch switch 120 is arranged on the front of the general control cabinet 100, and the branch switches 120 are arranged side by side; each energy storage device 200 includes a converter 210, a battery control box 220 and a plurality of battery modules 230. The converter 210 is arranged below the battery module 230, the battery control box 220 is arranged below the battery module 230, the converter 210 is located on one side of the battery control box 220, the AC side of the converter 210 is connected to the other end of the corresponding branch switch 120, the DC side of the converter 210 is connected to the battery control box 220, and the battery control box 220 is connected in series with each battery module 230, thereby physically cutting off the circulation path between the energy storage device 200 and the AC bus 110, avoiding the parallel circulation generated by the parallel connection of the DC sides of the energy storage system, and reducing the overall capacity loss of the energy storage system.

[0034] It should be noted that the energy storage system stores energy through a plurality of energy storage devices 200, realizing the modularization and refinement of the energy storage system, that is, decomposing the energy storage system into a plurality of relatively independent energy storage devices 200. Each energy storage device 200 can be controlled and optimized according to its own characteristics and requirements. At the same time, each energy storage device 200 can be flexibly combined and disassembled to achieve the scalability and maintainability of the energy storage system.

[0035] Furthermore, from Figure 2 and Figure 4 it can be seen that the general control cabinet 100 further includes a main control switch 130. The main control switch 130 is arranged on the back of the general control cabinet 100. One end of the main control switch 130 is connected to the external power grid, and the other end of the main control switch 130 is connected to the AC bus 110, thereby being able to control the access of the grid power supply to the energy storage system and ensuring the safety and reliability of the energy storage system.

[0036] Furthermore, from Figure 4 it can be seen that the main control switch 130 is a handle-type switch, thereby being able to facilitate the operation of the main control switch 130 by the staff.

[0037] Furthermore, from Figure 2 and Figure 3It can be seen that the main control cabinet 100 further includes an energy management device 140. The energy management device 140 is arranged on the front of the main control cabinet 100, above each molecular switch 120. The energy management device 140 is communicatively connected to each energy storage device 200 respectively, and is used to control the independent operation of each energy storage device 200, so as to independently control, optimize and manage each energy storage device 200, and improve the stability of the power output of the energy storage device 200.

[0038] It should be noted that the communication interface of the energy management device 140 is a CAN2.0 high-speed bus, which can improve the transmission rate and transmission stability between the energy management device 140 and each energy storage device 200.

[0039] It also should be noted that the energy management device 140 exchanges data and transmits instructions with the battery control box 220 and the converter 210 of each energy storage device 200 through the CAN2.0 high-speed bus. On the one hand, the energy management device 140 can collect various data and parameters of the energy storage device 200, such as collecting the voltage, current, temperature, SOC, SOH, working status, etc. of the battery module 230; or collecting the voltage, current, power, working status, etc. of the converter 210; or collecting the total power, total current, etc. of the energy storage device 200. On the other hand, the energy management system can also send parameter settings, control commands, execution power, etc. to the battery control box 220 and the converter 210 of each energy storage device 200 to achieve the optimal operation of the energy storage system and ensure the safety and stability of the energy storage system.

[0040] Furthermore, from Figure 2 and Figure 3 It can be seen that the main control cabinet 100 further includes a display device 150. The display device 150 is arranged on the front of the main control cabinet 100, in front of the energy management device 140. The display device 150 is communicatively connected to the energy management device 140, and is used to control and display the operating state of the energy storage system, so as to improve the visualization ability of the energy storage system and facilitate the staff to obtain relevant data of the energy storage system.

[0041] Furthermore, from Figure 2 and Figure 3 It can be seen that the main control cabinet 100 further includes an uninterruptible power supply 160. The uninterruptible power supply 160 is arranged on the front of the main control cabinet 100, in front of the energy management device 140. The uninterruptible power supply 160 is communicatively connected to the energy management device 140, and can provide a working power supply for the energy storage system to ensure the reliable operation of the equipment. When the external power grid loses power, the uninterruptible power supply 160 can continue to supply power to the energy storage system through battery inversion output.

[0042] It should be noted that the battery module 230 includes a plurality of single cells (not labeled), and the single cells are connected in series with each other. Each single cell is a lithium iron phosphate battery cell, thereby improving the reliability and safety of the battery module 230.

[0043] Furthermore, the battery module 230 includes a battery management module (not labeled). The battery management module is respectively connected to each single cell, and is used to detect the energy storage state of each single cell in real time, thereby improving the reliability and safety of the battery module 230.

[0044] It should be understood that in the present utility model, "at least one (item)" means one or more, and "a plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that there can be three relationships. For example, "A and / or B" can represent: only A exists, only B exists, and both A and B exist at the same time. Among them, A and B can be singular or plural. The character " / " generally represents an "or" relationship between the associated objects before and after. "At least one (item) of the following" or its similar expressions refer to any combination of these items, including any combination of single item (item) or plural items (items). For example, at least one (item) of a, b or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0045] In several embodiments provided by the present utility model, it should be understood that the disclosed system and principle method can be implemented in other ways. For example, the system embodiments described above are only illustrative. For example, the above-mentioned unit division is only a logical function division. In actual implementation, there can be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling or direct coupling or communication connection to each other can be through some interfaces, and the indirect coupling or communication connection of devices or units can be in electrical, mechanical or other forms.

[0046] The units described above as separated components may or may not be physically separated. The components displayed as units may or may not be physical units, that is, they can be located in one place, or can be distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0047] In addition, in each embodiment of the present utility model, each functional unit can be integrated into a processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

[0048] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present utility model, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes multiple instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods in each embodiment of the present utility model.

[0049] The embodiments of the present utility model have been described in detail above with reference to the drawings. However, the present utility model is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present utility model within the scope of knowledge possessed by those of ordinary skill in the art.

Claims

1. An energy storage system, characterized in that ,include: A main control cabinet, the main control cabinet comprises an AC bus and a plurality of molecular switches, one end of each of the molecular switches is respectively connected to the AC bus, each of the molecular switches is connected in parallel with each other, each of the molecular switches is arranged on the front of the main control cabinet, and each of the molecular switches is arranged in parallel; Multiple energy storage devices, each of which is arranged on one side of the main control cabinet, and each of the energy storage devices is arranged side by side. Each of the energy storage devices includes a converter, a battery control box and multiple battery modules. The converter is arranged below the battery module, and the battery control box is arranged below the battery module. The converter is located on one side of the battery control box, and the AC side of the converter is connected to the other end of the corresponding molecular switch, and the DC side of the converter is connected to the battery control box, and the battery control box is connected in series with each of the battery modules.

2. The energy storage system according to claim 1, characterized in that: The main control cabinet also includes a main control switch, which is arranged on the back of the main control cabinet. One end of the main control switch is connected to the external power grid, and the other end of the main control switch is connected to the AC bus.

3. The energy storage system according to claim 2, characterized in that: The main control switch is a handle type switch.

4. The energy storage system according to claim 1, characterized in that: The main control cabinet also includes an energy management device, which is arranged on the front of the main control cabinet. The energy management device is located above each of the molecular switches. The energy management device is respectively communicated with each of the energy storage devices, and the energy management device is used to control each of the energy storage devices to operate independently.

5. The energy storage system according to claim 4, characterized in that: The communication interface of the energy management device is a CAN2.0 high-speed bus.

6. The energy storage system according to claim 4, characterized in that: The main control cabinet also includes a display device, which is arranged on the front of the main control cabinet. The display device is located in front of the energy management device. The display device is communicatively connected to the energy management device, and is used to control and display the operating status of the energy storage system.

7. The energy storage system according to claim 4, characterized in that: The main control cabinet also includes an uninterruptible power supply, which is arranged on the front of the main control cabinet and in front of the energy management device. The uninterruptible power supply is communicatively connected with the energy management device.

8. The energy storage system according to claim 1, characterized in that: The battery module includes a plurality of single cells, each of which is connected in series, and each of which is a lithium iron phosphate cell.

9. The energy storage system according to claim 8, characterized in that: The battery module comprises a battery management module, which is respectively connected to each of the single cells and is used to detect the energy storage status of each of the single cells in real time.

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