A liquid-cooled industrial and commercial energy storage integrated machine and industrial and commercial system

Abstract

The utility model discloses a liquid-cooled industrial and commercial energy storage integrated machine and a liquid-cooled industrial and commercial system, including two identical sub-energy storage systems, each of which includes a battery pack group, which is composed of 4 battery packs, which are connected in series in pairs and then in parallel, and then connected to three independent and parallel-connected AC / DC modules for outputting three independent single-phase alternating currents, which form a three-phase alternating current. The utility model adopts the method of connecting the battery packs in series first and then in parallel, which can realize both dynamic capacity increase and dynamic capacity reduction.

Description

Technical Field

[0001] The utility model relates to the field of liquid cooling industry and commerce, and in particular to a liquid cooling industry and commerce energy storage integrated machine. Background Art

[0002] Liquid-cooled industrial and commercial energy storage system is an energy storage device that integrates energy storage batteries, battery management systems, liquid cooling systems, and energy management systems. Liquid-cooled industrial and commercial energy storage system is an energy storage device with multiple functions that can meet the needs of industrial and commercial users for efficient, stable, and clean power supply. However, the liquid-cooled industrial and commercial energy storage system currently on the market includes a battery cluster / high-voltage box / PCS / power supply circuit / control circuit, and manages the charging and discharging operations of multiple battery packs (PACK) through a cluster-level controller (BCU). Because the DC-side battery packs of the PCS are all connected in series, the voltage range is limited to manage only specific 5 or 8 battery packs. If a single battery pack fails, the battery voltage will not match the PCS voltage, causing the system to be unable to continue operating. Summary of the invention

[0003] Purpose of the invention: The purpose of the utility model is to provide a liquid-cooled industrial and commercial energy storage integrated machine that can achieve both dynamic capacity expansion and dynamic capacity reduction.

[0004] Technical solution: In order to achieve the above-mentioned purpose of the invention, the utility model provides a liquid-cooled industrial and commercial energy storage integrated machine, including two identical sub-energy storage systems, each sub-energy storage system includes a battery pack group, the battery pack group consists of 4 battery packs, the 4 battery packs are connected in series in pairs and then in parallel, and then connected to three independent and parallel connected AC / DC modules for outputting three independent single-phase alternating currents, and the three independent single-phase alternating currents constitute a three-phase alternating current.

[0005] Furthermore, the power conversion device includes four first switches correspondingly connected to the positive terminals of the battery pack and four first fuses correspondingly connected to the negative terminals of the battery pack.

[0006] Furthermore, each battery pack is connected to a corresponding insulated gate bipolar transistor, and the insulated gate bipolar transistor is connected to the first switch and the AC / DC module respectively.

[0007] Furthermore, the AC / DC module is correspondingly provided with a second fuse.

[0008] Furthermore, it also includes a second switch and a protector and a mutual inductor correspondingly connected to the second switch, and the mutual inductor is correspondingly connected to the contactor and the first transformer in turn.

[0009] Furthermore, it also includes an electric energy meter, a power indicator light, a protection switch, a power supply and a second transformer, and the electric energy meter, the power indicator light, the protection switch, the power supply and the second transformer are connected in parallel on the port connection line.

[0010] Furthermore, the power supply is also provided with a third switch.

[0011] Furthermore, the protector is provided with a third fuse.

[0012] A liquid-cooled industrial and commercial system comprises a grid-connected cabinet and a liquid-cooled industrial and commercial energy storage integrated machine, wherein the grid-connected cabinet is connected to the liquid-cooled industrial and commercial energy storage integrated machine.

[0013] Furthermore, a plurality of the liquid-cooled industrial and commercial energy storage integrated machines are connected to the grid-connected cabinet via a combiner cabinet.

[0014] PCS (Power Conversion System) refers to a power conversion system, which is a device or system that converts other forms of energy into electrical energy. The main function of PCS is to convert renewable energy such as solar energy and wind energy into direct current, and then convert direct current into alternating current for use in homes, businesses or power grids.

[0015] Beneficial effects: The utility model provides a low-voltage power conversion device, which can not only perform pack-level charging and discharging operations by directly connecting to at least two battery packs, physically eliminating the high-voltage box components; it can also change the management granularity of the battery pack from the cluster level to the pack level. When a battery pack in the system fails, the battery packs connected in series with the failed battery pack can be removed, and the remaining battery packs continue to work. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the structure of a liquid-cooled industrial and commercial energy storage device;

[0017] Figure 2 It is a schematic diagram of the structure of a liquid-cooled industrial and commercial system including a single liquid-cooled industrial and commercial energy storage integrated machine;

[0018] Figure 3 It is a schematic diagram of the structure of a liquid-cooled industrial and commercial system in which multiple liquid-cooled industrial and commercial energy storage integrated machines are connected to the grid. DETAILED DESCRIPTION

[0019] A liquid-cooled industrial and commercial energy storage integrated machine includes two identical sub-energy storage systems, each of which includes a battery pack group 1, an electric energy meter 2, a power indicator light 3, a protective switch 4, a power supply 5, a second transformer 6, a second switch 7, and a protector 8 and a mutual inductor 9 corresponding to the second switch 7. The electric energy meter 2, the power indicator light 3, the protective switch 4, the power supply 5 and the second transformer 6 are connected in parallel on the port connection line, and the mutual inductor 9 is connected in sequence with a contactor 10 and a first transformer 11. The battery pack group 1 consists of four battery packs 12, which are connected in series and then in parallel, and then connected to three independent and parallel-connected AC / DC modules 132 for outputting three independent single-phase alternating currents, and the three independent single-phase alternating currents form a three-phase alternating current. The positive terminal of the battery pack group 1 is connected to the positive pole of the power conversion device, and the negative terminal of the battery pack group 1 is connected to the negative pole of the power conversion device. The power conversion device includes four first switches 14 connected to the positive terminals of the battery packs 1 and four first fuses 15 connected to the negative terminals of the battery packs. Each battery pack 1 is connected to an insulated gate bipolar transistor 131, which is connected to the first switch 14 and the AC / DC module 132 respectively. The power supply 5 is also provided with a third switch 16. The protector 8 is provided with a third fuse 17. The AC / DC module 132 is provided with a second fuse 18.

[0020] The above-mentioned mutual inductor 9 is used for current sampling of the electric energy meter 2; the live indicator light 3 is used to display the live status of the cabinet and serve as a warning; the protection switch 4 is used for the liquid-cooled air-conditioning incoming line protection of the liquid-cooled industrial and commercial integrated machine; the protector 8 is an AC surge protector; the third fuse 17 is used for the backup protection of the AC surge protector; the protection switch 4 is used for the liquid-cooled air-conditioning incoming line protection; the power supply 5 is an uninterruptible power supply for the liquid-cooled industrial and commercial integrated machine; the third switch 16 is a load incoming line switch; this circuit is used to provide uninterruptible power supply to important control circuits such as the power conversion device control circuit, BMS, local controller, and fire controller in the integrated machine; the second transformer 6 is a transformer for sampling the mains voltage, which is used to obtain the voltage, frequency and other data of the low-voltage power grid. The contactor 10 is an AC contactor, which is used for AC starting of the power conversion device in the integrated machine; a transformer 11 is used to convert the voltage inverted by the power conversion device into a voltage matching the low-voltage power grid to meet the grid connection requirements. The second fuse 18 is used for short-circuit protection of the AC side of the power conversion device; the insulated gate bipolar transistor 131 is a DC side static switch, used for soft start of the AC / DC DC side; the first switch 14 is a DC side pre-charge switch, used for pre-charge control of the DC side of the power conversion device, and has a certain isolation protection effect; the first fuse 15 is an AC / DC module DC side fuse, used for short-circuit protection of the DC side of the power conversion device;

[0021] Example 1

[0022] like Figure 1 The figure shows an embodiment of the present utility model, including four parallel battery pack groups, each battery pack group includes two series battery packs, wherein after PACK1 is connected in series with PACK2, the positive electrode of PACK1 is connected to the positive electrode incoming port on the K1 side of the power conversion device, and the negative electrode of PACK2 is connected to the negative electrode incoming port on the FU7 side of the power conversion device; after PACK3 is connected in series with PACK4, the positive electrode of PACK3 is connected to the positive electrode incoming port on the K2 side of the power conversion device, and the negative electrode of PACK4 is connected to the negative electrode incoming port on the FU8 side of the power conversion device. After PACK5 is connected in series with PACK6, the positive electrode of PACK5 is connected to the positive electrode incoming port on the K3 side of the power conversion device, and the negative electrode of PACK6 is connected to the negative electrode incoming port on the FU9 side of the power conversion device. After PACK7 is connected in series with PACK8, the positive electrode of PACK7 is connected to the positive electrode incoming port on the K4 side of the power conversion device, and the negative electrode of PACK8 is connected to the negative electrode incoming port on the FU10 side of the power conversion device. As shown in FIG. Figure 1 As shown, PACK1, PACK2 and PACK3, PACK4 are connected in series and then incorporated into the first busbar of the power conversion device, which is supported by three groups of AC / DC modules in parallel. The three groups of AC / DC modules are used as three independent AC / DC modules, and their output voltage and potential are adjusted through high-speed communication between each other. The phase difference between the output of three single-phase alternating currents is 120°, and finally a three-phase alternating current is formed. Similarly, PACK5, PACK6 and PACK7, PACK8 are connected in series and then incorporated into the second busbar of the power conversion device, which is supported by three groups of AC / DC modules in parallel. The three groups of AC / DC modules are used as three independent AC / DC modules, and their output voltage and potential are adjusted through high-speed communication between each other. The phase difference between the output of three single-phase alternating currents is 120°, and finally a three-phase alternating current is formed. The working units of PACK1, PACK2, PACK3, PACK4 and PACK5, PACK6, PACK7, PACK8 are connected in series and operate independently at the DC end. Different from the traditional series connection of all battery packs, the parallel connection method can realize online addition and subtraction of battery packs to achieve the purpose of dynamic capacity expansion. The battery pack addition and subtraction instructions are shown in the figure: PACK1 and PACK2 are the first battery pack, PACK3 and PACK4 are the second battery pack, PACK5 and PACK6 are the third battery pack, and PACK7 and PACK8 are the fourth battery pack. PACK1, PACK2, PACK3, PACK4, PACK5, PACK6, PACK7, and PACK8 are battery packs. FU7, FU8, FU9, and FU10 are the first fuses, and K1, K2, K3, and K4 are the first switches.

[0023] In the present invention, PACK1, PACK2, PACK3, PACK4, PACK5, PACK6, PACK7, and PACK8 are all 48 or 52 energy storage cells connected in series, and the rated capacity of a single energy storage cell can be 280Ah, 314Ah, 320Ah, etc. Taking the most mature battery PACK in the market as an example, the battery pack adopts 280Ah, with a rated voltage of 3.2V. A battery pack has 48 energy storage cells connected in series, and the final rated voltage of a single battery pack is 153.6V. The voltage after two battery packs are connected in series is 307.2V. The present invention adopts a two-parallel and two-string battery pack mode, and the rated voltage of the six AC / DC modules at the DC end is 307.2V, which is within the ideal operating voltage range of the AC / DC module.

[0024] The present embodiment provides a low-voltage power conversion device, in which the battery pack is connected in series and parallel. Pack-level charging and discharging operations can be performed by directly connecting to at least two battery packs, physically eliminating the high-voltage box components, and the management granularity of the battery pack can be changed from cluster level to pack level. When a battery pack in the system fails, the battery pack connected in series with the failed battery pack can be removed, and the remaining battery packs can continue to work.

[0025] As another embodiment of the utility model, when the initial grid-connected capacity of industrial and commercial enterprises is greater than the actual capacity required by users, after a period of operation, one or more of the initially installed four battery packs or eight battery packs can be removed at will to meet the grid-connected requirements. For example, when Figure 1 When the output line of PACK1 in the system fails, the connection lines between the battery packs of PACK1 and PACK2 and the power conversion device are removed, and the remaining battery packs are used normally. Similarly, if other PACKs fail, they can be repaired by removing only the connection lines of this group. After the Pack and all wiring harnesses are removed and short-circuited manually, the power conversion device will first detect the increased battery pack voltage. When the voltage of other battery packs connected in parallel matches the voltage of the newly added battery pack, the newly added battery pack is automatically incorporated into the system by closing the IGBT static switching switch of the power conversion device loop, without affecting the normal operation of the system. When reduced capacity operation is required, the configuration can be automatically completed after the removal of the Pack and cables and the short-circuiting of the control harness, without the need for manual calibration. Traditional industrial and commercial solutions cannot meet this scenario, and storage abandonment will occur.

[0026] As another embodiment of the utility model, when the initial grid-connected capacity of industrial and commercial enterprises is less than the actual capacity required by users, after a period of operation, the initially installed four battery packs and eight battery packs can be arbitrarily increased by one or more battery packs to meet the grid-connected requirements. Traditional industrial and commercial solutions cannot meet this scenario, and customers have to add another energy storage cabinet, which leads to a relatively large increase in costs or over-matching. This embodiment only needs to ensure that the added battery pack cells match the same batch, and directly Figure 1 After being connected in series, they are connected to the corresponding power conversion device port. When the internal stacked busbar voltage is consistent with the newly added battery pack, the power conversion device will turn on the IGBT static soft-start switch and incorporate the new battery pack into the system to achieve the purpose of automatic matching and capacity increase.

[0027] Example 2

[0028] like Figure 2 As shown in the figure, in the liquid-cooled industrial and commercial system, for some single loads or small systems, a single liquid-cooled industrial and commercial all-in-one machine is sufficient. The AC / DC modules and battery packs in this figure are thumbnails, and the actual figure is different from Figure 1 Completely the same, it is 8 battery packs 12 and 6 independent AC / DC modules. The collaborative work between the liquid-cooled industrial and commercial energy storage machine and the grid-connected cabinet can realize energy storage and release, power regulation, protection functions, monitoring and management functions, thereby improving the operating efficiency and stability of the entire system.

[0029] Example 3

[0030] like Figure 3 The AC / DC module and battery pack in this figure are thumbnails. Figure 1 Completely consistent, there are 8 battery packs 12 and 6 independent AC / DC modules. In some large systems or important facilities, such as data centers, hospitals, industrial parks, etc., due to their large energy storage needs or high requirements for power supply reliability, the liquid-cooled industrial and commercial integrated machines of Example 2 can be connected in parallel or in series. This embodiment uses multiple series-connected liquid-cooled industrial and commercial integrated machines to connect to the grid cabinet 19 through the junction cabinet 20 to meet the energy storage needs of the entire system, and improve the reliability and stability of power supply to ensure that the entire system can still operate normally when a certain device fails. The collaborative work between the liquid-cooled industrial and commercial energy storage integrated machine and the grid cabinet 19 can realize energy storage and release, power regulation, protection functions, monitoring and management functions, thereby improving the operating efficiency and stability of the entire system.

[0031] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A liquid-cooled industrial and commercial energy storage integrated machine, characterized in that: It includes two identical sub-energy storage systems, each of which includes a battery pack group, which consists of 4 battery packs. The 4 battery packs are connected in series in pairs and then in parallel, and then connected to three independent AC / DC modules connected in parallel to output three independent single-phase alternating currents. The three independent single-phase alternating currents form a three-phase alternating current.

2. The liquid-cooled industrial and commercial energy storage integrated machine according to claim 1, characterized in that: The positive terminal of the battery pack is connected to the positive terminal of the power conversion device, and the negative terminal of the battery pack is connected to the negative terminal of the power conversion device; the power conversion device includes four first switches connected to the positive terminal of the battery pack and four first fuses connected to the negative terminal of the battery pack.

3. The liquid-cooled industrial and commercial energy storage integrated machine according to claim 2, characterized in that: Each battery pack is connected to a corresponding insulated gate bipolar transistor, and the insulated gate bipolar transistor is connected to the first switch and the AC / DC module respectively.

4. The liquid-cooled industrial and commercial energy storage integrated machine according to claim 1, characterized in that: The AC / DC module is correspondingly provided with a second fuse.

5. The liquid-cooled industrial and commercial energy storage integrated machine according to claim 1, characterized in that: It also includes a second switch and a protector and a mutual inductor connected to the second switch, wherein the mutual inductor is connected to a contactor and a first transformer in turn.

6. The liquid-cooled industrial and commercial energy storage integrated machine according to claim 4, characterized in that: It also includes an electric energy meter, a power indicator light, a protection switch, a power supply and a second transformer. The electric energy meter, the power indicator light, the protection switch, the power supply and the second transformer are connected in parallel on the port connection line.

7. The liquid-cooled industrial and commercial energy storage integrated machine according to claim 6, characterized in that: The power supply is also provided with a third switch.

8. The liquid-cooled industrial and commercial energy storage integrated machine according to claim 5, characterized in that: The protector is provided with a third fuse.

9. A liquid cooling industrial and commercial system, characterized in that: It comprises a grid-connected cabinet and a liquid-cooled industrial and commercial energy storage integrated machine as described in any one of claims 1 to 8, wherein the grid-connected cabinet is connected to the liquid-cooled industrial and commercial energy storage integrated machine.

10. A liquid cooling industrial and commercial system according to claim 9, characterized in that: A plurality of the liquid-cooled industrial and commercial energy storage integrated machines are connected to the grid-connected cabinet via a combiner cabinet.

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