Optical storage grid-connected integrated energy storage system

Abstract

The invention discloses a light-storage grid-connected integrated energy storage system, and relates to the technical field of energy storage equipment. The box body is transversely divided into a power conversion area, a control management area, an energy storage battery area and an auxiliary equipment area through an isolation plate, the power conversion area is further divided into two areas through the isolation plate, an isolation transformer and a grid-connected switch cabinet are arranged in the outermost area of the power conversion area, an energy storage converter is arranged in the inner area of the power conversion area, and the grid-connected switch cabinet is arranged in the outer area of the power conversion area. An EMS management module and a confluence cabinet are arranged in the control management area in parallel, a lithium battery pack is arranged in the energy storage battery area, and the power conversion area, the control management area, the energy storage battery area and the auxiliary equipment area are scientifically partitioned and integrated in a standard 20-foot container by adopting a modular plane layout design. The space utilization rate and the equipment installation density are greatly improved, and the transportation cost is reduced.

Description

Technical Field

[0001] The present invention relates to a photovoltaic-storage-grid-connected integrated energy storage system, and relates to the technical field of energy storage equipment. Background Art

[0002] With the increasing penetration of renewable energy, the conflict between the intermittent nature of photovoltaic power generation and the need for grid stability is becoming increasingly prominent. Grid-connected photovoltaic and energy storage systems, which use energy storage units to smooth power fluctuations, have become a key technical approach to addressing this issue. Existing technologies primarily integrate photovoltaic power generation, energy storage units, and the grid using a decentralized deployment model, whereby photovoltaic inverters, energy storage batteries, PCS converters, grid-connected cabinets, and EMS microgrid management systems are installed independently and connected at the site level via cables.

[0003] The existing distributed deployment model has wide spacing between devices, making thermal runaway less likely to occur. However, due to the adoption of a distributed deployment model, the overall footprint is large, deployment is more troublesome, and the land cost is high. In addition, the overall size of each device is large, making transportation inconvenient. When transporting to the site, temporary installation and debugging are required, which requires a high level of professionalism from the operators. Therefore, a photovoltaic and grid-connected integrated energy storage system is proposed to solve the problems existing in the existing technology. Summary of the Invention

[0004] The purpose of the present invention is to address the defects or shortcomings in the existing technology and provide an integrated photovoltaic and grid-connected energy storage system. By adopting a modular planar layout design, the power conversion area, control and management area, energy storage battery area and auxiliary equipment area are scientifically divided and integrated in a standard 20-foot container, greatly improving space utilization and equipment installation density, and reducing transportation costs.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: it includes a box body 1, which is laterally divided by an isolation plate 14 to form a power conversion area a, a control and management area b, an energy storage battery area c and an auxiliary equipment area d. The power conversion area a is further divided into two areas by the isolation plate 14. The outermost area of the power conversion area a is provided with an isolation transformer 7 and a grid-connected switch cabinet 9, and the inner area of the power conversion area a is provided with an energy storage converter 6. The control and management area b is provided with an EMS management module 4 and a combiner cabinet 3 in parallel, and the energy storage battery area c is provided with a lithium battery pack 2.

[0006] Furthermore, a liquid cooling unit 10 is provided in the auxiliary equipment area d, and the liquid cooling unit 10 is connected to the lithium battery pack 2. The liquid cooling unit 10 includes a liquid cooling host and a liquid distributor, and the liquid cooling host and the liquid distributor are connected through a pipeline.

[0007] Furthermore, a station transformer 8 is provided on one side of the grid-connected switch cabinet 9, and the two are directly connected through a copper busbar in a back-to-back installation layout. The isolation transformer 7 and the energy storage converter 6 are also directly connected through a copper busbar in a back-to-back installation layout. The station transformer 8 is also electrically connected to the junction cabinet 3.

[0008] Furthermore, the lithium battery pack 2 is electrically connected to the junction box 3 and the energy storage converter 6, the junction box 3 is electrically connected to the energy storage converter 6, the energy storage converter 6 is electrically connected to the isolation transformer 7, and the isolation transformer 7 is electrically connected to the grid-connected switch cabinet 9.

[0009] Furthermore, the energy storage converter 6 is also provided with a photovoltaic input port.

[0010] Furthermore, the EMS management module 4 is respectively connected to the lithium battery pack 2, the junction box 3, the energy storage converter 6, the isolation transformer 7, the station transformer 8, and the grid-connected switch cabinet 9, and the EMS management module 4 is integrated with a wireless transmission module for wireless connection with the terminal control system.

[0011] Furthermore, a fire control cabinet 5 is provided in the control and management area b and is connected to the EMS management module 4 through hard wiring, and the fire control cabinet 5 is electrically connected to the junction cabinet 3.

[0012] Furthermore, the energy storage battery area c adopts a layered drawer structure, and the lithium battery pack 2 adopts a multi-layer PACK structure and is arranged in the drawer structure. At the same time, a liquid cooling plate is provided at the bottom of each layer of PACK, which is connected to the liquid cooling pipeline through a quick connector and then connected to the liquid distributor.

[0013] Furthermore, the front side of the box body 1 is provided with a plurality of sealed doors 11 corresponding to the power conversion area a, the control management area b, the energy storage battery area c and the auxiliary equipment area d.

[0014] Furthermore, the bottom of the box body 1 is provided with a raised moisture-proof layer 12 .

[0015] After adopting the above technical solution, the beneficial effects of the present invention are: by adopting a modular plane layout design, the power conversion area, control management area, energy storage battery area and auxiliary equipment area are scientifically divided and integrated in a standard 20-foot container, which greatly improves space utilization and equipment installation density, and reduces transportation costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0017] Figure 1 It is a structural schematic diagram of the present invention;

[0018] Figure 2 It is a top view of the internal structure of the present invention;

[0019] Figure 3 yes Figure 2 A second angle view of

[0020] Figure 4 yes Figure 2 A third angle view of;

[0021] Figure 5 It is a schematic diagram of the assembly effect of the lithium battery pack 2 in the present invention.

[0022] Explanation of the accompanying symbols: cabinet 1, lithium battery pack 2, junction box 3, EMS management module 4, fire control cabinet 5, energy storage converter 6, isolation transformer 7, station transformer 8, grid-connected switch cabinet 9, liquid cooling unit 10, sealed compartment door 11, raised moisture-proof layer 12, power conversion area a, control and management area b, energy storage battery area c and auxiliary equipment area d. DETAILED DESCRIPTION

[0023] See Figure 1-Figure 5As shown, the technical solution adopted in this specific embodiment is: it includes a box body 1, which is horizontally divided by an isolation plate 14 to form a power conversion area a, a control management area b, an energy storage battery area c and an auxiliary equipment area d. The power conversion area a is further divided into two areas by the isolation plate 14. An isolation transformer 7 and a grid-connected switch cabinet 9 are arranged in the outermost area of the power conversion area a, and an energy storage converter 6 is arranged in the inner area of the power conversion area a. An EMS management module 4 and a junction cabinet 3 are arranged in parallel in the control management area b. A lithium battery pack 2 is arranged in the energy storage battery area c. A station transformer 8 is also arranged on one side of the grid-connected switch cabinet 9, and the two are directly connected by a copper busbar in a back-to-back installation layout. The isolation transformer 7 and the energy storage converter 6 are also arranged in a back-to-back manner. The installation layout is directly connected through copper bars, and the station transformer 8 is also electrically connected to the combiner cabinet 3. Traditional energy storage output systems usually require the layout of multiple sets of equipment in a large area, which not only occupies a large area but is also inconvenient to transport. At the same time, professional personnel are required to install and debug the equipment after it arrives on site. Therefore, in this embodiment, an integrated photovoltaic storage grid-connected device is used. The box is separated into several cavities by isolation panels, and the lithium battery pack, combiner cabinet, EMS management module, fire control cabinet, energy storage converter, isolation transformer, station transformer, and grid-connected switch cabinet are arranged in the corresponding cavities according to their functions. At the same time, the equipment is installed in a back-to-back layout with a spacing of ≤250mm, which can effectively improve space utilization, reduce cable length, and reduce assembly difficulty.

[0024] More specifically, inside the box, the lithium battery pack 2 is electrically connected to the junction box 3 and the energy storage converter 6, the junction box 3 is electrically connected to the energy storage converter 6, the energy storage converter 6 is electrically connected to the isolation transformer 7, the isolation transformer 7 is electrically connected to the grid-connected switch cabinet 9, and the connection direction of the line matches the plane layout of the equipment. The overall working state of the equipment is mainly divided into two categories, one is when the external power supply is normal, and the other is when the external power supply is abnormal. It is understandable that a photovoltaic component is also connected to the outside to power the integrated system. During operation, photovoltaic power is output to the energy storage converter and branched out in the energy storage converter. One path is output to the lithium battery pack for charging, and the other path is output to the isolation transformer for voltage conversion and electrical isolation. The integrated power finally enters the grid-connected switch cabinet to be sent out for use. When the external power input is abnormal, it will switch to the lithium battery pack power supply mode. The lithium battery pack outputs DC power to the junction box, which is then centrally output to the energy storage converter for DC / AC conversion. The converted AC power is then transmitted to the isolation transformer for voltage conversion and electrical isolation. The integrated power finally enters the grid-connected switch cabinet for external use. The dual-mode switching ensures stable power output. In this embodiment, the station transformer is a step-down device, the input end of which is electrically connected to an AC output end of the energy storage converter, and the output end is electrically connected to the junction box. It can be understood that the junction box is not only a multi-input aggregation output part, but also has a distribution output end, which receives the power output by the station transformer, thereby outputting the stepped-down power to the auxiliary equipment. In summary, the power path of the main circuit in this embodiment is isolation transformer → grid-connected switch cabinet → power grid, and the auxiliary circuit path is the AC side of the energy storage converter → station transformer → power distribution part of the junction box → auxiliary equipment.

[0025] In addition, in this embodiment, the bottom of the box 1 is a raised moisture-proof layer 12. Taking a 20-foot container as an example, the height of the raised moisture-proof layer is greater than or equal to 200 mm. The internal integrated cable channel allows the equipment lines to be arranged in it, optimizing the line direction. At the same time, the raised layer is conducive to moisture-proofing, making it suitable for harsh environment application scenarios such as offshore photovoltaic supporting facilities and island microgrids.

[0026] More specifically, the auxiliary equipment area d is provided with a liquid cooling unit 10, which is connected to the lithium battery pack 2. The liquid cooling unit 10 includes a liquid cooling host and a liquid dispenser, and the liquid cooling host and the liquid dispenser are connected by a pipeline. In this embodiment, the energy storage battery area c adopts a layered drawer structure, and each layer is provided with a guide rail structure. The lithium battery pack 2 adopts a multi-layer PACK structure and is arranged in the drawer structure. It is more convenient to move on the guide rail, and it can be understood that the guide rail is provided with a self-locking structure to facilitate locking after the PACK is loaded to prevent movement. At the same time, each layer P A liquid cooling plate is provided at the bottom of the ACK, which is connected to the liquid cooling pipeline through a quick connector and then connected to the liquid distributor. The pull-out drawer structure facilitates the disassembly of each PACK and the connection and installation of the liquid cooling pipeline, so that the liquid cooling unit can control the temperature of the lithium battery pack. It is understandable that a temperature sensor is provided on the lithium battery pack to cooperate with the liquid cooling unit. The liquid cooling host has a built-in flow control valve, which dynamically adjusts the flow rate according to the battery temperature feedback from the BMS: when T>30℃, the flow rate increases to 30L / min; when T<24℃, the heating cycle is started, thereby realizing real-time temperature monitoring.

[0027] To be more specific, the energy storage converter 6 is also provided with a photovoltaic input port, which is a universal structural setting that allows the device to use light energy for output in places where light energy is sufficient, thereby reducing energy consumption.

[0028] To be more specific, the EMS management module 4 is respectively connected to the lithium battery pack 2, the junction box 3, the energy storage converter 6, the isolation transformer 7, the station transformer 8, and the grid-connected switch cabinet 9, and the EMS management module 4 is integrated with a wireless transmission module to wirelessly connect with the terminal control system. In this embodiment, the EMS management module monitors and manages each module, thereby enabling intelligent charging and discharging management, and uploading the monitoring data through the wireless transmission module so that the control center can monitor the operation of the equipment in real time.

[0029] More specifically, a fire control cabinet 5 is provided in the control and management area b, which is connected to the EMS management module 4 through hard wiring, and the fire control cabinet 5 is electrically connected to the junction cabinet 3. The fire control cabinet cooperates with the temperature control of the liquid cooling unit to quickly carry out fire extinguishing control when a fault occurs and thermal runaway occurs. In addition, in this embodiment, the use of perfluorohexanone fire extinguishing agent in the fire control cabinet is safer and more efficient.

[0030] To be more specific, the front side of the box body 1 is provided with multiple sealed doors 11 corresponding to the power conversion area a, the control management area b, the energy storage battery area c and the auxiliary equipment area d. The hinged sealed doors are opened and closed by locks to facilitate equipment maintenance. In one embodiment, the sealed doors are provided with quick-release panels and manholes, which can carry out targeted and rapid maintenance of key equipment.

[0031] The working principle of the present invention is as follows: when the equipment is working, the lithium battery pack 2 outputs DC power to the junction box 3, and the centralized output is sent to the energy storage converter 6 for DC / AC conversion. This is the working state when the external power input is abnormal. When the external power input is normal, the photovoltaic module outputs to the energy storage converter 6 and is divided into two paths. One path is sent to the lithium battery pack 2 for charging, and the other path is sent to the energy storage converter 6 for DC / AC conversion. The converted AC power is sent to the isolation transformer 7 for voltage conversion and electrical isolation. The adjusted power finally enters the grid-connected switch cabinet 9 for external use. During this process, the EMS management module 4 monitors the status of the lithium battery pack 2 and the energy storage converter throughout the process. 6 operating parameters and grid conditions, coordinates and controls the charging and discharging process, and uploads data through the wireless transmission module. When the external photovoltaic input is abnormal, it switches to the output state of the lithium battery pack 2 to ensure continuous normal output. The liquid cooling unit 10 accurately controls the temperature of the lithium battery pack 2 according to the temperature monitoring data throughout the process. If thermal runaway occurs in the lithium battery pack 2, the EMS management module 4 will feedback the monitoring data to the fire control cabinet 5, and the fire control cabinet 5 will trigger the fire extinguishing system to extinguish the fire. Each subsystem forms an organic whole through electrical connections and communication networks to realize the storage, conversion and grid-connected transmission of electric energy, thereby improving space utilization and equipment installation density.

[0032] The above description is only used to illustrate the technical solution of the present invention and is not intended to limit it. Other modifications or equivalent substitutions made to the technical solution of the present invention by ordinary technicians in this field should be included in the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solution of the present invention.

Claims

1. A photovoltaic and grid-connected integrated energy storage system, comprising a housing (1), characterized in that: The box (1) is laterally divided by an isolation plate (14) into a power conversion area (a), a control and management area (b), an energy storage battery area (c), and an auxiliary equipment area (d). The power conversion area (a) is further divided into two areas by the isolation plate (14). An isolation transformer (7) and a grid-connected switch cabinet (9) are arranged in the outermost area of the power conversion area (a). An energy storage converter (6) is arranged in the inner area of the power conversion area (a). An EMS management module (4) and a junction box (3) are arranged in parallel in the control and management area (b). A lithium battery pack (2) is arranged in the energy storage battery area (c).

2. The photovoltaic and grid-connected integrated energy storage system according to claim 1, characterized in that: A liquid cooling unit (10) is provided in the auxiliary equipment area (d), and the liquid cooling unit (10) is connected to the lithium battery pack (2). The liquid cooling unit (10) includes a liquid cooling host and a liquid distributor, and the liquid cooling host and the liquid distributor are connected through a pipeline.

3. The photovoltaic and grid-connected integrated energy storage system according to claim 1, characterized in that: A station transformer (8) is also provided on one side of the grid-connected switch cabinet (9), and the two are directly connected via a copper busbar in a back-to-back installation layout. The isolation transformer (7) and the energy storage converter (6) are also directly connected via a copper busbar in a back-to-back installation layout. The station transformer (8) is also electrically connected to the junction cabinet (3).

4. The photovoltaic and grid-connected integrated energy storage system according to claim 1, characterized in that: The lithium battery pack (2) is electrically connected to the junction box (3) and the energy storage converter (6), the junction box (3) is electrically connected to the energy storage converter (6), the energy storage converter (6) is electrically connected to the isolation transformer (7), and the isolation transformer (7) is electrically connected to the grid-connected switch cabinet (9).

5. The photovoltaic and grid-connected integrated energy storage system according to claim 1, characterized in that: The energy storage converter (6) is also provided with a photovoltaic input port.

6. The photovoltaic and grid-connected integrated energy storage system according to claim 1, characterized in that: The EMS management module (4) is respectively connected to the lithium battery pack (2), the junction box (3), the energy storage converter (6), the isolation transformer (7), the station transformer (8), and the grid-connected switch cabinet (9), and the EMS management module (4) is integrated with a wireless transmission module for wireless connection with the terminal control system.

7. The photovoltaic and grid-connected integrated energy storage system according to claim 1, characterized in that: The control and management area (b) is also provided with a fire control cabinet (5) which is connected to the EMS management module (4) through hard wiring, and the fire control cabinet (5) is electrically connected to the junction cabinet (3).

8. The photovoltaic-storage-grid-connected integrated energy storage system according to claim 1, characterized in that: The energy storage battery area (c) adopts a layered drawer structure, and the lithium battery pack (2) adopts a multi-layer PACK structure and is arranged in the drawer structure. At the same time, a liquid cooling plate is provided at the bottom of each layer of PACK and is connected to the liquid cooling pipeline through a quick connector and then connected to the liquid distributor.

9. The photovoltaic-storage-grid-connected integrated energy storage system according to claim 1, characterized in that: The front side of the box body (1) is provided with a plurality of sealed doors (11) corresponding to the power conversion area (a), the control management area (b), the energy storage battery area (c) and the auxiliary equipment area (d).

10. The photovoltaic and grid-connected integrated energy storage system according to claim 1, characterized in that: The bottom of the box body (1) is a raised moisture-proof layer (12).

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