A unidirectional dual-input acdc-based energy storage charging system

Abstract

The utility model relates to the technical field of energy storage charging current, especially to a kind of energy storage charging system based on one-way double-input ACDC, including power grid, energy storage battery cluster, charging gun and one-way double-input ACDC equipment;The one-way double-input ACDC equipment includes AC input end, DC input end and DC output end;The power grid is connected to the AC input end by first switch;The energy storage battery cluster is connected to the DC input end by second switch;The charging gun is connected to the DC output end by third switch.The utility model aims at providing a kind of energy storage charging system based on one-way double-input ACDC, using the technical scheme provided by the utility model to realize energy storage and charging using one-way double-input ACDC, also can realize the function of automobile reverse discharge to energy storage battery by charging gun, save the number of power module, greatly reduce equipment cost.

Description

Technical Field

[0001] This utility model relates to the field of energy storage charging current technology, and in particular to an energy storage charging system based on unidirectional dual-input ACCDC. Background Technology

[0002] In a charging system consisting of a power grid and energy storage battery clusters, a bidirectional DC / DC converter is required. A bidirectional AC / DC converter is needed between the power grid and the energy storage battery clusters to convert the AC power from the grid into DC power to supply the energy storage battery clusters for charging. Similarly, a bidirectional DC / DC converter is needed between the battery clusters and the charging gun to convert the DC power from the energy storage battery clusters to the DC power required by the charging gun for charging.

[0003] Therefore, a charging system with energy storage battery clusters requires at least two bidirectional devices to achieve energy storage and charging, resulting in many modules and high costs. Utility Model Content

[0004] The purpose of this invention is to provide an energy storage and charging system based on a unidirectional dual-input AC-CDC. The technical solution provided by this invention uses a unidirectional dual-input AC-CDC to achieve energy storage and charging, and can also realize the function of reverse discharge from the car to the energy storage battery through the charging gun, saving the number of power modules and significantly reducing equipment costs.

[0005] To achieve the aforementioned objectives, this invention provides an energy storage and charging system based on a unidirectional dual-input AC-CDC converter, comprising a power grid, an energy storage battery cluster, a charging gun, and a unidirectional dual-input AC-CDC device; the unidirectional dual-input AC-CDC device includes an AC input terminal, a DC input terminal, and a DC output terminal; the power grid is connected to the AC input terminal via a first switch; the energy storage battery cluster is connected to the DC input terminal via a second switch; and the charging gun is connected to the DC output terminal via a third switch.

[0006] When the first and third switches are closed and the second switch is open, the AC power from the power grid is converted into DC power through the unidirectional dual-input ACDC device to power the charging gun.

[0007] When the second and third switches are closed and the first switch is open, the DC power from the energy storage battery cluster is converted into DC power by the unidirectional dual-input ACDC device to power the charging gun.

[0008] Preferably, the energy storage battery cluster is also connected to the DC output terminal via a fourth switch;

[0009] When the first and fourth switches are closed and the second and third switches are open, the alternating current from the power grid is converted into direct current through the unidirectional dual-input ACDC device to charge the energy storage battery cluster.

[0010] Preferably, the charging gun is also connected to the DC input terminal via a fifth switch;

[0011] When the fourth and fifth switches are closed, and the first, second, and third switches are open, the DC power on the charging gun is converted into DC power by the unidirectional dual-input ACDC device to charge the energy storage battery cluster in reverse.

[0012] Preferably, there are two or more of the energy storage battery cluster, the unidirectional dual-input ACDC device, the first switch, the second switch, the third switch, the fourth switch, and the fifth switch; the energy storage battery cluster is short-circuited through the sixth switch and then connected to the second and fourth switches; a seventh switch is also provided at the short-circuit point.

[0013] Compared with existing technologies, this utility model connects the energy storage battery cluster to a unidirectional dual-input ACDC device. During nighttime periods of low electricity prices, AC power is output from the grid, and the unidirectional dual-input ACDC device converts the AC power into DC power to charge the energy storage battery cluster. During the daytime, when the charging gun discharges, the energy storage battery cluster or the grid provides power. To enable a vehicle to discharge to the energy storage battery cluster via the charging gun, simply change the switch state. This utility model allows switching between different operating modes using a switch and a unidirectional dual-input ACDC device, eliminating the need for multiple bidirectional DCDC devices, thus reducing costs. In addition to the normal state where the energy storage battery cluster or the grid discharges to the charging gun, it also allows a vehicle to discharge to the energy storage battery via the charging gun. The charging gun device has no limit on its maximum power or the maximum number of energy storage battery clusters that can be connected in parallel, offering flexibility and strong applicability. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the circuit connection of the energy storage and charging system according to Embodiment 1 of this utility model;

[0015] Figure 2 This is a schematic diagram of the energy storage and charging system of Embodiment 1 of this utility model, in which the power grid supplies power to the charging gun.

[0016] Figure 3 This is a schematic diagram of the energy storage battery cluster powering the charging gun in the energy storage and charging system of Embodiment 1 of this utility model;

[0017] Figure 4 This is a schematic diagram of the power grid charging mode for the energy storage battery cluster in Embodiment 1 of this utility model.

[0018] Figure 5This is a schematic diagram of the reverse charging mode of the energy storage battery cluster in the energy storage charging system of Embodiment 1 of this utility model.

[0019] Figure 6 This is a schematic diagram of the circuit connection of the energy storage and charging system according to Embodiment 2 of this utility model;

[0020] Figure 7 This is a schematic diagram of the energy storage and charging system of Embodiment 2 of this utility model, in which the power grid supplies power to the charging gun.

[0021] Figure 8 This is a schematic diagram of the energy storage battery cluster powering the charging gun in Embodiment 2 of the present invention.

[0022] Figure 9 This is a schematic diagram of the power grid charging mode for the energy storage battery cluster in Embodiment 2 of this utility model.

[0023] Figure 10 This is a schematic diagram of the reverse charging mode of the energy storage battery cluster in the energy storage charging system of Embodiment 2 of this utility model. Detailed Implementation

[0024] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0025] Example 1

[0026] In a charging system consisting of a power grid and a cluster of energy storage batteries, bidirectional DC / DC devices are required, and at least two bidirectional devices are needed to achieve energy storage and charging. This results in numerous modules and high costs.

[0027] To address the aforementioned technical problems, this embodiment provides a device that implements a novel storage and charging mode through a unidirectional dual-input AC-DC converter.

[0028] A unidirectional dual-input ACDC converter allows current to flow only in one direction, achieving a single voltage conversion function. Due to its simplicity and reliability, unidirectional converters are widely used in many fields, such as power management in consumer electronics and voltage regulation in industrial equipment. They play a crucial role, especially in applications requiring stable output voltage. Unidirectional converters can achieve high conversion efficiency under specific operating conditions. This embodiment uses a unidirectional dual-input ACDC converter to address the high cost of current bidirectional devices.

[0029] Please see Figure 1 Specifically, the energy storage and charging system provided in this embodiment includes a power grid 10, an energy storage battery cluster 20, a charging gun 30, and a unidirectional dual-input ACDC device 40.

[0030] The unidirectional dual-input AC-CDC device 40 includes an AC input terminal 41, a DC input terminal 42, and a DC output terminal 43. In terms of connection structure, the power grid 10 is connected to the AC input terminal 41 via a first switch 51, the energy storage battery cluster 20 is connected to the DC input terminal 42 via a second switch 52, and the charging gun 30 is connected to the DC output terminal 43 via a third switch 53.

[0031] Please see Figure 2 When the power grid 10 is needed to power the charging gun, the first switch 51 and the third switch 53 are closed, and the second switch 52 is open. The AC power from the power grid 10 is introduced into the AC input terminal 41 of the unidirectional dual-input ACDC device 40 through the first switch 51. The AC power completes the voltage and current conversion in the unidirectional dual-input ACDC device 40 and is converted into DC power to meet the charging requirements of the charging gun. It is then output from the DC output terminal 43 and then used to power the charging gun 30 through the third switch 53.

[0032] Please see Figure 3 When the energy storage battery cluster 20 is required to power the charging gun, that is, during the peak power supply period of the power grid 10, the second switch 52 and the third switch 53 are closed, and the first switch 51 is open. The DC power of the energy storage battery cluster 20 is introduced into the DC input terminal 42 of the unidirectional dual-input ACDC device 40 through the second switch 52. The DC power completes the voltage and current conversion in the unidirectional dual-input ACDC device 40 and is converted into DC power that meets the charging requirements of the charging gun. It is then output from the DC output terminal 43 and then used to power the charging gun 30 through the third switch 53.

[0033] Please see Figure 4 In addition, this embodiment can also charge the energy storage battery cluster 20 through the power grid 10. Charging can be completed during off-peak hours when the power grid 10 is not supplying electricity. Specifically, the energy storage battery cluster 20 is connected to the DC output terminal 43 through the fourth switch 54. When it is necessary to charge the energy storage battery cluster 20, the first switch 51 and the fourth switch 54 are closed, and the second switch 52 and the third switch 53 are open. The AC power from the power grid 10 is introduced into the AC input terminal 41 of the unidirectional dual-input ACDC device 40 through the first switch 51. The AC power is converted into DC power that meets the charging requirements of the energy storage battery cluster 20 within the unidirectional dual-input ACDC device 40. After being output from the DC output terminal 43, it is then used to charge the energy storage battery cluster 20 through the fourth switch 54.

[0034] To improve the practicality of the energy storage charging system provided in this embodiment, a V2G mode is also added, which refers to electric vehicles supplying power to the energy storage battery cluster 20 in reverse, utilizing the energy stored in a large number of electric vehicles as a buffer between the power grid 10 and renewable energy sources. Specifically, the charging gun 30 is connected to the DC input terminal 42 via the fifth switch 55.

[0035] Please see Figure 5 When the system needs to switch to V2G mode, the fourth switch 54 and the fifth switch 55 are closed, and the first switch 51, the second switch 52 and the third switch 53 are opened. The charging gun 30 is inserted into the electric vehicle to obtain DC power from the electric vehicle. The DC power is then introduced into the DC input terminal 42 of the unidirectional dual-input ACDC device 40 through the fifth switch 55. The DC power is converted into voltage and current within the unidirectional dual-input ACDC device 40 to meet the DC power required for charging the energy storage battery cluster 20. The DC power is then output from the DC output terminal 43 and then charged through the fourth switch 54 to charge the energy storage battery cluster 20.

[0036] In summary, the energy storage charging system provided in this embodiment connects the energy storage battery cluster 20 to the unidirectional dual-input ACDC device 40. During nighttime periods of low electricity prices, the grid 10 outputs AC power, which the unidirectional dual-input ACDC device 40 converts to DC power to charge the batteries in the energy storage battery cluster 20. During the daytime, when the charging gun 30 discharges, it is powered by either the energy storage battery cluster 20 or the grid 10. To enable the vehicle to discharge to the energy storage battery cluster 20 via the charging gun 30, the switch state can be changed. This invention allows switching between different operating modes using a switch and the unidirectional dual-input ACDC device 40, eliminating the need for multiple bidirectional DCCDC devices and reducing costs. In addition to the normal state where the energy storage battery cluster 20 or the grid 10 discharges to the charging gun 30, it also enables the vehicle to discharge to the energy storage battery via the charging gun 30. The charging gun 30 has no limit on its maximum power or the maximum number of energy storage battery clusters 20 that can be connected in parallel, making it flexible and highly applicable.

[0037] Example 2

[0038] Please see Figure 6 To improve the practicality of the energy storage charging system, this embodiment differs from Embodiment 1 in that it includes two or more energy storage battery clusters 20, unidirectional dual-input ACDC devices 40, first switches 51, second switches 52, third switches 53, fourth switches 54, and fifth switches 55. The figure shows the circuit connection diagram for two energy storage battery clusters 20. The energy storage battery clusters 20 are short-circuited via the sixth switch 56, and then connected to the second switch 52 and the fourth switch 54; a seventh switch 57 is also provided at the short-circuit point.

[0039] In this embodiment, the number of energy storage battery clusters 20 is unlimited and can be adjusted arbitrarily according to the application site. It also has four working modes, including the grid 10 supplying power to the charging gun, the energy storage battery clusters 20 supplying power to the charging gun, the grid 10 charging the energy storage battery clusters 20, and the charging gun 30 reversing the charging of the energy storage battery clusters 20.

[0040] Please see Figures 7 to 10 In the four working modes of powering the charging gun from the grid, powering the charging gun from the energy storage battery cluster, charging the energy storage battery cluster from the grid, and reverse charging the energy storage battery cluster from the charging gun, the switching of the working mode is achieved by closing and opening the seven switches: the first switch 51, the second switch 52, the third switch 53, the fourth switch 54, the fifth switch 55, the sixth switch 56, and the seventh switch 57.

[0041] By using two or more energy storage battery clusters 20 as energy storage mechanisms, the energy storage capacity is increased. On this basis, the charging gun 30 has no limit on the maximum charging power and can be used in cars with different charging power.

[0042] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. An energy storage and charging system based on unidirectional dual-input AC-DC converters, characterized in that: The system includes a power grid, an energy storage battery cluster, a charging gun, and a unidirectional dual-input AC-CDC device. The unidirectional dual-input AC-CDC device includes an AC input terminal, a DC input terminal, and a DC output terminal. The power grid is connected to the AC input terminal via a first switch. The energy storage battery cluster is connected to the DC input terminal via a second switch. The charging gun is connected to the DC output terminal via a third switch. When the first and third switches are closed and the second switch is open, the AC power from the power grid is converted into DC power through the unidirectional dual-input ACDC device to power the charging gun. When the second and third switches are closed and the first switch is open, the DC power from the energy storage battery cluster is converted into DC power by the unidirectional dual-input ACDC device to power the charging gun. The energy storage battery cluster is also connected to the DC output terminal via a fourth switch; When the first and fourth switches are closed and the second and third switches are open, the AC power from the power grid is converted into DC power by the unidirectional dual-input ACDC device to charge the energy storage battery cluster. The charging gun is also connected to the DC input terminal via a fifth switch; When the fourth and fifth switches are closed, and the first, second, and third switches are open, the DC power on the charging gun is converted into DC power by the unidirectional dual-input ACDC device to charge the energy storage battery cluster in reverse.

2. The energy storage and charging system according to claim 1, characterized in that: The energy storage battery cluster, the unidirectional dual-input ACDC device, the first switch, the second switch, the third switch, the fourth switch, and the fifth switch are all in pairs or more; the energy storage battery cluster is short-circuited through the sixth switch and then connected to the second and fourth switches; a seventh switch is also provided at the short-circuit point.

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