CN117578539A

CN117578539A - Energy storage system

Info

Publication number: CN117578539A
Application number: CN202311498280.9A
Authority: CN
Inventors: 叶正民; 谷鹏; 杨益; 罗来明
Original assignee: Hunan Megmit Electric Technology Co ltd; Shenzhen Megmeet Electrical Co Ltd
Current assignee: Hunan Megmit Electric Technology Co ltd; Shenzhen Megmeet Electrical Co Ltd
Priority date: 2023-11-10
Filing date: 2023-11-10
Publication date: 2024-02-20

Abstract

The present application provides an energy storage system, the energy storage system comprising: a confluence module; each energy module comprises a transduction unit, an energy switch unit and a battery unit which are sequentially connected, and the transduction unit is connected with the confluence module; the control module comprises a plurality of main control units, and each main control unit is connected with a corresponding energy switch unit to control the on or off of the energy switch unit. Through the system, the multistage independent control of the energy modules can be realized, so that the circulation problem and the safety problem caused by energy collection are avoided.

Description

Energy storage system

Technical Field

The application relates to the technical field of battery energy storage, in particular to an energy storage system.

Background

With the global energy supply problem and the increasing exhaustion of non-renewable energy sources such as global fossil energy sources and the like, and the accompanying influence on environment, climate and the like, the use of renewable energy sources such as electric power and the like is increasingly important and widespread, while an energy storage system is an important ring in 'collection-transmission-distribution-use-storage' in electric power production, a centralized energy storage system adopts MW-level high-power DC/AC, batteries are independently designed by battery cabinets or battery frames and are integrated in containers, however, the centralized arrangement of the batteries is easy to expand fire when fire occurs, and on the other hand, partial batteries cannot work at ideal temperature due to temperature imbalance, thereby further causing the difference of battery Charge States (SOCs).

At present, large-scale battery packs are generally adopted in a large-scale energy storage system to convert power in a serial-parallel connection mode by utilizing a centralized energy storage converter, the system architecture has higher requirement on the consistency of batteries, a barrel effect is easily caused in a multi-stage series flow structure, namely, the system performance is determined by the worst battery, if the system is in a parallel connection mode of a plurality of battery packs, local overheating is easily caused by energy collection, so that the safety problem is induced, and the connection among the plurality of battery packs also causes a circulation problem caused by mutual charge and discharge in the plurality of battery packs, so that the storage or release of electric energy is not facilitated.

Disclosure of Invention

The present application is directed to an energy storage system to solve the problem of circulation current existing in the current energy storage system and the safety problem caused by energy collection generated in the process of confluence.

To solve the above-mentioned problems, the present application provides an energy storage system, which includes: a confluence module; each energy module comprises a transduction unit, an energy switch unit and a battery unit which are sequentially connected, and the transduction unit is connected with the confluence module; the control module comprises a plurality of main control units, and each main control unit is connected with a corresponding energy switch unit to control the on or off of the energy switch unit.

In an embodiment, the energy switch unit comprises a main positive switch and a main negative switch, the main positive switch is arranged between the positive electrode of the energy conversion unit and the positive electrode of the battery unit, and the main negative switch is arranged between the negative electrode of the energy conversion unit and the negative electrode of the battery unit.

In one embodiment, the battery unit includes a plurality of battery packs; the control module further comprises a plurality of slave control units, and each slave control unit is connected with a corresponding battery pack to acquire battery information of the corresponding battery pack.

In one embodiment, the bus module includes a plurality of ac switch units, a first end of each ac switch unit is connected to the bus terminal, and a second end of each ac switch unit is connected to the transducer unit of the partial energy module.

In an embodiment, the control module further comprises a master control unit, and the master control unit is connected with the transduction unit, the master control unit, the slave control unit and the alternating current switch unit.

In order to solve the above problems, the present application further provides an energy storage system control flow for controlling the energy storage system to perform up-down current process operation.

In an embodiment, the master control unit is configured to: detecting the state of an alternating current switch unit; when the alternating current switch unit is closed, a first power-on instruction is sent to the transduction unit so as to enable the transduction unit to be electrified; and when the energy conversion unit finishes powering up, a second power-up instruction is sent to the main control unit, so that the main control unit controls the energy module to be powered up.

In an embodiment, the master control unit is configured to perform a self-test before detecting the state of the ac switching unit.

In an embodiment, the master control unit is configured to: when a second power-on instruction is received, closing a main negative switch; when the main negative switch is closed, closing the main positive switch; and feeding back power-on completion information when the main positive switch is closed.

In an embodiment, the master control unit is configured to: when receiving the power-down signal, sending a shutdown instruction to the transduction unit so as to shutdown the transduction unit; when the energy conversion unit finishes stopping, a power-down instruction is sent to the main control unit, so that the main control unit controls the energy module to power down; and when the energy module finishes power-down, the alternating current switch unit is controlled to be turned off.

In an embodiment, the master control unit is configured to: detecting a current value when a power-down instruction is received; if the current value is smaller than the set value, the main positive switch is disconnected, and if the current value is larger than the set value, the main positive switch is disconnected in a delay mode; the main negative switch is opened in a delayed manner; and after at least one of the main positive switch and the main negative switch is completely disconnected, feeding back power-down completion information.

There is provided by the present application an energy storage system comprising: a confluence module; each energy module comprises a transduction unit, an energy switch unit and a battery unit which are sequentially connected, and the transduction unit is connected with the confluence module; the control module comprises a plurality of main control units, and each main control unit is connected with a corresponding energy switch unit to control the on or off of the energy switch unit.

Through above-mentioned system structure, adopt modular structure, realize the multistage independent storage control of energy with the form of multibranch, with the circulation problem that forms of mutual charge and discharge between solving multistage energy parallel, and reduce the conflux energy flow that multistage energy collection formed and probably exist and lead to local overheat to cause the safety problem that fires caused, and the free design combination of energy storage system according to the demand can be realized to the structure of multibranch, satisfy multiple user demand, applicable scope is wider, and adopt the parallelly connected mode of multibranch can reduce the energy flow of conflux, reduce the specification and then reduce cost of busbar.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art. Wherein:

FIG. 1 is a schematic diagram of an embodiment of an energy storage system provided herein;

FIG. 2 is a schematic diagram of an energy module structure of an embodiment of an energy storage system provided herein;

FIG. 3 is a schematic diagram of a second embodiment of an energy storage system provided herein;

FIG. 4 is a schematic diagram of a third embodiment of an energy storage system provided herein;

FIG. 5 is a schematic diagram of the overall current flow of an embodiment of the energy storage system provided herein;

FIGS. 6a and 6b are schematic views showing the power-up sub-processes of the control and main control units in FIG. 5;

FIG. 7 is a schematic diagram of an upper current path of an energy module of an embodiment of an energy storage system provided herein;

FIG. 8 is a schematic diagram of an upper current path of an energy module according to a second embodiment of the energy storage system provided herein;

FIG. 9 is a schematic diagram of a system down current flow of an embodiment of an energy storage system provided herein;

FIGS. 10a and 10b are schematic illustrations of the control of the power down and energy module of the power down control unit of FIG. 9;

fig. 11 is a schematic view of a current flow under an energy module of an embodiment of an energy storage system provided in the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It is to be understood that the specific embodiments described herein are for purposes of illustration only and are not limiting. It should be further noted that, for convenience of description, only some, but not all of the structures related to the present application are shown in the drawings. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments herein without making any inventive effort, are intended to be within the scope of the present application.

The terms "first," "second," and the like in this application are used for distinguishing between different objects and not for describing a particular sequential order. Furthermore, the terms "comprise" and "have," as well as any variations thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those listed steps or elements but may include other steps or elements not listed or inherent to such process, method, article, or apparatus.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.

Along with the wide application of renewable energy sources such as electric power, in daily life and in the power supply of large-scale equipment, for example, mobile equipment such as electric automobiles, in order to meet the energy storage and energy supply requirements of the equipment, the application provides an energy storage system so as to solve the problems of energy flow collection caused in the series-parallel connection of battery packs and circulation existing in the mutual charging and discharging of a plurality of battery packs in the existing large-scale energy storage system.

Referring to fig. 1 and 2, fig. 1 is a schematic structural diagram of an embodiment of an energy storage system provided in the present application; fig. 2 is a schematic structural diagram of an energy module of an embodiment of an energy storage system provided in the present application. Specifically, the energy storage system structure includes: a bus module 10, an energy module 20, and a control module 30; wherein, each energy module 20 of the plurality of energy modules 20 comprises a transduction unit 21, an energy switch unit 22 and a battery unit 23 which are sequentially connected, and the transduction unit 21 is connected with the confluence module 10; the control module 30 includes a plurality of main control units 32, and each main control unit 32 is connected to a corresponding energy switch unit 22 to control on or off of the energy switch unit 22; to achieve multi-level independent control of the energy modules 20 and to improve the safety performance of the energy storage system.

Optionally, in an embodiment, the energy conversion unit 21 may use an energy storage converter, specifically, an energy storage converter (PCS, power Conversion System) is also called a bidirectional energy storage inverter, and the device for implementing bidirectional conversion of electric energy connected between the battery system and the power grid (and/or load) is a core component for implementing bidirectional flow of electric energy between the energy storage system and the power grid, and is used for controlling the charging and discharging processes of the battery to perform ac-dc conversion; the working principle is that the alternating current/direct current device is a four-quadrant running converter with controllable alternating current and direct current sides, and the alternating current/direct current conversion of electric energy is realized. The principle is that constant power or constant current control is carried out through a microgrid monitoring instruction to charge or discharge a battery, and meanwhile, the output of fluctuation power sources such as wind power, solar energy and the like is smoothed; the PCS has the main functions of overvoltage and undervoltage, overload, overcurrent, short circuit, overtemperature and the like, has island detection capability to perform mode switching, realizes the communication function of an upper control system and an energy exchanger, and performs grid-connected and off-grid smooth switching control and the like; the converter unit 21 may also adopt other bidirectional inverter conversion devices to achieve the functions thereof, i.e. to meet the requirements and conditions of the embodiments herein, which are not limited herein.

Alternatively, in an embodiment, the energy switch unit 22 includes a main positive switch 221 and a main negative switch 222, the main positive switch 221 is disposed between the positive electrode of the transduction unit 21 and the positive electrode of the battery unit 23, and the main negative switch 222 is disposed between the negative electrode of the transduction unit 21 and the negative electrode of the battery unit 23. Specifically, in an embodiment, the main positive switch 221 and the main negative switch 222 are both disposed in a high-voltage box included in the energy module 20, so as to control on-off power-on/off of the energy module 20.

Optionally, in an embodiment, the main positive switch 221 and the main negative switch 222 are controlled to be turned on or off by the command signal of the main control unit 32, so that the corresponding energy module 20 completes separate up-down current paths, and independent control of the energy module 20 is achieved.

Optionally, in an embodiment, the energy switch unit 22 is further provided with a fuse 223, where the fuse 223 is configured to fuse the line when the current in the line is too large, and the fuse melts with heat generated by itself after the current exceeds a specified value for a period of time, so as to break the circuit and protect the circuit; in some embodiments, the fuse 223 may employ a circuit protection function including, but not limited to, other types of overcurrent protectors to achieve a circuit protection function when the current in the system exceeds a predetermined maximum value, and is not specifically limited herein.

Alternatively, in an embodiment, the battery unit 23 includes a plurality of battery packs 231; the control module 30 further includes a plurality of slave control units 33, and each slave control unit 33 is connected to a corresponding battery pack 231 to obtain battery information of the corresponding battery pack 231. In some embodiments, the battery pack 231 may be a battery including, but not limited to, a lead-acid battery, a nickel-cadmium battery, a nickel-hydrogen battery, and a lithium ion battery, which are not particularly limited herein.

Alternatively, in an embodiment, the bus module 10 includes a plurality of ac switch units 11, a first end of each ac switch unit 11 is connected to the bus terminal, and a second end of each ac switch unit 11 is connected to the transducer unit 21 of the partial energy module 20.

Optionally, in an embodiment, the control module 30 further includes a master control unit 31, and the master control unit 31 is connected to the transduction unit 21, the master control unit 32, the slave control unit 33, and the ac switch unit 11. The master control unit 31 is used for controlling the connection and conduction relation of the overall power up and power down of the system so as to realize the control function of the overall power up and power down of the energy storage system 100.

Optionally, in an embodiment, the master control unit 31 may use a BMS control system, specifically, a battery management system (Battery Management System) of BMS, that is, manage charging and discharging of the battery, so that the battery is in an optimal state, and since the battery cells are an electrochemical process, a plurality of battery cells form a battery, and since each battery cell characteristic, no matter how precise each battery cell is manufactured, there are places where errors and inconsistencies in the usage time, the battery management system evaluates the current state of the battery through limited parameters. The BMS has many applications, and for large-scale battery systems, there are two general types, one type is the application of automobiles, and the other type is the application of energy storage; the three-layer architecture of the BMS system comprises a single battery management layer BMU, a battery pack management layer BCMU and a battery pack (multiple groups) management layer BAMS; wherein the management layer of the battery pack 231 is also called a PCS battery unit management layer; other control systems may be adopted for the master control unit 31, which may meet the requirements and conditions of the embodiments herein, and are not limited herein.

Optionally, in an embodiment, as shown in fig. 3, fig. 3 is a schematic structural diagram of a second embodiment of the energy storage system provided in the present application; specifically, the bus module 10 includes two branches, where the two branches correspond to two ac switch units 11, where a plurality of energy modules 20 may be connected under each ac switch unit 11, and the number of energy modules 20 may be freely selected according to actual use requirements or design schemes, which is not limited herein.

Optionally, in an embodiment, as shown in fig. 4, fig. 4 is a schematic structural diagram of a third embodiment of the energy storage system provided in the present application; it can be understood that the energy storage system 100 may be further configured that a plurality of branches correspond to a plurality of ac switch units 11, and a plurality of energy modules 20 may be connected under each ac switch unit 11, where the number of ac switch units 11 may be freely selected according to actual use requirements or design schemes, which is not limited herein; the number of the energy modules 20 can be freely selected according to the actual use requirement or design scheme, and is not particularly limited herein; the ac switch units 11 on different numbers of branches and the energy modules 20 of different numbers are combined by adopting different schemes, so that the energy storage system 100 meeting different requirements can be freely combined according to modularization.

Optionally, in an embodiment, a high-precision ammeter is arranged in the convergence cabinet and is arranged at a grid-connected point of the convergence cabinet, so that grid power can be accurately detected; in other embodiments, the master control unit 31 is also disposed in the bus cabinet.

It can be appreciated that, the above energy storage system 100 can realize a modularized structure, and realize multi-stage independent storage control of energy in a multi-branch manner, so as to solve the problem of circulation formed by mutual charge and discharge between multi-stage energy parallel connection, and reduce the safety problem caused by local overheat initiation fire possibly existing in the converged energy flow formed by multi-stage energy convergence.

Referring to fig. 5, fig. 5 is a schematic view of the overall current flow of the system according to an embodiment of the energy storage system provided in the present application; corresponding to the energy storage system described in the above description, a set of control procedures applied to the energy storage system is also designed correspondingly, wherein the control operation is implemented by the control module 30.

Optionally, in an embodiment, the master control unit 31 is configured to: detecting the state of the ac switch unit 11; when the alternating current switch unit 11 is closed, a first power-on instruction is sent to the transduction unit 21 so as to enable the transduction unit 21 to be powered on; when the energy conversion unit 21 finishes powering up, a second power-up instruction is sent to the main control unit 32, so that the main control unit 32 controls the energy module 20 to be powered up.

Optionally, in an embodiment, the master control unit 31 is configured to perform a self-test before detecting the state of the ac switching unit 11. Specifically, the self-checking content comprises: and detecting no fault condition by the low-voltage power supply and receiving no other fault information.

Referring to fig. 5, fig. 6a, and fig. 6b, fig. 6a and fig. 6b are schematic views of a sub-flow of the control and the main control units in fig. 5 for power-up.

It can be understood that the specific current process on the system is that, after the power-up operation is performed, the system master control unit 31 is powered on at a low voltage, and after the power-up, the master control unit 31 starts to perform self-checking, detects the actuation states of the plurality of ac switch units 11 in the ac module after the self-checking is passed, determines that the power-up fails if the state of the ac switch unit 11 is detected to be off, and sends an instruction for powering up the energy conversion unit 21 if the state of the ac switch unit 11 is detected to be on, so as to control the energy conversion unit 21 to perform the power-up operation; after the power-on operation of the energy conversion unit 21, feeding back the power-on state of the energy conversion unit 21 to the main control unit 31, judging that the power-on fails if the energy conversion unit 21 is detected to be in the standby state, and controlling the secondary main control unit 32 to perform the power-on operation if the energy conversion unit 21 is detected to be in the power-on state; the secondary main control unit 32 is sent to operate with a power-on instruction, after the main control unit 32 receives the general control power-on instruction, the main control unit performs self-checking, controls the battery unit 23 to power on after the self-checking is passed, and feeds back the power-on state of the battery unit 23, if the power-on feedback of the battery unit 23 is received within a set time, the power-on is completed, if the feedback is not received, the power-on failure is judged, wherein the set time is set according to the actual requirement or the set scheme, for example, the feedback is performed within 30 seconds, the specific time is specifically set, and the specific time is not limited.

Alternatively, in an embodiment, the control of the ac switch unit 11 and the energy conversion units 21 and the main control units 32 in the energy modules 20 after the total control self-checking may be that the plurality of energy modules 20 perform simultaneous control operations, and the operations between the energy modules 20 are independent and do not affect each other, so that the power-on and power-off operation determination manners of the energy modules 20 are the same.

Optionally, in an embodiment, as shown in fig. 7 and 8, fig. 7 is an upper current schematic diagram of an energy module of an embodiment of the energy storage system provided in the present application; FIG. 8 is a schematic diagram of an upper current path of an energy module according to a second embodiment of the energy storage system provided herein; as shown in fig. 7, the main control unit 32 is configured to: upon receiving the second power-on instruction, the main negative switch 222 is closed; when the main negative switch 222 is completed to be closed, the main positive switch 221 is closed; when the main positive switch 221 is completed to be closed, power-on completion information is fed back. Specifically, in another embodiment, as shown in fig. 8, after receiving the power-on instruction issued by the master control unit 31, the master control unit 32 is powered on at a low voltage and performs a self-checking operation, and the master control unit 32 performs a master control self-checking process after the power is powered on at the low voltage, where the content of the self-checking includes: after low-voltage power is obtained, the self-detection of fault-free conditions and the failure of other fault information are not received; after the self-checking of the system of the main control unit 32 is finished, the corresponding main negative switch 222 is controlled to be closed, whether the switch state of the main negative switch 222 is closed is detected after the operation is finished, if the state of the main negative switch 222 is detected to be open, the power-on failure is judged, the switch failure of the main negative switch 222 is fed back to the main control unit 32, and if the state of the main negative switch 222 is detected to be closed, the operation of closing the main positive switch 221 is executed; after the operation is completed, whether the switch state of the main positive switch 221 is closed is detected, if the state of the main positive switch 221 is detected to be open, the power-on failure is determined, the switch failure of the main positive switch 221 is fed back to the main control unit 32, and if the switch state of the main positive switch 221 is detected to be closed, the high-voltage power-on success is determined, and the high-voltage state is fed back.

Referring to fig. 9, 10a and 10b, fig. 9 is a schematic diagram illustrating a current flow under the system according to an embodiment of the energy storage system provided in the present application; fig. 10a and 10b are schematic illustrations of the control of the shutdown of the transduction unit and the power down of the control energy module of fig. 9.

Optionally, in an embodiment, the master control unit 31 is configured to: upon receiving the power-down signal, a shutdown instruction is sent to the transduction unit 21 to shutdown the transduction unit 21; when the energy conversion unit 21 finishes stopping the power-down, a power-down instruction is sent to the main control unit 32, so that the main control unit 32 controls the energy module 20 to power down; when the power module 20 is powered down, the ac switching unit 11 is controlled to be turned off.

Optionally, in an embodiment, the lower current Cheng Juti of the system is: after detecting the power-down command signal, the energy conversion unit 21 is controlled to perform a power-down operation, as shown in fig. 10a, the energy conversion unit 21 performs the power-down operation after receiving the power-down command signal, and feeds back the power-down state of the energy conversion unit 21 after the power-down operation to the master control unit 31, the master control unit 31 further controls the corresponding energy module 20 to perform the power-down operation after detecting that the energy conversion unit 21 is stopped, as shown in fig. 10b, the master control unit 32 controls the corresponding battery unit 23 to perform the power-down operation after receiving the power-down signal of the energy module 20, feeds back the power-down state of the battery unit 23 to the master control unit 31 after performing the power-down operation, and disconnects the corresponding ac switch unit 11 after receiving the power-down signal of the energy module 20, if the state of the ac switch unit 11 is detected to be closed, determines that a fault is detected and uploads a fault problem, and if the state of the ac switch unit 11 is detected to be opened, determines that the power-down is completed.

The power-down process of the corresponding system may include performing power-down operations on a plurality of energy modules 20 at the same time, where operations between the energy modules 20 are independent and do not affect each other, and power-up and power-down operation determination modes of the energy modules 20 are the same, and when power-down of all the energy modules 20 in the corresponding system is successful and the corresponding states of all the ac switch units 11 are disconnected, power-down of the system is successful as a whole.

Referring to fig. 11, fig. 11 is a schematic view of a current flow under an energy module of an embodiment of an energy storage system provided in the present application.

Optionally, in an embodiment, the master control unit 32 is configured to: detecting a current value when a power-down instruction is received; if the current value is smaller than the set value, the main positive switch 221 is turned off, and if the current value is larger than the set value, the main positive switch 221 is turned off in a delayed manner; the main negative switch 222 is opened in a delayed manner; after at least one of the main positive switch 221 and the main negative switch 222 is completed to be turned off, power-down completion information is fed back.

Optionally, in an embodiment, it can be appreciated that the lower current Cheng Juti of the energy module 20 is:

detecting the current after receiving a power-down instruction of the main control, detecting whether the current value is smaller than a set value, starting a mode of disconnecting the main positive switch 221 in a time delay manner when the detected current value is larger than the set value, and directly disconnecting the main positive switch 221 when the detected current value is smaller than the set value; after the operation of opening the main positive switch 221 is performed, detecting the state of the main positive switch 221, if the state of the main positive switch 221 is detected to be closed, feeding back that the opening fault of the main positive switch 221 possibly has adhesion, and meanwhile, forcibly opening the main negative switch 222, and if the state of the main positive switch 221 is detected to be opened, adopting the operation of delaying to open the main negative switch 222; after the operation on the main negative switch 222 is performed, the switch state of the main negative switch 222 is detected, if the state of the main negative switch 222 is detected to be closed, the blocking possibly exists in the open fault of the feedback main negative switch 222, if the state of the main negative switch 222 is detected to be open, the main positive switch 221 and the main negative switch 222 are simultaneously detected, if at least one of the switches is detected to be open, the high-voltage down is judged to be successful, the high-voltage state is fed back in real time, and if the main positive switch 221 and the main negative switch 222 are detected to be both closed, the power-down failure is judged, and the high-voltage state is fed back in real time.

Through foretell energy storage system device and corresponding operation mode, can realize adopting modular structure, realize the multistage independent storage control of energy with the form of multibranch, with the circulation problem that forms of mutual charge and discharge between solving multistage energy parallel, and reduce the conflux energy flow that multistage energy collection formed and probably exist and lead to local overheat to cause the safety problem that causes the fire, and the energy storage system can be realized according to the demand and freely design the combination to the structure of multibranch, satisfy multiple user demand, applicable scope is wider, and adopt the parallelly connected mode of multibranch can reduce the energy flow of conflux, reduce the specification of busbar and then reduce cost.

The foregoing has outlined rather broadly the more detailed description of embodiments of the present application, wherein specific examples are provided herein to illustrate the principles and embodiments of the present application, the above examples being provided solely to assist in the understanding of the methods of the present application and the core ideas thereof; meanwhile, those skilled in the art will have variations in the specific embodiments and application scope in light of the ideas of the present application, and the present description should not be construed as limiting the present application in view of the above.

Claims

1. An energy storage system, the energy storage system comprising:

a confluence module;

each energy module comprises a transduction unit, an energy switch unit and a battery unit which are sequentially connected, and the transduction unit is connected with the confluence module;

the control module comprises a plurality of main control units, and each main control unit is connected with a corresponding energy switch unit to control the on or off of the energy switch unit.

2. The energy storage system of claim 1, wherein the energy switch unit comprises a main positive switch disposed between a positive electrode of the transduction unit and a positive electrode of the battery unit and a main negative switch disposed between a negative electrode of the transduction unit and a negative electrode of the battery unit.

3. The energy storage system of claim 2, wherein the battery cell comprises a plurality of battery packs;

the control module further comprises a plurality of slave control units, and each slave control unit is connected with a corresponding battery pack to acquire battery information of the corresponding battery pack.

4. The energy storage system of claim 3, wherein the bus module comprises a plurality of ac switching units, a first end of each of the ac switching units being connected to a bus terminal, a second end of each of the ac switching units being connected to a portion of the energy conversion unit of the energy module.

5. The energy storage system of claim 4, wherein the control module further comprises a master control unit, the master control unit connecting the transduction unit, the master control unit, the slave control unit, and the ac switching unit.

6. The energy storage system of claim 5, wherein the master control unit is configured to:

detecting the state of the alternating current switch unit;

when the alternating current switch unit is closed, a first power-on instruction is sent to the transduction unit so as to enable the transduction unit to be electrified;

and when the energy conversion unit finishes powering up, a second power-up instruction is sent to the main control unit, so that the main control unit controls the energy module to be powered up.

7. The energy storage system of claim 6, wherein the master control unit is configured to perform a self-test prior to detecting the state of the ac switching unit.

8. The energy storage system of claim 6, wherein the master control unit is configured to:

closing the main negative switch when the second power-on instruction is received;

closing the main positive switch when the main negative switch is closed;

and feeding back power-on completion information when the main positive switch is closed.

9. The energy storage system of claim 5, wherein the master control unit is configured to:

when receiving a power-down signal, sending a shutdown instruction to the transduction unit so as to shutdown the transduction unit;

when the energy conversion unit finishes stopping, a power-down instruction is sent to the main control unit, so that the main control unit controls the energy module to power down;

and when the energy module finishes power-down, controlling the alternating current switch unit to be disconnected.

10. The energy storage system of claim 9, wherein the master control unit is configured to:

detecting a current value when the power-down instruction is received;

if the current value is smaller than a set value, the main positive switch is disconnected, and if the current value is larger than the set value, the main positive switch is disconnected in a delay mode;

delay-turning off the main negative switch;

and feeding back power-down completion information after at least one of the main positive switch and the main negative switch is completely disconnected.