As a kind of green transport with broad development prospect, the popularity of electric vehicles will be exceptionally rapid in the future, and the future market prospect is also exceptionally huge. Under the background of global energy crisis and serious environmental crisis, our government actively promotes the application and development of new energy vehicles, and charging/changing stations, as an important supporting infrastructure necessary for the development of electric vehicles, have very important social and economic benefits. A campaign to build electric vehicle charging/changing stations has been launched nationwide.

The overall system consists of four parts: EV charging pile, concentrator, battery management system (BMS), and charging management service platform.

The control circuit of the electric vehicle charging pile (peg) is mainly completed by the embedded ARM processor. Users can self-service swipe the card for user authentication, balance enquiry, billing enquiry and other functions, and a voice output interface can also be provided to realise voice interaction. Users can select 4 charging modes according to the LCD instructions: including charging by time billing, charging by power, automatic full, charging by mileage, etc.

The EV charger controller and the concentrator use CAN bus for data interaction, and the concentrator and the server platform use wired Internet or wireless GPRS network for data interaction, and for security reasons, the power billing and amount data are encrypted.

The main function of the battery management system (BMS) is to monitor the working status of the battery (battery voltage, current and temperature), predict the battery capacity (SOC) of the power battery and the corresponding remaining mileage, carry out battery management in order to avoid over-discharge, over-charge, overheating and the phenomenon of serious voltage imbalance between single batteries, and maximise the use of battery storage capacity and cycle life.

The charging service management platform has three main functions: charging management, charging operation, and comprehensive query. Charging management provides centralised management of the basic data involved in the system, such as electric vehicle information, battery information, user card information, charging pile (bolt) information; charging operation is mainly for billing management of user charging; and comprehensive query refers to comprehensive analysis and querying of the data of management and operation.