Power distribution device and charging system
By designing a power distribution device that includes one or two power conversion devices and utilizing the connection method of controllable switches, the problem of flexible allocation of each power unit is solved when expanding the power distribution device of new energy vehicles, under the premise of minimizing the number of controllable switches, thereby reducing the complexity of the device and the probability of failure.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- XIAN LINCHR NEW ENERGY TECH CO LTD
- Filing Date
- 2025-06-10
- Publication Date
- 2026-05-12
AI Technical Summary
While expanding the power distribution device to accommodate the increasing number of new energy vehicles, how can we achieve flexible allocation of each power unit while ensuring the minimum number of controllable switches, and avoid increasing the complexity of the device and the probability of failure?
Design a power distribution device comprising one or two power conversion devices, each device including nine power units. The connection of controllable switches is designed through a controllable connection method. By limiting the connection method of the power units, flexible allocation of each power unit is achieved, ensuring that the connection method of each power unit minimizes the flexible allocation of each power unit.
When expanding the power distribution device to a very high power level, the expansion of the power distribution device is achieved by limiting the expansion of the power distribution device, which enables flexible allocation of the power distribution device and minimizes the number of controllable switches used.
Smart Images
Figure CN224224924U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of power supply technology for new energy vehicles, and in particular to a power distribution device and a charging system. Background Technology
[0002] With the surge in the number of new energy vehicles and the promotion of renewable energy, optimizing the layout of power distribution devices and charging systems has become increasingly important, as it is crucial for improving the convenience of electric transportation, promoting green travel, and building a sustainable transportation ecosystem.
[0003] However, when designing power distribution devices and charging systems, there is a conflict between expanding the power distribution device to a higher power level, being compatible with the minimum number of controllable switches, and having more flexible allocation of power among the units in the power distribution device. Utility Model Content
[0004] The main objective of this application is to provide a power distribution device and a charging system, which aims to solve the technical problem that when expanding a power distribution device with ultra-high power, it is impossible to achieve flexible allocation of each power unit while ensuring the minimum number of controllable switches used.
[0005] To achieve the above objectives, this application provides a power distribution device, comprising: one or two power conversion devices; the power distribution device includes M controllable switches, and each power conversion device includes 9 power units; wherein, when there is one power conversion device, M equals 12, and each power unit is connected to other power units through a controllable switch; when there are two power conversion devices, M equals 24, and at least one power unit in one power conversion device is connected to a power unit in another power conversion device through a controllable switch.
[0006] Optionally, when there is only one power conversion device, the nine power units in the power conversion device respectively form a first fully enclosed ring path, a first inner ring path, and a first outer ring path. Each power unit is connected to other power units through at most two power units. Specifically, the first power unit, the second power unit, the third power unit, the ninth power unit, the eighth power unit, and the seventh power unit are connected sequentially through a controllable switch to form the first fully enclosed ring path. The seventh power unit is connected to the ninth power unit through a controllable switch to form the first outer ring path. The fifth power unit is connected to the sixth power unit, the fourth power unit, and the eighth power unit through a controllable switch to form a first sub-path. The sixth power unit is connected to the first power unit through a controllable switch to form a second sub-path. The fourth power unit is connected to the third power unit through a controllable switch to form a third sub-path. The first sub-path, the second sub-path, and the third sub-path constitute the first inner ring path.
[0007] Optionally, when there are two power conversion devices, the two power conversion devices include a first power conversion device and a second power conversion device, and the first power conversion device and the second power conversion device have the same topology.
[0008] Optionally, the four power units in the first power conversion device are connected to the four power units in the second power conversion device via controllable switches, and each power unit is connected to other power units via up to four power units.
[0009] Optionally, the nine power units in the first power conversion device and the second power conversion device respectively form a second fully enclosed ring path and a second inner ring path; wherein, the first power unit, the second power unit, the third power unit, the fourth power unit, the ninth power unit, the eighth power unit, the seventh power unit and the sixth power unit are connected in sequence through a controllable switch to form the second fully enclosed ring path; the fifth power unit is connected to the second power unit and the eighth power unit through a controllable switch to form the second inner ring path.
[0010] Optionally, the third power unit in the first power conversion device is connected to the first power unit in the second power conversion device via a controllable switch; the sixth power unit in the first power conversion device is connected to the sixth power unit in the second power conversion device via a controllable switch; the fourth power unit in the first power conversion device is connected to the fourth power unit in the second power conversion device via a controllable switch; and the ninth power unit in the first power conversion device is connected to the seventh power unit in the second power conversion device via a controllable switch.
[0011] Optionally, the power conversion device includes multiple charging gun connection interfaces for connecting charging guns, and the number of charging guns is less than or equal to the number of power units.
[0012] Optionally, the power unit is an AC-DC conversion unit used to convert AC power into DC power and output DC power.
[0013] Optionally, the controllable switch includes at least one of a contactor, a relay, and / or a solid-state switch.
[0014] In addition, to achieve the above objectives, this application also provides a charging system, including the power distribution device, controller, and charging terminal, wherein the controller and the controllable switch are communicatively connected.
[0015] This application proposes a power distribution device and charging system. The power distribution device includes one or two power conversion devices. By limiting the number of controllable switches in the power distribution device and specifying the connection relationship of each power unit, the problem of flexibly allocating power units while ensuring a minimum number of controllable switches is achieved for ultra-high power distribution devices. This enables flexible allocation of power units when expanding ultra-high power distribution devices, while minimizing the number of controllable switches used. Attached Figure Description
[0016] Figure 1 This is a schematic diagram of a first structure of a power distribution device provided in an embodiment of this application;
[0017] Figure 2 This is a second structural schematic diagram of a power distribution device provided in an embodiment of this application.
[0018] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation
[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.
[0020] In this application, unless otherwise expressly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.
[0021] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution where both A and B are satisfied simultaneously. Furthermore, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.
[0022] In the existing technology, due to the increase in the number of new energy vehicles, there is a need to expand the power distribution device to a higher power. However, when expanding the power distribution device to a higher power, there is a conflict between being compatible with the use of the minimum number of controllable switches and being able to allocate power to each unit in the power distribution device more flexibly.
[0023] To address the aforementioned problems, this application provides a power distribution device and a charging system, the details of which are described below.
[0024] Please refer to Figure 1 , Figure 1 This is a schematic diagram of a first structure of a power distribution device provided in an embodiment of this application. The power distribution device may include: a power conversion device, which includes 9 power units and up to 12 controllable switches. Each power unit is connected to other power units through up to 3 controllable switches, that is, each power unit is connected to other power units through up to 2 power units.
[0025] All power units are AC / DC (Alternating Current / Direct Current) converters, used to convert AC power into DC power and output DC power. The power unit has a power granularity of 40kW, and the total power of the power conversion device is 360kW. The input terminal of each power unit is electrically connected to a 380V AC mains power supply, and the output terminal is electrically connected to other power units to achieve cascading (series or parallel connection). In this embodiment, when the controllable switch connecting two power units remains closed, the two power units are connected in parallel, i.e., their DC terminals are connected in parallel, so the total output power is the sum of the output power of the two power units.
[0026] The controllable switch's control terminal is connected to a control module to turn on or off in response to the switch control signal output by the control module. This allows for flexible adjustment of different power units by controlling each controllable switch. For example, the controllable switch can be at least one of a contactor, relay, and / or solid-state switch.
[0027] It should be noted that the power unit can convert the high-voltage AC power from the power grid into the low-voltage DC power required by new energy vehicles, perform signal processing to monitor the charging status, and support communication with the management system to achieve intelligent charging. The controllable switch K can safely switch high-power current under low-power signals, and can thus be used to control the on / off state of the circuit, realizing the transition between charging, standby, and power-off modes. This achieves automated management of the charging process, ensuring stable operation of the power distribution device and charging system under different operating conditions, and protecting the safety of users and equipment. It is understood that the controllable switch can be in a closed or open state.
[0028] In this exemplary embodiment, please continue to refer to Figure 1 The power conversion device 100 includes nine power units, namely: first power unit 1, second power unit 2, ..., ninth power unit 12. The nine power units respectively form a first fully enclosed ring path, a first inner ring path and a first outer ring path.
[0029] In this circuit, the first power unit 1, the second power unit 2, the third power unit 3, the ninth power unit 9, the eighth power unit 8, and the seventh power unit 7 are connected sequentially through controllable switches KM1, KM2, KM10, KM9, KM8, and KM7 to form a first fully enclosed ring path; the seventh power unit 7 is connected to the ninth power unit 9 through controllable switch KM12 to form a first outer ring path; the fifth power unit 5 is connected to the sixth power unit 6, the fourth power unit 4, and the eighth power unit 8 through controllable switches KM5, KM4, and KM11 to form a first sub-path; the sixth power unit 6 is connected to the first power unit 1 through controllable switch KM6 to form a second sub-path; the fourth power unit 4 is connected to the third power unit 3 through controllable switch KM3 to form a third sub-path; and the first, second, and third sub-paths constitute the inner ring path.
[0030] This embodiment takes the first power unit 1 and the ninth power unit 9 as examples for specific explanation. The first power unit 1 is first connected to the seventh power unit 7 through the controllable switch KM7. The seventh power unit 7 is connected to the ninth power unit 9 through the controllable switch KM12. That is, each power unit can be connected to other power units through at most 2 controllable switches, thereby enabling flexible allocation of each power unit while being compatible with the minimum number of relays.
[0031] It should be noted that, based on the above connection method, when a fault occurs during charging, the system can control a controllable switch to quickly disconnect the faulty power unit, thus isolating it and ensuring the safe and stable operation of the entire power distribution device, reducing the impact on other power units. At the same time, this connection method also facilitates the maintenance and management of the power distribution device; operators can easily perform maintenance on individual power conversion devices without affecting the normal operation of other units.
[0032] It should be understood that Figure 1 This is merely one example; in this embodiment, the power conversion device may also be two, as detailed below with reference to the appendix. Figure 2 The working principle and results of the power distribution device provided in this application are further explained.
[0033] In an exemplary embodiment, please refer to Figure 2 , Figure 2This is a second structural schematic diagram of a power distribution device provided in an embodiment of this application. The total power of the power conversion device is 720 kW. The power distribution device may include 24 controllable switches. The topology of the two power conversion devices in the power distribution device is the same. The two power conversion devices can be a first power conversion device 210 and a second power conversion device 220. The four power units in the first power conversion device 210 and the four power units in the second power conversion device 220 are connected to each other through controllable switches. Each power unit in the power distribution device is connected to other power units through at most 5 controllable switches, that is, each power unit is connected to other power units through at most 4 power units.
[0034] It should be noted that the two power conversion devices have the same topology, that is, the number of power units in the two power conversion devices is the same, namely 9 power units, and the connection relationship of all power units in the two power conversion devices is the same.
[0035] For example, please continue reading Figure 2 This embodiment takes the first power conversion device 210 as an example for explanation. The first power conversion device 210 includes 9 power units, namely: first power unit 1, second power unit 2, ..., ninth power unit 9. The 9 power units respectively form the second fully enclosed ring path and the second ring inner path.
[0036] Among them, the first power unit 1, the second power unit 2, the third power unit 3, the fourth power unit 4, the ninth power unit 9, the eighth power unit 8, the seventh power unit 7 and the sixth power unit 6 are connected in sequence through controllable switches KM1, KM2, KM3, KM8, KM10, KM9, KM6 and KM5 to form a second fully enclosed ring path; the fifth power unit 5 is connected to the second power unit 2 and the eighth power unit 8 through controllable switches KM4 and KM7 respectively to form a second inner ring path.
[0037] For further information, please continue to refer to [link / reference]. Figure 2 The third power unit 3 in the first power conversion device 210 is connected to the first power unit 1 in the second power conversion device 220 via a controllable switch KM21; the sixth power unit 6 in the first power conversion device 210 is connected to the sixth power unit 6 in the second power conversion device 220 via a controllable switch KM22; the fourth power unit 4 in the first power conversion device 210 is connected to the fourth power unit 4 in the second power conversion device 220 via a controllable switch KM23; and the ninth power unit 9 in the first power conversion device 210 is connected to the seventh power unit 7 in the second power conversion device 220 via a controllable switch KM24.
[0038] It should be noted that, in Figure 2 In the illustrated embodiment, since the first power conversion device 210 and the second power conversion device 220 have the same topology, in order to facilitate the differentiation of each power unit in the first power conversion device 210 and the second power conversion device 220, Figure 2 In the second power conversion device 220, the first power unit 1, the second power unit 2, ..., the ninth power unit 9 are sequentially labeled as the thirteenth power unit 13, the fourteenth power unit 14, ..., the eighteenth power unit 18.
[0039] Understandably, for power distribution devices requiring ultra-high power, directly connecting all power units in pairs via controllable switches would require a large number of controllable switches. This increases the complexity of the power distribution device, raises the cost and design difficulty, and increases the probability of failure. Additionally, controllable switches introduce a certain delay during operation, and the combined operation of many controllable switches may lead to longer response times, thus affecting charging efficiency. In this embodiment, by adding four sets of controllable switches and several wires, it is possible to interconnect two identical power conversion devices with only four controllable switches. Furthermore, each power unit can be connected to other power units through at most two controllable switches, achieving compatibility with the minimum number of controllable switches while ensuring flexible allocation of power units in the two power conversion devices.
[0040] Of course, in other embodiments, at least one other power unit in the first power conversion device 210 can be connected to the power unit in the second power conversion device 220 through a controllable switch, or only the connection between the third power unit 3 in the first power conversion device 210 and the first power unit 1 in the second power conversion device 220 can be retained, which can also realize the interconnection of the first power conversion device 100 and the second power conversion device 200.
[0041] In an exemplary embodiment, each power conversion device includes multiple charging gun connection interfaces for connecting charging guns, and the number of charging guns is less than or equal to the number of power units. It is understood that any charging gun can flexibly allocate power to all power units.
[0042] Please see Figure 1 The power conversion device 100 includes nine charging gun connection interfaces for connecting charging guns. Except for the first power unit 1, the third power unit 3 and the fifth power unit 5, each of the other power units is connected to a charging gun through a charging gun connection interface.
[0043] Specifically, the second power unit 2 is connected to the F charging gun via a charging gun connection interface, the fourth power unit 4 is connected to the C charging gun via a charging gun connection interface, the sixth power unit 6 is connected to the A charging gun via a charging gun connection interface, the ninth power unit 9 is connected to the B charging gun via a charging gun connection interface, the eighth power unit 8 is connected to the E charging gun via a charging gun connection interface, the seventh power unit 7 is connected to the D charging gun via a charging gun connection interface, and the sixth power unit 6 is connected to the A charging gun via a charging gun connection interface.
[0044] Please continue to refer to this. Figure 1 If charging gun A is used to call the third power unit 3, the system can control the controllable switches KM6, KM1, and KM2 to close, thereby connecting the sixth power unit 6 to the first power unit 1, the first power unit 1 to the second power unit 2, and the second power unit 2 to the third power unit 3. Thus, charging gun A can call the third power unit 3 through each connected power unit. The system can also control the controllable switches KM5, KM4, and KM3 to close, thereby connecting the sixth power unit 6 to the fifth power unit 5, the fifth power unit 5 to the fourth power unit 4, and the fourth power unit 4 to the third power unit 3. Thus, charging gun A can call the third power unit 3 through each connected power unit.
[0045] Understandably, in Figure 1 In this embodiment, a power unit directly connected to any charging gun can call any power unit by only two power units.
[0046] Please see Figure 2 The first power conversion device 210 and the second power conversion device 220 both include nine charging gun connection interfaces for connecting charging guns. Taking the first power conversion device 210 as an example, all power units except the fifth power unit 5 are connected to a charging gun one by one through a charging gun connection interface.
[0047] Specifically, the first power unit 1 is connected to the E charging gun via a charging gun connection interface, the second power unit 2 is connected to the A charging gun via a charging gun connection interface, the third power unit 3 is connected to the B charging gun via a charging gun connection interface, the fourth power unit 4 is connected to the N charging gun via a charging gun connection interface, the sixth power unit 6 is connected to the M charging gun via a charging gun connection interface, the seventh power unit 7 is connected to the F charging gun via a charging gun connection interface, the eighth power unit 8 is connected to the I charging gun via a charging gun connection interface, and the ninth power unit 9 is connected to the J charging gun via a charging gun connection interface.
[0048] Please continue to refer to this. Figure 2If the E-charging gun is used to call the eighteenth power unit 18, the system can control the controllable switches KM5, KM22, KM16, KM19, and KM20 to close, thereby connecting the first power unit 1 with the sixth power unit 6, the sixth power unit 6 with the fifteenth power unit 15, the fifteenth power unit 15 with the sixteenth power unit 16, the sixteenth power unit 16 with the seventeenth power unit 17, and the seventeenth power unit 17 with the eighteenth power unit 18. Thus, the E-charging gun can call the eighteenth power unit 18 through each connected power unit.
[0049] Understandably, in Figure 2 In this embodiment, a power unit directly connected to any charging gun can call any power unit through only 4 power units.
[0050] It is understood that the number of charging guns connected to the first power conversion device 210 and the second power conversion device 220 through the charging gun connection interface can be the same or different. The number of charging guns connected to the first power conversion device 210 and the second power conversion device 220 through the charging gun connection interface can be allocated according to the actual charging needs, and then the charging guns can be connected to the power units in each power conversion device through a charging gun connection interface.
[0051] For example, if the charging system needs to connect 16 charging guns, the first power conversion device 210 can be selected to connect 8 guns and the second power conversion device 220 can be selected to connect 8 guns, or the first power conversion device 210 can be selected to connect 9 guns and the second power conversion device 220 can be selected to connect 7 guns, or the first power conversion device 210 can be selected to connect 7 guns and the second power conversion device 220 can be selected to connect 7 guns.
[0052] It should be noted that the output terminals of each power unit can not only be connected to other power units, but also be electrically connected to a charging gun through a charging gun connection interface. That is, the input terminals of each power unit can be electrically connected to 380V AC mains power, and the output terminals can be connected to other power units and / or charging guns.
[0053] In the specific implementation process, when using a charging gun to charge a vehicle, the charging gun can be connected to the vehicle to be charged. The electrical energy accumulated by at least a portion of the power units connected to the charging gun's connection interface is output to the vehicle to be charged through the charging gun.
[0054] Another embodiment of this application provides a charging system including at least two power modules, a controller, a power distribution device, and at least one charging interface. The power distribution device is connected to the controller, each power module, and each charging interface. The power modules convert AC power from the power grid into DC power to supply the charging interfaces. The controller is communicatively connected to a controllable switch. The controller acquires the power demand of each charging interface and generates a scheduling command based on the connection relationship of the controllable switch in the power distribution device and the power demand. The power distribution device controls the opening or closing of the controllable switch according to the scheduling command to distribute the output power of each power module to each charging interface.
[0055] In one optional implementation, the charging system provided in this application is an integrated DC charging pile, with a charging interface for connecting a charging gun, and the charging gun being hung on the host of the charging system via a gun mount on the main body of the charging system.
[0056] In one optional implementation, the charging system provided in this application is a split-type DC charging pile. The charging system also includes multiple charging terminals. The charging interface is used to connect the charging terminals. The charging terminals are set separately from the main body of the charging system. The charging terminals are equipped with a single charging gun or dual charging guns for outputting power to electric vehicles.
[0057] For example, the charging terminal can be a charging gun or a terminal in a split power distribution device. This exemplary embodiment takes a charging gun as an example. When the charging gun is used to charge the vehicle to be charged, the controller can first determine the number of charging guns that are charging at the same time, and control the on / off state of the controllable switches connecting the two power conversion devices and the controllable switches in each power conversion device according to the power required by each charging gun, so as to obtain the power required by each charging gun and thus realize the simultaneous charging of each charging gun.
[0058] In the specific implementation process, the controllable switch can be opened or closed under the control of the controller to realize the parallel combination of different power units, that is, to achieve different power outputs.
[0059] Understandably, the controller is responsible for managing and coordinating all aspects of the charging process. It can intelligently adjust the charging strategy by monitoring parameters such as the battery status, charging current, and voltage of the new energy vehicle, thereby controlling the opening and closing of controllable switches to ensure efficient and safe charging. Simultaneously, the controller is also responsible for fault detection and protection during the charging process, ensuring timely power cut-off in cases of overload, short circuit, or abnormal temperature, thus protecting the equipment and user safety. Furthermore, the controller supports communication with the management system, enabling remote monitoring and management, and enhancing the level of intelligence in the charging process.
[0060] The power distribution device is installed within the charging system, enabling the charging of new energy vehicles based on multiple charging guns.
[0061] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.
Claims
1. A power distribution device, characterized in that, include: One or two power conversion devices; The power distribution device includes M controllable switches, and each of the power conversion devices includes 9 power units; In the case of one power conversion device, M equals 12, and each power unit is connected to other power units through a controllable switch; in the case of two power conversion devices, M equals 24, and at least one power unit in one power conversion device is connected to a power unit in another power conversion device through a controllable switch.
2. The power distribution device according to claim 1, characterized in that, When there is one power conversion device, the nine power units in the power conversion device respectively form a first fully enclosed ring path, a first inner ring path and a first outer ring path, and each power unit is connected to other power units through at most two power units; The first power unit, the second power unit, the third power unit, the ninth power unit, the eighth power unit, and the seventh power unit are sequentially connected to form the first fully enclosed ring path via a controllable switch. The seventh power unit is connected to the ninth power unit via a controllable switch to form the first external loop path; The fifth power unit is connected to the sixth power unit, the fourth power unit and the eighth power unit through a controllable switch to form a first sub-path. The sixth power unit is connected to the first power unit through a controllable switch to form a second sub-path. The fourth power unit is connected to the third power unit through a controllable switch to form a third sub-path. The first sub-path, the second sub-path and the third sub-path constitute the path within the first ring.
3. The power distribution device according to claim 1, characterized in that, When there are two power conversion devices, the two power conversion devices include a first power conversion device and a second power conversion device, and the first power conversion device and the second power conversion device have the same topology.
4. The power distribution device according to claim 3, characterized in that, The four power units in the first power conversion device are connected to the four power units in the second power conversion device via controllable switches, and each power unit is connected to other power units through a maximum of four power units.
5. The power distribution device according to claim 4, characterized in that, The nine power units in the first power conversion device and the second power conversion device respectively form a second fully enclosed ring path and a second inner ring path; Among them, the first power unit, the second power unit, the third power unit, the fourth power unit, the ninth power unit, the eighth power unit, the seventh power unit and the sixth power unit are connected in sequence through a controllable switch to form the second fully enclosed ring path; The fifth power unit is connected to the second power unit and the eighth power unit through a controllable switch to form the inner path of the second ring.
6. The power distribution device according to claim 4, characterized in that, The third power unit in the first power conversion device is connected to the first power unit in the second power conversion device via a controllable switch; The sixth power unit in the first power conversion device is connected to the sixth power unit in the second power conversion device via a controllable switch; The fourth power unit in the first power conversion device is connected to the fourth power unit in the second power conversion device via a controllable switch; The ninth power unit in the first power conversion device is connected to the seventh power unit in the second power conversion device via a controllable switch.
7. The power distribution device according to claim 1, characterized in that, The power conversion device includes multiple charging gun connection interfaces for connecting charging guns, and the number of charging guns is less than or equal to the number of power units.
8. The power distribution device according to claim 1, characterized in that, The power unit is an AC-DC conversion unit, used to convert AC power into DC power and output DC power.
9. The power distribution device according to claim 1, characterized in that, The controllable switch includes: At least one of contactors, relays, and / or solid-state switches.
10. A charging system, characterized in that, include: The power distribution device according to any one of claims 1-9, at least two power modules, a controller, and at least one charging interface, wherein the power distribution device is connected to the controller, each of the power modules, and each of the charging interfaces respectively, and the controller and the controllable switch are communicatively connected; The power module is used to convert AC power from the power grid into DC power and supply it to the charging interface; The controller is used to obtain the required power of each charging interface and generate scheduling instructions based on the connection relationship of the controllable switches in the power distribution device and the required power. The power distribution device is used to control the opening or closing of the controllable switch according to the scheduling command, so as to distribute the output power of each power module to each charging interface.