Capacity mutual-aid storage and charging system and control method thereof
Through the implementation of the capacity mutual benefit storage and charging system, the problem of large impact on the power grid of the charging pile on the power grid was solved, and the construction cost was reduced through the shared power distribution capacity, which improved the energy utilization efficiency and reliability of the system.
Patent Information
- Application Number
- CN202411865521.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-18
- Publication Date
- 2025-01-21
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
Existing charging piles have a great impact on the power grid and have high construction costs, especially after the increase in single pile capacity, the user's investment costs have increased significantly.
Adopt a capacity mutual benefit storage system, through the combination of AC/DC converter, qualifying switch, DC bus and charging pile to achieve the impact load of the combination of storage-filling piles, and sharing power distribution through the common DC bus Capacity, dynamic capacity increase, and reduce the configuration of specialization.
By flattening the load and shared power distribution capacity of the charging pile, the impact and construction cost of the grid is reduced, the input cost of the power distribution facilities such as dictatorship is saved, and the energy utilization efficiency and reliability of the system is improved.
Smart Images
Figure CN119341062A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of storage-charging integration, and in particular to a capacity mutual aid storage-charging system and a control method thereof. Background Art
[0002] As the penetration rate of new energy vehicles gradually increases, electric vehicles will become the second largest load after air conditioning load. Electric vehicles are a type of load with high power demand and low energy demand. For the power grid, the load of charging piles / stations is a scattered impact load. The overall power demand is small, but it requires a large amount of distribution facility capacity, and the investment economy is very poor. When the reported capacity of the charging station is less than 160kVA, it can be connected to a public transformer; when the reported capacity exceeds 160kVA, it needs to be connected to a dedicated transformer. With the continuous increase in the capacity of a single pile (typical value is 60kW), most of the charging pile loads are connected to dedicated transformers, resulting in a significant increase in user investment costs. Summary of the invention
[0003] The purpose of the present invention is to overcome the deficiencies in the prior art, provide a capacity mutual storage and charging system and a control method thereof, and solve the technical problems that the existing charging piles have a large impact on the power grid and have high construction costs.
[0004] To achieve the above object, the present invention is implemented by adopting the following technical solutions: In a first aspect, the present invention provides a capacity mutual storage and charging system, including an AC / DC converter, an outlet switch , DC bus and charging pile, the input end of the AC / DC converter is connected to the AC system, and the output end is connected to the output switch connected to the DC bus, and the input ends of the plurality of charging piles are all connected to the DC bus; the charging pile includes a switch ,switch ,switch ,switch ,switch , a high voltage DC / DC converter, a low voltage DC / DC converter, a charging unit and an energy storage unit; the switch One end is connected to the DC bus, and the other end is connected to the low voltage DC / DC converter, the high voltage DC / DC converter and the switch one end of the low voltage DC / DC converter, the high voltage DC / DC converter and the switch The other end of the switch and the switch connected to the charging unit and the energy storage unit, the switch Connected in series to the switch and the switch between.
[0005] Optionally, the low-voltage DC / DC converter adopts a 7 kW DC / DC converter, and the high-voltage DC / DC converter adopts a 60 kW DC / DC converter.
[0006] Optionally, a reactive power compensation device is integrated on the DC bus to reduce reactive power loss.
[0007] In a second aspect, the present invention provides a control method for a capacity mutual aid storage and charging system, using the above capacity mutual aid storage and charging system, the control method comprises: When the AC system capacity is insufficient, disconnect the outgoing line switch ; In response to any charging pile receiving a fast charging request, If the energy storage unit capacity of the current charging pile is sufficient, switch ,switch And switch Close, and put the energy storage unit and high-voltage DC / DC converter into use to supply power to the charging unit; If the energy storage unit capacity of the current charging pile is insufficient, a shared charging pile is selected, where the charging unit of the shared charging pile is not in a charging state and the energy storage unit capacity is sufficient; Switch the current charging station ,switch And switch Close the switch of the shared charging station and switch Close, and put the energy storage unit and high-voltage DC / DC converter of the shared charging pile into use to power the charging unit of the current charging pile; or, Switch the current charging station ,switch And switch Close the switch of the shared charging station ,switch ,switch And switch , the energy storage unit of the shared charging pile, the low-voltage DC / DC converter of the current charging pile and the high-voltage DC / DC converter are put into use to power the charging unit of the current charging pile.
[0008] Optionally, the control method further includes: When the AC system capacity is insufficient, disconnect the outgoing line switch ; In response to any charging pile receiving a slow charging request, If the energy storage unit capacity of the current charging pile is insufficient, a shared charging pile is selected, where the charging unit of the shared charging pile is not in a charging state and the energy storage unit capacity is sufficient; Switch the current charging station and switch Close the switch of the shared charging station ,switch ,switch And switch The energy storage unit of the shared charging pile and the low-voltage DC / DC converter of the current charging pile are used to power the charging unit of the current charging pile.
[0009] Optionally, the control method further includes: When the AC system capacity is sufficient, close the outgoing line switch ; In response to any charging pile receiving a slow charging request, the switch and switch Close, and use the low-voltage DC / DC converter to power the charging unit; In response to any charging pile receiving a fast charge request, the switch ,switch And switch Close, and put the low-voltage DC / DC converter and high-voltage DC / DC converter into operation to supply power to the charging unit.
[0010] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a capacity mutual storage and charging system and a control method thereof. On a single charging pile, the impact load of the charging pile is spread out by a storage-charging combination, thereby reducing the capacity of the power distribution facilities. On multiple charging piles, the power distribution capacity is shared by sharing a common DC bus, without the need to configure a dedicated transformer separately, thereby achieving the effect of dynamic capacity expansion, thereby saving the investment cost of power distribution facilities such as dedicated transformers. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Figure 1 It is a schematic diagram of the topological structure of the capacity mutual storage and charging system provided in an embodiment of the present invention. DETAILED DESCRIPTION
[0012] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.
[0013] Embodiment 1:
[0014] like Figure 1 As shown, the embodiment of the present invention provides a capacity mutual storage and charging system, including an AC / DC converter, an outlet switch , DC bus and charging pile, the input end of the AC / DC converter is connected to the AC system, and the output end is connected to the output switch Connected to the DC bus, the input ends of multiple charging piles are connected to the DC bus; the charging pile includes a switch ,switch ,switch ,switch ,switch , high voltage DC / DC converter, low voltage DC / DC converter, charging unit and energy storage unit; switch One end is connected to the DC bus, and the other end is connected to the low voltage DC / DC converter, high voltage DC / DC converter and switch One end, low voltage DC / DC converter, high voltage DC / DC converter and switch The other end of the switch and switch Connect to charging unit and energy storage unit, switch In series with switch and switch between.
[0015] like Figure 1 As shown, in order to distinguish the switches in each charging pile, the switch in charging pile 1 is marked as switch ,switch ,switch ,switch ,switch , mark the switch in charging pile 2 as switch ,switch ,switch ,switch ,switch , until the switch in charging pile n is marked as switch ,switch ,switch ,switch ,switch .
[0016] Specifically, in this embodiment, the low-voltage DC / DC converter uses a 7 kW DC / DC converter, and the high-voltage DC / DC converter uses a 60 kW DC / DC converter.
[0017] The DC bus is integrated with a reactive power compensation device to reduce reactive power loss. The reactive power compensation device is integrated into the regulation of the DC bus. By adjusting the voltage and current in real time, it can reduce the reactive power loss of the system and improve the energy efficiency of the entire power grid. It plays a vital role, especially in application scenarios with high requirements for power quality. This power quality management method can not only optimize the system operation performance, but also reduce equipment aging and energy consumption loss, and improve the overall efficiency of the system.
[0018] Based on the above capacity mutual assistance storage and charging system, the embodiment of the present invention further proposes a control method thereof, including: (1) When the AC system capacity is sufficient, close the outgoing line switch ; (1.1) In response to any charging pile receiving a slow charging request, the switch and switch Closed, the low-voltage DC / DC converter is used to power the charging unit; at this time, the high-voltage DC / DC converter can charge / discharge the energy storage unit according to actual conditions.
[0019] (1.2) In response to any charging pile receiving a fast charging request, the switch ,switch And switch Close, and put the low-voltage DC / DC converter and high-voltage DC / DC converter into use to power the charging unit. Since the fast charging time is short, after the electric vehicle is fully charged, the energy storage unit can continue to be charged according to the actual situation.
[0020] (2) When the AC system capacity is insufficient, disconnect the outgoing line switch. ; (2.1) In response to any charging pile receiving a fast charging request, If the energy storage unit capacity of the current charging pile is sufficient, select the shared charging pile. The shared charging pile satisfies that its charging unit is not in the charging state and its energy storage unit capacity is sufficient; Switch the current charging station ,switch And switch Close the switch of the shared charging station and switch Close, and put the energy storage unit and high-voltage DC / DC converter of the shared charging pile into use to power the charging unit of the current charging pile; or, Switch the current charging station ,switch And switch Close the switch of the shared charging station ,switch ,switch And switch , the energy storage unit of the shared charging pile, the low-voltage DC / DC converter of the current charging pile and the high-voltage DC / DC converter are put into use to power the charging unit of the current charging pile.
[0021] (2.2) In response to any charging pile receiving a slow charging request, If the energy storage unit capacity of the current charging pile is insufficient, select a shared charging pile, which satisfies the requirement that its charging unit is not in a charging state and its energy storage unit capacity is sufficient; Switch the current charging station and switch Close the switch of the shared charging station ,switch ,switch And switch The energy storage unit of the shared charging pile and the low-voltage DC / DC converter of the current charging pile are used to power the charging unit of the current charging pile.
[0022] By sharing the distribution capacity, the investment cost of distribution facilities such as special transformers can be saved.
[0023] The capacity mutual storage and charging system provided in the embodiment of the present invention includes an AC / DC converter connected to the AC system, and shares the DC distribution capacity with the low-voltage / high-voltage DC / DC converter of the charging pile through the DC bus. Unlike the prior art, this system does not need to configure a dedicated transformer for each charging pile separately, but realizes dynamic sharing of distribution capacity through the AC / DC converter under the public transformer, thereby greatly reducing the equipment investment cost, especially the investment cost of the dedicated transformer and related distribution facilities. Through this topological structure, the control method provided in the embodiment of the present invention allows the power modules between the charging unit and the energy storage unit to be deployed with each other to realize capacity reuse. For example, when the charging unit is slowly charged, the idle DC / DC converter can be used to charge or discharge the energy storage unit, thereby achieving power balance of the storage and charging system and reducing the overall investment in primary equipment.
[0024] The capacity mutual storage and charging system can realize load transfer and hot standby functions between multiple substations through the coordination of multiple groups of control switches. In actual applications, if the load in a certain substation is too high, the energy storage system in other substations can transfer the excess capacity to this substation through the DC bus and control switches to ensure power supply stability; and when the system fails or the load fluctuates greatly, other substations can also respond as hot standby to improve the safety and reliability of the system.
[0025] In addition, since both the energy storage unit and the charging unit have DC characteristics, it has been calculated that the use of DC convergence and on-site consumption can save the loss of two-stage AC / DC conversion and distribution transformers, and improve energy utilization efficiency by about 5%. Therefore, in order to solve the problem of charging pile access occupying a large amount of distribution capacity, it is advisable to use energy storage as a solution and DC as a connection method to achieve flexible and friendly interaction with the power grid.
[0026] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.
[0027] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.
[0028] 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 technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.
Claims
1. A capacity mutual storage and charging system, characterized in that: Including AC / DC converter, outlet switch , DC bus and charging pile, the input end of the AC / DC converter is connected to the AC system, and the output end is connected to the output switch connected to the DC bus, and the input ends of the plurality of charging piles are all connected to the DC bus; the charging pile includes a switch ,switch ,switch ,switch ,switch , a high voltage DC / DC converter, a low voltage DC / DC converter, a charging unit and an energy storage unit; the switch One end is connected to the DC bus, and the other end is connected to the low voltage DC / DC converter, the high voltage DC / DC converter and the switch one end of the low voltage DC / DC converter, the high voltage DC / DC converter and the switch The other end of the switch and the switch connected to the charging unit and the energy storage unit, the switch Connected in series to the switch and the switch between.
2. The capacity mutual aid storage and charging system according to claim 1 is characterized in that: The low-voltage DC / DC converter adopts a 7kW DC / DC converter, and the high-voltage DC / DC converter adopts a 60kW DC / DC converter.
3. The capacity mutual aid storage and charging system according to claim 1 is characterized in that: The DC bus is integrated with a reactive power compensation device for reducing reactive power loss.
4. A control method for a capacity mutual storage and charging system, characterized in that: Using the capacity mutual aid storage and charging system according to any one of claims 1 to 3, the control method includes: When the AC system capacity is insufficient, disconnect the outgoing line switch ; In response to any charging pile receiving a fast charging request, If the energy storage unit capacity of the current charging pile is sufficient, switch ,switch And switch Close, and put the energy storage unit and high-voltage DC / DC converter into use to supply power to the charging unit; If the energy storage unit capacity of the current charging pile is insufficient, a shared charging pile is selected, where the charging unit of the shared charging pile is not in a charging state and the energy storage unit capacity is sufficient; Switch the current charging station ,switch And switch Close the switch of the shared charging station and switch Close, and put the energy storage unit and high-voltage DC / DC converter of the shared charging pile into use to power the charging unit of the current charging pile; or, Switch the current charging station ,switch And switch Close the switch of the shared charging station ,switch ,switch And switch , the energy storage unit of the shared charging pile, the low-voltage DC / DC converter of the current charging pile, and the high-voltage DC / DC converter are used to power the charging unit of the current charging pile.
5. The control method of the capacity mutual aid storage and charging system according to claim 4 is characterized in that: The control method further comprises: When the AC system capacity is insufficient, disconnect the outgoing line switch ; In response to any charging pile receiving a slow charging request, If the energy storage unit capacity of the current charging pile is insufficient, a shared charging pile is selected, where the charging unit of the shared charging pile is not in a charging state and the energy storage unit capacity is sufficient; Switch the current charging station and switch Close the switch of the shared charging station ,switch ,switch And switch The energy storage unit of the shared charging pile and the low-voltage DC / DC converter of the current charging pile are used to power the charging unit of the current charging pile.
6. The control method of the capacity mutual aid storage and charging system according to claim 4, characterized in that: The control method further comprises: When the AC system capacity is sufficient, close the outgoing line switch ; In response to any charging pile receiving a slow charging request, the switch and switch Close, and use the low-voltage DC / DC converter to power the charging unit; In response to any charging pile receiving a fast charge request, the switch ,switch And switch Close, and put the low-voltage DC / DC converter and high-voltage DC / DC converter into operation to supply power to the charging unit.
Citation Information
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