AC / DC fusion energy storage battery system

Abstract

The utility model discloses an alternating current and direct current fusion energy storage battery system which comprises a battery cabin internally provided with a battery area, a PCS area, a confluence area and a liquid cooling machine area which are mutually isolated, a plurality of battery clusters are installed in the battery area, a plurality of fusion energy storage converters are installed in the PCS area, and each battery cluster is connected with the fusion energy storage converter; the fusion energy storage converter comprises an isolating switch, a fuse, a direct current filter, a direct current contactor, a converter module, an alternating current filter, an alternating current contactor and an alternating current lightning protection device; a liquid cooling unit is mounted in the liquid cooling machine area, and a cooling assembly of the battery group is connected with the liquid cooling unit through a liquid cooling pipe; a primary confluence device, a related communication control device, an auxiliary device and a power distribution device are installed in the confluence area. The battery clusters are converted into alternating current through the PCS, the alternating current output circuits are connected in parallel and then lead out, the problem of inter-cluster circulating current does not exist in front of the battery clusters, the influence on the batteries is greatly reduced, and the service life of the batteries can be prolonged.

Description

Technical Field

[0001] The utility model relates to the technical field of energy storage devices, and more specifically, to an AC-DC integrated energy storage battery system. Background Art

[0002] Battery energy storage technology has been continuously promoted and improved under the background of carbon peaking and carbon neutrality, and has become a key supporting device for clean power generation technologies such as photovoltaic and wind power. It has been widely used in fields such as power grid peak shaving and frequency modulation, and user-side energy storage.

[0003] Traditional energy storage battery cabins generally adopt a scheme where one cluster corresponds to one high-voltage box, multiple battery clusters are converged on the DC side, and finally the outgoing line is connected to the PCS outside the cabin. This scheme has the following problems:

[0004] First, multiple battery clusters are converged on the DC side. Since the voltages of each battery cluster are not exactly the same, inter-cluster circulating current occurs, and the core cells face different working conditions, resulting in a further increase in the consistency difference of the core cells, affecting the overall system life; the PCS and the battery cabin are arranged separately, resulting in an increase in land use costs; the system flexibility is insufficient, and any cluster failure will cause the entire battery cabin system to shut down.

[0005] Second, there is a problem of partial functional overlap of electrical components between the PCS and the high-voltage box, resulting in some cost waste.

[0006] Third, when integrating the PCS into the battery cabin, the heat dissipation problem of the PCS needs to be considered to prevent the PCS from overheating.

[0007] Finally, when integrating the PCS into the battery cabin, the fire protection and safety problems of the PCS need to be considered to avoid the impact of PCS fire on the battery.

[0008] As Figure 1 shown, multiple battery clusters of a conventional centralized energy storage system are respectively connected in parallel through high-voltage boxes and then connected to the PCS. This will lead to the occurrence of inter-cluster circulating current. Because of the inconsistency of the core cells in each cluster, the voltages of each core cell are different, so the total voltages of each battery cluster will also be different. When each battery cluster is connected in parallel, circulating current will be generated. The current flowing through the core cells within a single battery cluster is the same, but when several battery clusters are connected in parallel, the currents of each cluster are not the same, which will lead to inconsistency of the core cells between clusters. One of the reasons for the inconsistency of the currents of each cluster is the inter-cluster circulating current, and the circulating current further causes the inconsistency of the currents of each cluster, and the inconsistency of the core cells is further increased, thus resulting in a vicious cycle. Summary of the Utility Model

[0009] To solve the above technical problems, the utility model provides an AC-DC integrated energy storage battery system.

[0010] The technical solution of the utility model is as follows:

[0011] An AC-DC integrated energy storage battery system,

[0012] including a battery cabin with mutually isolated battery area 1, PCS area 2, busbar area 3 and liquid chiller area 4 inside,

[0013] a number of battery clusters are installed in the battery area, and a number of integrated energy storage converters are installed in the PCS area,

[0014] each battery cluster is respectively connected to the integrated energy storage converter;

[0015] the integrated energy storage converter includes a disconnect switch, a fuse, a DC filter, a DC contactor, a conversion module, an AC filter, an AC contactor, an AC lightning arrester;

[0016] the battery cluster, disconnect switch, fuse, DC filter, DC contactor, conversion module, AC filter, AC contactor are electrically connected in sequence;

[0017] the AC lightning arrester is arranged on the AC output circuit of the AC contactor;

[0018] a liquid chiller unit is installed in the liquid chiller area, and the cooling components of the battery pack are connected to the liquid chiller unit through liquid cooling pipes;

[0019] a primary busbar equipment and related communication control equipment, auxiliary equipment and power distribution equipment are installed in the busbar area.

[0020] Among them, a current acquisition device is installed on the integrated energy storage converter, and a pre-charge circuit is installed in parallel with the DC contactor.

[0021] Among them, a circuit breaker is installed on the AC output circuit of each integrated energy storage converter.

[0022] Among them, the number of the integrated energy storage converters is an even number, distributed in two columns, symmetrically installed in the PCS area, and an air-cooling channel is arranged below the PCS area.

[0023] Among them, the air-cooling channel is arranged below the integrated energy storage converter, an air inlet is opened on the front side of the air-cooling channel, an air outlet is opened at the bottom of the air-cooling channel, and an air-cooling machine is arranged inside the integrated energy storage converter.

[0024] Among them, it further includes a battery management system, and the battery management system is connected to the conversion module for controlling the conversion module of the integrated energy storage converter.

[0025] Among them, the battery management system includes a slave control module, a master control module, and a general control module. The slave control module is placed inside the battery pack of the battery cluster and is connected to the master control module. The master control module is placed and connected to the converters module of the integrated energy storage converter. The general control module is installed in the busbar area and is connected to each master control module for communicating with various devices in the battery compartment.

[0026] Among them, a dehumidifier is installed in the battery area.

[0027] Among them, a fire protection component is further included. The fire protection component includes an exhaust fan, a fire control box, a fire gas tank, and a fire pipeline.

[0028] Among them, two power distribution circuits are also provided. One is a conventional 380V to supply power to the liquid cooling unit and the dehumidifier, and the other is from 220V through an uninterruptible power supply (UPS) to supply power to the fire protection component and the battery management system. The uninterruptible power supply (UPS) has a backup power of 2 hours, realizing dual power supply for important loads and still being able to operate for 2 hours after power failure.

[0029] Compared with the prior art, an AC-DC integrated energy storage battery system provided by the present utility model includes a battery compartment with mutually isolated battery area, PCS area, busbar area, and liquid cooling unit area. A number of battery clusters are installed in the battery area, and a number of integrated energy storage converters are installed in the PCS area. Each battery cluster is respectively connected to the integrated energy storage converter; the integrated energy storage converter includes a disconnect switch, a fuse + current acquisition, a DC filter, a DC contactor, a converters module, an AC filter, an AC contactor, and an AC lightning arrester; the battery cluster, the disconnect switch, the fuse + current acquisition, the DC filter, the DC contactor + precharge circuit, the converters module, the AC filter, and the AC contactor are electrically connected in sequence; the AC lightning arrester is arranged on the AC output circuit of the AC contactor; a liquid cooling unit is installed in the liquid cooling unit area, and the cooling component of the battery cluster is connected to the liquid cooling unit through a liquid cooling pipe; a primary busbar device and related communication control devices, auxiliary devices, and power distribution devices are installed in the busbar area.

[0030] The present utility model redesigns the overall structure and air duct of the energy storage converter. The energy storage converter integrates the high-voltage box component. The battery clusters are respectively connected in series with the integrated energy storage converter and the circuit breaker of the integrated high-voltage box component. The AC output circuits after series connection are connected in parallel and then lead out. There is no inter-cluster circulating current problem among the battery clusters, which greatly reduces the impact on the battery and can extend the battery life. At the same time, one battery cluster corresponds to one integrated energy storage converter. From the perspective of the system level, one battery cluster can be regarded as an independent industrial and commercial energy storage battery system. Each cluster is independent and does not affect each other, and the flexibility of the overall system is greatly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0032] Figure 1 It is an electrical diagram of the prior art PCS;

[0033] Figure 2 It is an electrical diagram of the present invention integrating an energy storage converter;

[0034] Figure 3 It is a top view inside the AC-DC integrated energy storage battery system of the present invention;

[0035] Figure 4 It is a front view of the AC-DC integrated energy storage battery system of the present invention;

[0036] In the figure, there are battery area 1, PCS area 2, busbar area 3, liquid chiller area 4, battery compartment 5, battery cluster 11, integrated energy storage converter 21, dehumidifier 12, exhaust fan 13, fire control box 14, and fire gas cylinder 15. Detailed implementation manners

[0037] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0038] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly disposed on the other element; when an element is referred to as "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0039] It should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation of the present invention.

[0040] In addition, the terms "first" and "second" are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, the meanings of "a plurality of" and "several" are two or more, unless otherwise specifically defined.

[0041] It should be noted that the structures, ratios, sizes, etc. shown in the drawings of this specification are only used to cooperate with the content disclosed in the specification for those skilled in the art to understand and read, and are not used to limit the implementable conditions of the present utility model. Therefore, they do not have substantial technical significance. Any modification of the structure, change of the proportional relationship, or adjustment of the size, without affecting the efficacy that the present utility model can produce and the purpose that can be achieved, should still fall within the scope covered by the technical content disclosed in the present utility model.

[0042] The embodiments of the present utility model are written in a progressive manner.

[0043] An AC-DC integrated energy storage battery system

[0044] comprises a battery cabin 5 with internally provided and mutually isolated battery area 11, PCS area 22, busbar area 33 and liquid chiller area 44

[0045] A number of battery clusters 11 are installed in the battery area 1, and a number of integrated energy storage converters 21 are installed in the PCS area 2

[0046] Each battery cluster 11 is respectively connected to the integrated energy storage converter 21

[0047] The integrated energy storage converter 21 includes a disconnector, a fuse, a DC filter, a DC contactor, a conversion module, an AC filter, an AC contactor, and an AC lightning arrester

[0048] The battery cluster 11, disconnector, fuse + current acquisition, DC filter, DC contactor + precharge circuit, conversion module, AC filter, and AC contactor are electrically connected in sequence

[0049] The AC lightning arrester is arranged on the AC output circuit of the AC contactor

[0050] A liquid chiller unit is installed in the liquid chiller area 4, and the cooling components of the battery cluster are connected to the liquid chiller unit through liquid cooling pipes

[0051] Primary busbar equipment and related communication control equipment, auxiliary equipment and power distribution equipment are installed in the busbar area 3

[0052] The battery cluster 11 of the present utility model is respectively connected in series with the integrated energy storage inverter 21 and the circuit breaker of the integrated high-voltage box assembly. The AC output circuits after being connected in series are connected in parallel and then lead out. There is no problem of inter-cluster circulating current before the battery cluster 11, which greatly reduces the impact on the battery and can extend the battery life.

[0053] Combined with Figure 2 From the electrical diagram of the integrated energy storage inverter 21 of the present utility model, it can be seen that compared with the energy storage system in the prior art, all electrical components in the high-voltage box except the battery management system can be removed in the present utility model, including disconnectors, DC contactors, fuses, lightning arresters, current acquisition devices, etc. Moreover, compared with the energy storage system in the prior art, the integrated energy storage inverter 21 integrating the function of the high-voltage box has a high integration degree, and directly saves the land cost of the original energy storage inverter.

[0054] Four battery packs of the present utility model form a battery cluster 11. n battery clusters 11 are respectively connected in AC at the busbar area 3 through n integrated energy storage inverters 21. The busbar area 3 is also equipped with communication control equipment, auxiliary equipment, distribution equipment, etc., including switches, local controllers, circuit breakers, surge protection devices, and UPS (uninterruptible power supply), etc. The local controller is responsible for the communication and control between the n integrated energy storage inverters 21 in the battery compartment 5 and other control devices. The local controller can be regarded as a large integrated energy storage inverter 21 integrating n small integrated energy storage inverters 21.

[0055] A current acquisition device is installed on the integrated energy storage inverter 21 of the present utility model, and a pre-charge circuit is installed in parallel with the DC contactor.

[0056] A circuit breaker is installed on the AC output circuit of each integrated energy storage inverter 21 of the present utility model to protect the circuit.

[0057] The number of the integrated energy storage inverters 21 of the present utility model is an even number, distributed in two columns, symmetrically installed in the PCS area 2. The two columns of integrated energy storage inverters 21 of the present utility model are back-to-back. An air-cooling channel is arranged below the PCS area 2. Cold air passes through the air-cooling channel to cool the integrated energy storage inverter 21. The integrated energy storage inverter 21 of the present utility model adopts the air-cooling method, and the battery cluster 11 adopts the liquid-cooling method, so that the temperatures of the battery area 1 and the PCS area 2 can be independently controlled, and the problem that the safe operating temperature ranges of the battery cluster 11 and the integrated energy storage inverter 21 are different can be solved.

[0058] The air-cooling channel of the present utility model is arranged below the integrated energy storage inverter 21. An air inlet is opened on the front side of the air-cooling channel, and an air outlet is opened at the bottom of the air-cooling channel. An air-cooling machine is arranged inside the integrated energy storage inverter (21).

[0059] The present utility model further includes a battery management system, which is connected to the converter module and is used to control the converter module of the integrated energy storage converter 21 and control the working states and communications of various electrical components of the integrated energy storage converter 21.

[0060] The battery management system of the present utility model includes a slave control module, a master control module and a general control module. The slave control module is placed inside the battery pack of the battery cluster 11 and is used to detect the cluster voltage and cluster current data, collect data such as the cell temperature and voltage, and is connected to the master control module. The master control module is placed where the integrated energy storage converter 21 is connected to the converter module, collects the cluster voltage and cluster current and judges the states of the electrical components, and plays a role in protecting the circuit by controlling the on-off of the contactor inside the integrated energy storage converter 21. The general control module is installed in the busbar area 3 and is connected to each master control module and is used to communicate with each device in the battery compartment 5, mainly responsible for communicating with the auxiliary devices inside the compartment, including equipment such as the liquid cooling unit, the dehumidifier 12 and the local controller, receives signals such as the water immersion probe and the fire alarm, and is responsible for realizing the unified external communication function of the battery management system. The battery management system's slave control module - master control module - general control module realizes the hierarchical management and control strategy inside the battery compartment 5 through communication. The water immersion probe can be arranged at the bottom of the compartment. When the battery compartment 5 is flooded, an alarm will be issued, which is connected to the general control through a dry contact and then an alarm is issued through the fire alarm.

[0061] A dehumidifier 12 is installed inside the battery area 1 of the present utility model, and it can be installed on the front cabin door to ensure that the humidity inside the compartment meets the operation standard.

[0062] The present utility model further includes a fire protection component, which includes an exhaust fan 13, a fire control box 14, a fire gas tank 15 and a fire pipeline, and the fire extinguishing agent stored in the fire gas tank 15 is sprayed to the fire location through the fire pipeline.

[0063] The fire protection component of the present utility model can be installed outside the battery compartment 5. The exhaust fan 13 is used to discharge the combustible gas inside the compartment. The fire control system of the fire control box 14 is used for fire logic judgment and control. The fire gas tank 15 is used to store perfluorohexanone. The fire control system adopts 2 sets of independent protection logics, namely compartment-level detection and compartment-level spraying, and package-level detection and cluster-level spraying. It judges whether a fire occurs through temperature sensor detection, smoke sensor detection and other combustible gas detections. There are three levels of alarms corresponding to different detection values, and different actions are taken respectively. The fire extinguishing methods adopt two methods of spraying perfluorohexanone and water spray. The integrated energy storage converter 21 is internally provided with aerosol. When a fire occurs inside the integrated energy storage converter 21, the integrated energy storage converter 21 is directly extinguished without passing through the fire control system, and the PCS area 2 and the battery area 1 are isolated by fireproof materials to block the spread of the fire in the integrated energy storage converter 21 to the battery area 1. The integrated energy storage converter 21 is internally provided with fire protection, which can effectively ensure the safety of the battery area 1.

[0064] For power supply installation, the utility model is also provided with two distribution circuits. One is a conventional 380V circuit to supply power to the liquid cooling unit and the dehumidifier 12, and the other is a circuit that supplies power to the fire protection components and the battery management system from 220V through an uninterruptible power supply (UPS). The UPS has a backup power supply for 2 hours, realizing dual power supply for important loads and enabling operation for 2 hours after power failure.

[0065] The above description of the disclosed embodiments enables those skilled in the art to implement or use the utility model. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the utility model. Therefore, the utility model will not be limited to the embodiments shown herein, but rather will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An AC / DC fusion energy storage battery system, characterized in that: A battery compartment (5) is provided with a battery area (1), a PCS area (2), a confluence area (3) and a liquid cooling machine area (4) which are isolated from each other. The battery area (1) is equipped with a plurality of battery clusters (11), and the PCS area (2) is equipped with a plurality of fusion energy storage converters (21). Each battery cluster (11) is respectively connected to a fusion energy storage converter (21); The fusion energy storage converter (21) comprises an isolating switch, a fuse, a DC filter, a DC contactor, a converter module, an AC filter, an AC contactor, and an AC lightning arrester; The battery cluster (11), isolating switch, fuse, DC filter, DC contactor, converter module, AC filter, and AC contactor are electrically connected in sequence; The AC lightning arrester is arranged on the AC output circuit of the AC contactor; A liquid cooling unit is installed in the liquid cooling unit area (4), and the cooling components of the battery group are connected to the liquid cooling unit via a liquid cooling pipe; The merging area (3) is equipped with primary merging equipment and related communication control equipment, auxiliary equipment and power distribution equipment.

2. The AC / DC fusion energy storage battery system according to claim 1, characterized in that: A current collection device is installed on the fusion energy storage converter (21), and a pre-charging circuit is installed in parallel with the DC contactor.

3. The AC / DC fusion energy storage battery system according to claim 1, characterized in that: A circuit breaker is installed on the AC output circuit of each fusion energy storage converter (21).

4. The AC / DC fusion energy storage battery system according to claim 1, characterized in that: The number of the fusion energy storage converters (21) is an even number, distributed in two rows, and symmetrically installed in the PCS area (2), and an air cooling channel is provided below the PCS area (2).

5. The AC / DC fusion energy storage battery system according to claim 4, characterized in that: The air cooling channel is arranged below the fusion energy storage converter (21), an air inlet is provided at the front side of the air cooling channel, an air outlet is provided at the bottom of the air cooling channel, and an air cooler is provided inside the fusion energy storage converter (21).

6. The AC / DC fusion energy storage battery system according to claim 1, characterized in that: It also includes a battery management system, which is connected to the conversion module and is used to control the conversion module of the fusion energy storage converter (21).

7. The AC / DC fusion energy storage battery system according to claim 1, characterized in that: The battery management system comprises a slave control module, a master control module and a master control module. The slave control module is placed in a battery pack of a battery cluster (11) and is connected to the master control module. The master control module is placed in a fusion energy storage converter (21) and is connected to the converter module. The master control module is installed in a confluence area (3) and is connected to each master control module for communicating with each device in a battery compartment (5).

8. The AC / DC fusion energy storage battery system according to claim 1, characterized in that: A dehumidifier (12) is installed in the battery area (1).

9. The AC / DC fusion energy storage battery system according to claim 1, characterized in that: It also includes a fire-fighting assembly, which includes an exhaust fan (13), a fire-fighting control box (14), a fire-fighting gas tank (15), and a fire-fighting pipeline.

10. The AC / DC fusion energy storage battery system according to claim 1, characterized in that: Two power distribution circuits are also provided, one of which is a conventional 380V circuit that supplies power to the liquid cooling unit and the dehumidifier (12), and the other is a 220V circuit that supplies power to the fire protection components and the battery management system via an uninterruptible power supply UPS.

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