CN211869172U - A charging pile system for power dispatching in different areas - Google Patents

Abstract

The utility model discloses a charging pile system for electric power dispatching in different areas in the technical fields of electric power systems and automation and electric vehicles. The utility model comprises a VRB-BESS device for storing electric energy, and is connected with the VRB-BESS device for performing electric The control of charge and discharge, power conversion and the converter PCS that realizes bidirectional energy transfer between the DC energy storage battery and the AC grid can reduce the impact and impact on the distribution network. VRB‑BESS has flexible and convenient installation and construction time. Short, fast response, long life, low maintenance cost, etc. By considering the density and distribution area of charging piles, the use of shared or built-in VRB-BESS devices can meet the demand and save the investment cost of the energy storage system , Adopt the scheme of interconnection of charging stations to improve the reliability and safety of the whole system, which not only brings convenience to users, but also has minimal impact and impact on the power grid.

Description

A charging pile system for power dispatching in different areas

technical field

The utility model relates to the technical fields of electric power systems, automation and electric vehicles, in particular to a charging pile system for dispatching electric power in different areas.

Background technique

With the increasing shortage of energy, electric vehicles have attracted great attention from countries around the world for their environmental protection and low-carbon advantages. Therefore, in recent years, the number of electric vehicles has shown a trend of rapid development. At the same time as the development of electric vehicles, their large-scale access to the distribution network for charging also has a certain impact on the power system.

Generally speaking, electric vehicles are usually charged in a trough or free charging mode. Load trough charging means that users charge electric vehicles during the trough period when electricity prices are low, while free charging means that users are not subject to any restrictions and can be charged at any time. Usually car owners start charging when they get home. According to statistics, the charging time usually occurs around 18:30, but this charging time is during the peak period of daily electricity consumption, which makes the peak-to-valley difference larger. In order to avoid this problem, the policy of time-of-use electricity price is adopted today, and users are encouraged to charge during the low load period. However, as the number of electric vehicles continues to increase in the future, when large-scale vehicle owners will charge at the moment of low electricity price at the same time Charging will cause a new round of peaks in the trough period, and this approach not only reduces the income of the power grid company, but also brings great inconvenience to users.

The number of electric vehicles will definitely be on the rise in the future. When every household has an electric vehicle, in order to facilitate the charging of users, the charging pile is no longer limited to a certain area, but every community, business district and other places will be equipped with electric vehicles. There are plenty of charging stations. If each charging pile is equipped with an energy storage system, it will inevitably increase the investment cost and maintenance cost of the grid company.

With the continuous development of electric vehicle charging piles with energy storage systems, when a user charges an electric vehicle during a peak load period, if the energy storage device in the charging station system in the area has no excess power, but the user urgently needs to The charging of electric vehicles will certainly have a certain impact and impact on the distribution network while meeting the needs of users.

At present, the existing technologies commonly used in the industry are as follows: using energy storage devices to realize high-power fast charging of electric vehicles, realize buffering between the distribution network and charging piles, reduce short-term interference and impact on the distribution network, and solve At present, the problem of relatively large harmonic content on the charging network side of electric vehicles has greatly improved the efficiency and safety of charging.

To sum up, the existing problems in the prior art are: only considering the problem of reducing short-term interference and impact on the distribution network and improving the power quality of the electric vehicle charging pile network side by configuring the charging piles of the energy storage device, and not considering the problem. Considering the economic problem of the charging pile equipped with the energy storage system and when the load peaks, the energy stored in the energy storage system in the charging pile is not enough to provide electric vehicle charging, and the impact on the distribution network when it needs to be powered by the grid The specific description of the existing problems is as follows:

(1) As the number of electric vehicles continues to increase in the future, when large-scale vehicle owners are charging at low electricity prices at the same time, there will be a new round of peaks during the trough period, and this approach will not only reduce the income of power grid companies , which brings great inconvenience to users;

(2) There are a large number of charging piles in each community, business district, etc. If each charging pile is equipped with an energy storage system, it will inevitably increase the investment cost and maintenance cost of the power grid company;

(3) With the continuous development of electric vehicle charging piles with energy storage systems, when a user charges an electric vehicle during a peak load period, if the energy storage device in the charging station system in the area has no excess power, but the user There is also an urgent need to charge electric vehicles. While meeting the needs of users, it will certainly have a certain impact and impact on the distribution network.

Based on this, the utility model designs a charging pile system for power dispatching in different areas to solve the above problems.

Utility model content

The purpose of the present invention is to provide a charging pile system for power dispatching in different areas, so as to solve the problems raised in the above background technology.

In order to achieve the above purpose, the present utility model provides the following technical solutions: a charging pile system for power dispatching in different areas, including a VRB-BESS device for storing electrical energy, and connecting with the VRB-BESS device for charging and discharging The converter PCS that controls, converts power and realizes bidirectional energy transfer between the DC energy storage battery and the AC power grid, the VRB-BESS device for storing electrical energy includes a charging pile box, and the charging pile box A charging pile power supply is installed in the inner cavity of the charging pile box, a support baffle is laterally welded to the inner cavity of the charging pile box, and the support baffle is arranged above the charging pile power supply, and a VRB-BESS device is placed on the top of the support baffle , the electrical input end of the VRB-BESS device is connected to the electrical output end of the charging pile power supply through wires, and the input and output ends of the VRB-BESS device are connected to the input and output ends of the converter PCS through wires, so The VRB-BESS device is an existing battery assembly with an all-vanadium redox flow battery as the core, the converter PCS is composed of a DC/AC bidirectional converter and a control unit, and the converter PCS controller receives through communication The background control command controls the converter to charge or discharge the battery according to the size of the power command to realize the adjustment of the active power and reactive power of the grid. The PCS controller of the converter communicates with the BMS through the CAN interface to obtain the battery pack. The status information can realize the protective charging and discharging of the battery and ensure the safe operation of the battery.

An electric vehicle charging pile with VRB-BESS devices in different areas, so as to satisfy the charging of electric vehicles and minimize the impact and impact on the distribution network. The utility model patent scheme proposes to use multiple charging piles to share a VRB-BESS device according to the location of the charging piles and the density of the number of charging piles, or directly use VRB-BESS for charging stations with only one charging pile in the area. The BESS device has a built-in energy storage system (piles-storage integrated type), which greatly reduces the cost and operation and maintenance costs of the power grid company to configure the energy storage system for electric vehicles; When there is no excess power and it is in the peak load period, in order to avoid the impact and impact on the distribution network, in the case of not directly using the distribution network to supply energy, call other charging stations that have sufficient power and do not need to charge The energy storage system powered by the pile supplies power to the charging station that lacks electricity, so as to solve the user's charging of electric vehicles.

The utility model is realized in this way, the energy storage device adopts VRB-BESS device, and the configuration scheme of the VRB-BESS device is specifically planned by the area involved in the charging pile. The above-mentioned electric vehicle charging pile configuration device with VRB-BESS device adopts a mode in which several charging piles share one VRB-BESS device in a commercial area with dense traffic, a tourist area and a residential area with dense electric vehicle users, The VRB-BESS device is connected to the bus where the charging pile group is located through the power line, so that the power distribution network can supply power to the charging pile and the VRB-BESS device during the load trough period, and the energy storage system can supply power to the charging pile during the load peak period. ; In areas where the flow of people and the number of electric vehicle users are not dense, the VRB-BESS device has a built-in charging pile mode, and the VRB-BESS device is connected to the charging pile through the power line, but it is embedded in the charging pile. During the low load period, the VRB-BESS device of the charging pile is charged; when the load peaks and the user needs to charge the electric vehicle, the electric energy stored in the device is used to supply the charging pile to charge the electric vehicle.

The charging stations in the area will be established as a cooperative alliance of charging station groups, so that the charging stations of VRB-BESS with surplus power and the charging stations with insufficient power are connected through power lines and communication lines to complement energy. When the amount of electricity stored in the VRB-BESS device in a charging station is insufficient, but it is also the peak period of electricity consumption, in order not to affect the normal charging of users and cause great impact and impact on the operation of the distribution network, the The cooperative alliance of the charging station group connects the smart meter to the VRB-BESS device and the bus side connected to the charging pile respectively through the power line, and uses the smart meter to obtain the measurement value of each VRB-BESS in real time. And the smart meter is also connected to the regional control center through a cable line, and the real-time measurement value measured by the smart meter is transmitted to the regional control center for processing. The measurement values of smart meters are processed and analyzed by a data management system and an automatic data collection system. After analyzing the real-time data measured by the smart meter, the electric energy dispatching system will call the adjacent charging station with sufficient energy storage capacity to supply the energy storage system of the charging station with sufficient energy storage capacity. capacity, stop supplying power to it.

The utility model discloses an electric vehicle charging pile configuration and an interconnection scheme of a charging pile system containing an all-vanadium redox flow battery energy storage system (VRB-BESS) in different regions. In this scheme, electric vehicle charging piles in different areas adopt different configuration schemes. For residential areas and commercial areas with dense charging piles, in order to reduce the configuration cost, several adjacent charging piles share a VRB-BESS device. For the case where the charging piles in other areas are not concentrated, the VRB-BESS is built into the charging pile; and the charging piles in the area are arranged as long as one or several charging piles contain a VRB-BESS device. As a small charging station system, it is divided into several small charging station systems, and finally the charging station systems are interconnected and connected to the distribution network. The invention can effectively reduce the interference and impact on the operation of the distribution network when the electric vehicle is charged; through the configuration planning of the energy storage system in different areas, the configuration cost and the operation and maintenance cost of the energy storage system are reduced; the interconnection of the charging station system can improve the System reliability and economy during electric vehicle charging.

Compared with the prior art, the beneficial effects of the present utility model are:

(1) It can reduce the impact and impact on the distribution network. In the case of the continuous increase in the number of electric vehicles in the future, there is no need for large-scale expansion of the distribution network;

(2) VRB-BESS has the advantages of flexible and convenient installation, short construction time, fast response speed, long life, low price of materials used, low maintenance cost, etc., and is more practical;

(3) By taking into account the density and distribution area of charging piles, a shared or built-in VRB-BESS device is adopted, which saves the investment cost of the energy storage system while meeting the demand;

(4) Using the scheme of interconnecting charging stations, through timely metering, monitoring and scheduling, when the electric vehicle needs to be charged during the peak load period, the electricity in the adjacent energy storage system with surplus electricity is dispatched to the electricity-demanding charging. station, and when the electricity-demanding charging station reaches the required power, stop power supply in time. Such an interconnection scheme can improve the reliability, safety, and economy of the entire system, and bring convenience to users while having minimal impact and impact on the power grid.

Of course, any product implementing the present invention does not necessarily need to simultaneously achieve all of the above-mentioned advantages.

The comparison between this technology and the prior art is shown in the following table

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the accompanying drawings required for the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without creative effort.

Fig. 1 is the structural representation of the utility model;

2 is a schematic diagram of a VRB-BESS device of an access system provided by an embodiment of the present invention;

3 is a schematic diagram of a VRB-BESS device being connected to a power distribution network by multiple charging piles sharing one VRB-BESS device according to an embodiment of the present invention;

4 is a schematic diagram of a built-in charging pile of a VRB-BESS device being connected to a power distribution network provided by an embodiment of the present invention;

5 is a schematic diagram of the interconnection structure of a charging station group including a VRB-BESS device provided by an embodiment of the present invention;

FIG. 6 is a flow chart of the configuration and interconnection scheme of the present invention.

In the accompanying drawings, the list of components represented by each number is as follows:

1-Charging pile box, 2-Charging pile power supply, 3-Support partition, 4-VRB-BESS device.

Detailed ways

The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, rather than all the implementations. example. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

Referring to FIG. 1 , the present invention provides a technical solution: a charging pile system for power dispatching in different areas, including a VRB-BESS device 4 for storing electric energy, and a VRB-BESS device 4 connected to it for The converter PCS that performs charge and discharge control, power conversion and realizes bidirectional energy transfer between the DC energy storage battery and the AC power grid, and the VRB-BESS device 4 for storing electrical energy includes a charging pile box 1, a charging pile box The inner cavity of the body 1 is installed with the charging pile power supply 2, and the inner cavity of the charging pile box body 1 is transversely welded with a supporting partition 3, and the supporting partition 3 is arranged above the charging pile power supply 2, and the top of the supporting partition 3 is placed with VRB-BESS device 4, the electrical input end of VRB-BESS device 4 is connected to the electrical output end of charging pile power supply 2 through wires, and the input and output ends of VRB-BESS device 4 are connected to the input and output of converter PCS through wires terminal connection, VRB-BESS device 4 is an existing battery component with an all-vanadium redox flow battery as the core, the converter PCS is composed of a DC/AC bidirectional converter and a control unit, and the converter PCS controller receives the background through communication Control command, control the converter to charge or discharge the battery according to the size of the power command, and realize the adjustment of the active power and reactive power of the grid. The PCS controller of the converter communicates with the BMS through the CAN interface to obtain the status of the battery pack The information can realize the protective charging and discharging of the battery and ensure the safe operation of the battery.

FIG. 2 shows the simplified principle of VRB-BESS of the access system, including the VRB-BESS device 4 and the power conversion system (converter PCS), wherein the PCS is composed of power electronic devices. VRB-BESS is mainly used to store electric energy; PCS is mainly used to realize functions such as charge and discharge control, power conversion, etc., and to realize bidirectional energy transfer between DC energy storage batteries and AC power grid. When connecting to the grid, the converter system must meet the harmonics and grid-connected voltage fluctuations of the VRB-BESS device when the grid is connected to the AC grid. In terms of capacity selection, the converter system should be based on the basic capacity of VRB-BESS. Sufficient reserve capacity is reserved to meet the needs of high-power output in a short period of time when the grid load suddenly increases.

Configuration of electric vehicle charging pile with VRB-BESS device:

FIG. 3 shows the basic structural composition diagram of multiple charging piles sharing one VRB-BESS to access the distribution network according to the present invention, including several charging piles and one VRB-BESS device. Among them, VRB-BESS is connected to the busbar where several charging piles are located through power lines to supply power to the charging piles; it is connected to the distribution network through power lines to charge itself. When the load is in a low period, the power distribution network will directly supply power to the charging pile, and the distribution network can also provide power to the VRB-BESS device; when the load is in a peak period, the power distribution network will no longer supply power to the charging pile, but It is powered by the electric energy stored in the VRB-BESS device to the charging pile.

Figure 4 shows a schematic diagram of VRB-BESS built-in charging pile connected to the distribution network, including a charging pile and a VRB-BESS device. The VRB-BESS device is built into the charging pile. During the peak load period, the VRB-BESS device built into the charging pile is used to directly supply electric energy to the charging pile; when the load is low, it is directly charged by the distribution network. At the same time, the distribution network can provide power to the VRB-BESS device.

The clustered structure of multiple electric vehicle charging piles with energy storage systems simplifies the configuration:

Figure 5-6 shows a simplified diagram of the interconnection structure of a charging station group with VRB-BESS devices, including charging piles, VRB-BESS devices, smart meters, communication networks, regional control centers, automatic data collection systems, and dispatching network systems. composition. The present invention proposes to divide the charging piles in the area into several small charging station systems according to the principle that only one or several charging piles contain one VRB-BESS device as a small charging station system, and divide these charging stations into several small charging station systems. The systems are interconnected to form a charging station system group. Among them, the smart meter is used to measure parameters such as the power and power quality of the energy storage system according to the preset time interval; the data measured by the smart meter is transmitted to the regional control center in real time through the communication network; through the data management system and The automatic data collection system is used to process and analyze the measured values of the smart grid; through the dispatching network system, the electric energy in the VRB-BESS devices with surplus power in the charging station system is dispatched during the peak load period, and the VRB-BESS devices with insufficient power are distributed to the charging station system. . For example, during the peak load period, the power stored by the VRB-BESS device of the charging station system in Figure 5 cannot meet the use of the system. The charging station with sufficient power in the BESS device dispatches an appropriate amount of power to the power-deficient charging station system to meet the charging of electric vehicles during the peak load period. And in Figure 5, the busbar voltage is 10kV, and its coverage (the length of the busbar) is determined by the number of surrounding charging station systems and the actual situation. Figure 6 shows the flow chart of the configuration and interconnection scheme.

In the description of this specification, description with reference to the terms "one embodiment", "example", "specific example", etc. means that a specific feature, structure, material or characteristic described in connection with the embodiment or example is included in the present invention. in at least one embodiment or example. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The preferred embodiments of the present invention disclosed above are only used to help illustrate the present invention. The preferred embodiments do not describe all the details, nor do they limit the invention to only the described embodiments. Obviously, many modifications and variations are possible in light of the content of this specification. This specification selects and specifically describes these embodiments in order to better explain the principle and practical application of the present invention, so that those skilled in the art can well understand and utilize the present invention. The present invention is limited only by the claims and their full scope and equivalents.

Claims (4)

1. A charging pile system for power dispatching in different areas, comprising a VRB-BESS device (4) for storing electrical energy, and connected with the VRB-BESS device (4) for performing charging and discharging control and power conversion And the converter PCS that realizes bidirectional energy transfer between the DC energy storage battery and the AC power grid is characterized in that: the VRB-BESS device (4) for storing electric energy comprises a charging pile box (1), so A charging pile power supply (2) is installed in the inner cavity of the charging pile box body (1), and a support partition (3) is laterally welded to the inner cavity of the charging pile box body (1), and the support partition plate (3) is arranged Above the charging pile power supply (2), a VRB-BESS device (4) is placed on the top of the support partition (3), and the electrical input end of the VRB-BESS device (4) is connected to the charging pile power supply through a wire (2) is connected to the electrical output terminal, the input and output terminals of the VRB-BESS device (4) are connected to the input and output terminals of the converter PCS through wires. 2. A charging pile system for power dispatching in different areas according to claim 1, characterized in that: the VRB-BESS device (4) is an existing battery assembly with an all-vanadium redox flow battery as the core, so The converter PCS is composed of a DC/AC bidirectional converter and a control unit. The converter PCS receives background control commands through communication, controls the converter to charge or discharge the battery according to the power command, and controls the active power and power of the grid. The reactive power is adjusted, and the converter PCS communicates with the BMS through the CAN interface to obtain battery pack status information, and protect the battery for charging and discharging. 3. A charging pile system for power dispatching in different areas according to claim 2, characterized in that: the VRB-BESS device (4) comprises an electric vehicle charging pile, and the electric vehicle charging pile comprises several charging piles , a VRB-BESS device (4); wherein the VRB-BESS device (4) is connected to the bus bar where several charging piles are located through the CAN interface. 4. A charging pile system for power dispatching in different areas according to claim 2, characterized in that: the VRB-BESS device (4) has a built-in charging pile connected to the distribution network, and the built-in charging pile is connected to the power distribution network. The incoming and outgoing distribution network includes a charging pile and a VRB-BESS device (4), the VRB-BESS device (4) being built in the charging pile.

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