The production and sales of new energy vehicles are “hot”, and the performance in the field of charging facilities is also very active. The field of charging piles is another important battlefield of the new energy vehicle industry chain. A keen capital swarmed in, “charging the ground” to build charging piles offline, and various charging APPs online. At present, the operation of downstream charging piles is ahead of schedule, which directly drives the upstream equipment manufacturing and has reached a short time.
Intelligent charging pile–the composition of intelligent charging pile
Take this solution as an example. Generally speaking, the overall system consists of four parts: electric vehicle charging pile, concentrator, battery management system (BMS), and charging management service platform.
General design requirements of intelligent charging pile
China has a vast territory, spans multiple temperature zones, and the natural environment is more complicated. In addition, charging piles often work in a strong electromagnetic environment, which puts forward higher requirements for the design of electric vehicle intelligent charging piles.
1.1 Can stand the test of multiple weather
As the global climate keeps warming, the probability of natural weather events is getting higher and higher, which has a serious impact on various sectors of society. For a smart charging pile, its external structure must have good sealing, so that water drops, rain, snow, etc. cannot enter the pile, so as to avoid circuit short circuit or system failure; the inside also needs to form a good air flow, so as to distribute in time Heat generated by components.
1.2 should have strong anti-electromagnetic interference capability
The electromagnetic environment is mainly a phenomenon of signal transmission interference caused by various electromagnetic induction. With the rapid development of wireless mobile communication technology, electromagnetic interference has become one of the more common phenomena. In view of the working environment with strong electromagnetic interference, when designing the electric vehicle intelligent charging pile, it is necessary to focus on the electrical layout to reduce the adverse effects caused by various electromagnetic interference and ensure that the electric vehicle intelligent charging pile can operate normally.
Design and implementation of intelligent charging pile
2.1 External overall structure and master control unit device
The electric vehicle intelligent charging pile is designed with a cross-covering process. The strength of the entire pile body meets the requirements of IP65 protection level, which can effectively prevent the penetration of water. In terms of the main body design, the electric vehicle intelligent charging pile uses galvanized steel sheet as the system hardware material. And in order to ensure that it can operate normally in wet, salt, fog and other environments, the car baking process is used, and a layer of protective paint film is coated on the surface; in the selection of components, considering the temperature difference in different regions, 6 A serial port and 16 IO interfaces connected with each control unit can initially meet the needs of use and monitoring work. In addition, the device can work normally in the industrial temperature range, greatly improving the operating efficiency of the master control unit.
2.2 Design and implementation of display and monitoring unit
The display unit is composed of an LCD display, a touch screen, an indicator light, and buttons. The user can select the appropriate service plan by touching the corresponding buttons on the screen through the LCD display and according to the charging requirements of his own electric vehicle. When the service is completed, the indicator light will immediately remind the user that the charging pile is in working condition. When charging is completed, the indicator light changes from red to green, prompting the user to complete the charging. The operating voltage of the system is 3.3VDC, the logic level is 0 ～ 3.3V, the display driving voltage is 5VDC, the operating temperature is 0 ～ 50 ℃, and the wide temperature is -25 ～ 75 ℃. The monitoring unit is mainly used to supervise the working state of the intelligent charging pile, including the collection of analog quantity, the collection of switching quantity and the control of the output. After the analog quantity is collected by the system, the corresponding information will be transmitted to the switch quantity collection unit, so as to provide the user with a charging quantity matching the charging demand; To facilitate the use of other users.
2.3 Design and implementation of intelligent charging pile software system
2.3.1 Main control module
The main control module can automatically match the best service plan according to the user’s charging consumption needs. After the customer confirms the service, the corresponding information will be passed to each hardware module, and then the charging will start. At the same time, the module can also collect various consumption information of the user, such as the implementation operation data and charging records of the intelligent charging pile.
2.3.2 Security module
Security module refers to the secure storage unit of the system, which is composed of key management unit, data encryption unit and decryption unit. When electric car users pay using IC cards, their personal information will be encrypted. In addition, the system software uses key management to prevent hackers from invading the system and improve the security of user information. It is worth noting that the decryption unit can automatically identify the user’s identity when the user swipes the card to check out, thus completing this transaction.
2.3.3 Electrical design
The anti-static design of the circuit mainly uses two-way transient suppression diode grounding to achieve anti-static protection of the communication line. In the connection between the internal control board and the external functional modules, electric energy measurement, touch display screen, wireless communication transmission module and master control unit are used.