According to the different charging methods of electric cars, electric car charging facilities can be divided into four types: charging piles, charging stations, swap stations, and charging stations.
①Charging pile function
The function of an electric car charging pile is similar to a gas dispenser in a gas station. It is a kind of “power-on” device. The DC charging pile is a high-efficiency charger. Car battery charging. Electric car charging piles have corresponding communication, billing and safety protection functions. Citizens only need to buy an IC card and recharge it, and then they can use the charging pile to charge the electric car.
Charging piles can be fixed on the ground or wall, installed in public buildings (public buildings, shopping malls, public parking lots, etc.) and residential quarter parking lots or charging stations, and can charge various types of electric cars according to different voltage levels, such as As shown in Figure 1.
The input end of the charging pile is directly connected to the AC grid, and the output end is equipped with a charging plug for charging electric cars. Charging piles generally provide two charging methods: conventional charging and fast charging. People can use a specific charging card to swipe the card on the human-computer interaction interface provided by the charging pile to perform operations such as the corresponding charging method, charging time, and cost data printing. When the charging pile is charging the electric car, the display screen can display data such as the charging amount, cost, and charging time.
In order to meet the needs of large-scale household electric car users for timely and convenient charging, the charging pile charging mode is the best choice. Install a certain number of smart charging piles and a small number of smart ground chargers in the private parking lots of residential quarters or commercial buildings. The charging piles provide 220V or 380V AC power interfaces to provide emergency charging services for electric cars. Charging piles occupies a small area and low construction cost, which is more suitable for supporting large-scale household electric car charging. According to different types of current, charging piles can be divided into AC charging piles, DC charging piles, and AC/DC integrated charging piles, and the corresponding charging methods are used to complete the charging of the on-board battery.
(1) The DC charging pile is commonly known as a “fast charging” device, which is fixedly installed outside the electric car. The input end of the DC charging pile is connected to the AC power grid. It has the function of a charger, which can monitor and control the state of the charged battery in real time. , DC charging pile can measure the charging power.
The input voltage of the DC charging pile adopts three-phase four-wire AC380V±15%, the frequency is 50Hz, and the output is adjustable direct current, which can directly charge the power battery of electric cars. The general charging power is 10 ~ 40kW, the charging time is 1 ~ 4 hours, and the area is not large (less than 1 ~ 2m2). Since the charging power is not large, the general power circuit can satisfy the use. Since the DC charging column adopts a three-phase four-wire system for power supply, it can provide sufficient power, and the output voltage and current can be adjusted in a wide range, which can meet the requirements of fast charging.
The DC charging pile has the functions of unattended, smart card consumption and regional network management, which is convenient for operation department management. When electric cars are running in the city, there are more opportunities to stop in the middle. At this time, it is also an opportunity to temporarily supplement electric cars. DC charging piles have a small investment, a small area, and a relatively easy power grid. Therefore, they can be installed in parking lots, office buildings, shopping centers, hotels, restaurants, tourist areas, streets with parking spaces, and communities.
(2) AC charging piles are commonly known as “slow charging” devices, which are fixedly installed outside of electric cars. The input end of the AC charging pile is connected to the AC power grid to provide AC power to the on-board charger of electric cars (that is, the charger fixedly installed on the electric car), and it also has the function of metering and charging. The AC charging pile only provides power output and has no charging function. It needs to be connected to an on-board charger to charge the electric car. The AC charging pile has the characteristics of small footprint and flexible layout.
AC charging piles provide single or dual 220VAC/380VAC output interfaces. The output power is generally 5kW (220VAC) /20kW (380VAC). The real charging power is restricted by the on-board charger. Generally, the on-board charging power of small electric cars is Between 2 ~ 3kW. In view of the low cost and convenient charging time, electric cars should be charged at night as a priority. Since most families in our country do not have their own garages, and private cables are not allowed outdoors, it is necessary to equip each electric car with an AC charging pile.
An electric car charging station refers to a site for charging electric cars, similar to the current gas station. The charging station should have at least two basic functions of supplementing energy (mainly electric energy) and providing maintenance services, and be equipped with corresponding professional and technical personnel to complete this work. In terms of infrastructure of charging stations, power input equipment (interfaces and cables), fast chargers, power output equipment (interfaces and cables), power battery performance testing and diagnostic equipment, special fire extinguishing equipment and electric car parts are required Wait. The charging station is mainly composed of driving lanes, charging areas, power distribution devices, charging devices, monitoring devices, etc. There are multiple chargers and multiple charging piles in the charging station, covering a large area. The fast charging and slow charging methods are electric The car provides electric energy and can monitor the status of chargers and batteries.
The charging station can be divided into four sub-modules according to its functions: power distribution system, charging system, battery detection system, and charging station monitoring system. There are generally two ways to charge electric cars at charging stations: ordinary charging and fast charging. Ordinary charging is mostly AC charging, and 220V or 380V voltage can be used. Fast charging is mostly DC charging. The main equipment of the charging station includes a charger, a charging pile, an active filter device, and an electric energy monitoring system.
The replacement station refers to the place where the battery of an electric car is replaced. When the battery of an electric car is dead, go to the power station, remove the battery from the car, and replace it with a fully charged battery, while paying the corresponding fee. Electric car swap stations can save owners of large amounts of battery purchases, and can solve the problem of too long charging time. However, due to the heavy weight of batteries, mechanical equipment must be used to replace them, and there are certain restrictions on the manufacture of electric cars, that is, they must be unified The battery standard has high requirements for infrastructure construction. The battery swap station provides users with battery replacement and battery maintenance services. The main equipment of the battery swap station is battery disassembly and installation equipment. The battery swap station has the characteristics of strong operation professionalism, shorter battery replacement time, and smaller area than the charging station. The replacement station uniformly charges and maintains the replaced batteries. The advantage of substation replacement is that it is fast, and users can get on the road after replacing the battery, which is faster than refueling.
④Charging and swapping station
The charging station for electric cars has the functions of charging station and station. The electric car charging and swapping station is a relatively comprehensive place for electric car energy supply. It has battery replacement and high-power charging equipment, which can perform ordinary and fast charging and fast replacement services for different types of car batteries.