High-voltage-class alternating-current energy storage cabin

Abstract

The utility model belongs to the field of battery energy storage systems, and discloses a high-voltage-class alternating-current energy storage cabin, which not only improves the voltage of the battery energy storage system, but also solves the problems of circulating current among battery clusters and'wooden barrel effect '. The energy density, the power density and the energy efficiency of the system are remarkably improved, the energy efficiency is remarkably improved by transversely arranging the battery modules into clusters and applying a string type energy storage converter and a cluster control type design scheme, and the system comprises a plurality of high-voltage-grade battery clusters located in an alternating-current energy storage cabin. The battery cluster comprises five battery modules which are connected in series, and the battery cluster is electrically connected with the direct current side of the string type energy storage converter.

Description

Technical Field

[0001] This utility model belongs to the field of battery energy storage systems, specifically relating to a high-voltage AC energy storage chamber. Background Technology

[0002] The existing 1500V medium-voltage DC energy storage container adopts a centralized integrated approach. The DC-side battery voltage range is 1040V to 1500V. Each battery module consists of 104 cells connected in series. Four battery modules are connected in series to form a battery cluster of 416 cells in parallel. Each battery cluster is connected to a high-voltage box. All battery clusters are then combined into DC power through a distribution combiner cabinet and connected to an external centralized energy storage converter. Finally, the voltage is stepped up by a transformer and connected to the power grid. The energy storage container is a design form of DC energy storage container, including batteries, high-voltage boxes, thermal management components, fire protection components, auxiliary equipment, etc.

[0003] Currently, wind and solar power plants and energy storage systems are developing towards larger capacities and higher power. Existing 1500V medium-voltage DC energy storage modules can only achieve the goal of increasing the system's rated power by increasing the operating current. However, increasing the operating current will significantly increase the battery temperature of the battery energy storage system, making it impossible for the thermal management system to effectively control the battery temperature, posing a significant risk of battery thermal runaway. Furthermore, the existing 1500V medium-voltage DC energy storage modules have relatively low battery system voltages, resulting in low system energy density and power density. Moreover, the battery clusters are DC-side collectors, creating a risk of circulating current between clusters and exhibiting a "weakest link" effect, leading to low system energy efficiency. Utility Model Content

[0004] To address the shortcomings of existing technologies, this invention provides a high-voltage AC energy storage chamber, which not only increases the voltage of the battery energy storage system but also solves the problems of circulating current between battery clusters and the "weakest link" effect. This significantly improves the system's energy density, power density, and energy efficiency.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A high-voltage AC energy storage compartment, electrically connected to an external transformer and connected to an external power grid, is characterized by comprising: multiple high-voltage battery clusters, all located inside the high-voltage AC energy storage compartment, each battery cluster comprising multiple battery modules connected in series, and the battery clusters being electrically connected to the DC side of a string energy storage converter.

[0007] Preferably, the AC side output of multiple string energy storage converters is combined and connected to an external transformer.

[0008] Preferably, the high-voltage AC energy storage compartment has a length direction and a height direction, with multiple battery clusters evenly distributed along the height direction and all battery modules of the same battery cluster distributed along the length direction.

[0009] Furthermore, each battery cluster occupies a corresponding height position in the cabin height direction.

[0010] Preferably, the battery cluster includes five battery modules, each battery module having 104 cells connected in series, each cell having a terminal voltage of 2.5V-3.65V.

[0011] Compared with the prior art, the beneficial effects of this utility model are:

[0012] 1. Because the high-voltage AC energy storage compartment of this utility model includes multiple battery clusters located inside itself, and each battery cluster includes five battery modules connected in series, the five battery modules are clustered laterally, and the battery clusters are electrically connected to the DC side of the string energy storage converter, and the cluster-controlled design scheme, this utility model achieves no inter-cluster circulating current and "barrel effect", thereby significantly improving the energy density, power density and energy efficiency of the system.

[0013] 2. Because the high-voltage battery cluster of this utility model includes five battery modules, each battery module has 104 cells connected in series, and the terminal voltage of each cell is 2.5V-3.65V, that is, the voltage of the battery cluster can reach about 2000V. Therefore, this utility model realizes a 2000V high-voltage AC energy storage chamber, which significantly improves energy density and power density. In addition, the 2000V high-voltage AC energy storage chamber solution can use the battery modules of the traditional 1500V DC energy storage chamber, as well as the corresponding production lines and tooling equipment. Attached Figure Description

[0014] Figure 1 This is a top view schematic diagram of a high-voltage AC energy storage compartment according to an embodiment of the present invention.

[0015] Figure 2 This is a simplified front view schematic diagram of a high-voltage AC energy storage compartment according to an embodiment of the present invention.

[0016] In the diagram: 100, high-voltage AC energy storage compartment; D1, compartment length direction; D2, compartment height direction; 10, battery cluster; 11, battery module; 111, battery cell; 12, string energy storage converter. Detailed Implementation

[0017] To make the technical means, creative features, objectives and effects of this utility model easier to understand, the following embodiments, in conjunction with the accompanying drawings, specifically illustrate the high-voltage AC energy storage chamber of this utility model. It should be noted that the description of these embodiments is for the purpose of helping to understand this utility model, but does not constitute a limitation on this utility model.

[0018] like Figure 1 and Figure 2 As shown, the high-voltage AC energy storage compartment 100 in this embodiment is electrically connected to an external transformer (not shown in the figure). The high-voltage AC energy storage compartment 100 has a length direction D1 and a height direction D2.

[0019] The high-voltage AC energy storage compartment 100 includes multiple battery clusters 10.

[0020] Multiple battery clusters 10 are located inside the high-voltage AC energy storage compartment 100, and the multiple battery clusters 10 are evenly distributed along the height direction D2 of the compartment. Each battery cluster 10 occupies only one height position in the height direction D2 of the compartment. That is, the multiple battery clusters 10 are laterally distributed in the high-voltage AC energy storage compartment 100. In this embodiment, the multiple battery clusters 10 are correspondingly set at different height positions by multiple cluster spacers (not shown in the figure) evenly distributed along the height direction D2 of the compartment in the high-voltage AC energy storage compartment 100.

[0021] The battery cluster 10 includes five battery modules 11 connected in series. The battery cluster 10 is electrically connected to the DC side of the string energy storage converter 12. The AC side output of the multiple string energy storage converters is combined and connected to an external transformer. Specifically, each battery cluster 10 is connected to one string energy storage converter 12. Thus, the AC side of the multiple string energy storage converters 12 can be controlled to achieve output consistency, thereby significantly improving the energy efficiency of the AC energy storage compartment.

[0022] Each battery cluster 10 includes five battery modules 11, each battery module 11 having 104 cells 111 connected in series. The terminal voltage of each cell 111 is 2.5V-3.65V. All battery modules 11 in the same battery cluster 10 are distributed along the length D of the compartment. Specifically, the battery cluster 10 is a parallel 520 series connection of five battery modules 11, with a total terminal voltage of 1300V-1898V, that is, the battery cluster voltage can reach about 2000V.

[0023] The above embodiments are preferred embodiments of this utility model and are not intended to limit the scope of protection of this utility model. Various modifications or variations that can be made by those skilled in the art without creative effort within the scope of the appended claims are still within the scope of protection of this patent.

Claims

1. A high-voltage-grade alternating current energy storage cabin, electrically connected with an external transformer and connected to an external power grid, characterized in that, The high-voltage-level AC energy storage cabin comprises: a plurality of battery clusters, each of which is located inside the high-voltage-level AC energy storage cabin, each battery cluster comprises a plurality of battery modules connected in series with each other, and the battery cluster is electrically connected to the DC side of the group string type energy storage converter, wherein the high-voltage-level AC energy storage cabin has a cabin length direction and a cabin height direction, a plurality of cluster spacing plates are uniformly distributed along the cabin height direction of the high-voltage-level AC energy storage cabin, the plurality of battery clusters are uniformly distributed along the cabin height direction, and all the battery modules of the same battery cluster are distributed along the cabin length direction.

2. The high-voltage-level AC energy storage cabin according to claim 1, wherein: wherein the AC sides of the plurality of group string type energy storage converters are connected in parallel and connected to an external transformer.

3. The high-voltage-level AC energy storage cabin according to claim 1, wherein: wherein each battery cluster occupies a height position corresponding to the cabin height direction.

4. The high-voltage-level AC energy storage cabin according to claim 1, wherein: wherein each battery cluster comprises five battery modules, each of which has 104 battery cells connected in series, and each battery cell has an end voltage of 2.5V-3.65V.

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