The development trend of new energy vehicle electronic control technology and charging and swapping technology

1. Development trend of new energy vehicle electronic control technology

During the “Tenth Five-Year Plan” period, in the “three vertical and three horizontal” strategic layout of the technological development of the new energy automobile industry, it is clear that electronic control technology refers to a multi-energy powertrain control system. More than ten years later, with technological progress, the electronic control technology of new energy vehicles not only needs to complete the analysis and transmission of driver’s operation intention and the optimization control function of main circuit energy, but also extends to the control of electric auxiliary components and their energy use optimization management, vehicle level safety management control, network information management control, etc. Of course, with the application of smart cars and smart transportation technology, new energy vehicle electronic control technology will also enrich its connotations.

With the increasing functions given to new energy vehicles, the electronic control system gradually adopts high-performance special control core (high-performance microprocessor), and also adopts dual core architecture (32-bit main control system + 16/8-bit monitoring and diagnosis system). On the basis of standardized software architecture (AUTOSAR, OSEK system), it meets the needs of highly integrated information (CAN/Flexray+WiFi+mobile communication network).

2. Development trend of charging and swapping technology for new energy vehicles

There are three ways for electric vehicles to replenish energy: conduction, induction, and power exchange. At present, the most widely used technology is the conduction method, that is, a charger plus a charging gun. Charging power less than 5kW is slow charging, and greater than 5kW is fast charging (high-power charging), and fast and slow charging compatibility is the development trend. The charging interfaces of various electric vehicles on the market should be designed and manufactured in accordance with the AC and DC charging ports specified in GB/T 20234 “Connecting Devices for Conductive Charging of Electric Vehicles”, including hardware and charging protocols. However, the charging ports of some foreign brands are not compatible with Chinese standards (such as Tesla) and need to be further regulated. China’s charging interface standardization work closely cooperates with International Electrotechnical Organization IEC, International Organization for Standardization ISO, and Germany. China’s charging interface standard has been recognized by IEC/SO and Germany.

In order to achieve the goal of lightweight new energy vehicles, the on-board charging control should be integrated with the motor controller, so that by sharing the power electronic power module and the control module, the quality of the vehicle can be reduced and the cost can be reduced. High-efficiency electric energy conversion is a topic that should be considered in charging technology, especially the problem of charging efficiency under severe weather conditions (high temperature, high cold). Wireless charging is an inductive charging method, and high-power wireless charging (30~400kW) technology has been developed in the world. China has already organized the development of high-power wireless charging equipment for electric vehicles by relevant scientific research institutes, universities and enterprises, and has carried out demonstration operations on more than 10 bus lines across the country.

New energy vehicles are equipped with electricity storage capacity of several kilowatt-hours to tens of kilowatt-hours, and some buses are even equipped with electricity storage capacity of hundreds of kilowatt-hours. With the increase in the number of new energy vehicles, the impact of charging on the power grid is increasing. Charging behavior may cut the peak of the power grid, and may also supply power to the grid on a large scale and temporarily to fill the gap during peak power consumption, or to provide short-term power to the home. Therefore, the need for research on intelligent charging technology is very urgent. Intelligent charging technology can also be called V2G/G2V technology, that is, vehicle-to-grid and grid-to-vehicle. The former is the on-board power supply to supply power to the grid or home, and the latter is to absorb electricity from the grid. Taking into account the time-of-use ladder price of the power grid, users may benefit by supplying power to the power grid, and develop into a shared economic model through guidance and the application of scientific charging and discharging technology.