Application of electronic control technology in modern electric vehicles

Application of electronic control technology in modern electric vehicles

Electronic control technology is widely used in modern electric vehicles, and the sharing of operating parameters of various equipment has become a feature of the vehicle system. The CAN bus has high data exchange speed and strong noise resistance, making it the first choice for internal vehicle communication networks. The functions and characteristics of the high-performance microprocessor P8xC592 with integrated CAN controller and its application in the auxiliary three-phase inverter power supply of electric vehicles are introduced.

Keywords: CAN bus P8xC592 microprocessor three-phase inverter power supply Each control command has a different priority, so a data exchange network with a priority competition mode is required, and it has an extremely high communication rate. In addition, as a manned transportation tool, electric vehicles must have extremely high operating stability, and the vehicle communication system must have strong fault tolerance and fast processing capabilities. Such as the car steering power pump, brake air pump, water pump in the cooling water cycle, and compressor in the air conditioning system. The working requirements of the three-phase inverter power supply are: independently maintain the stable operation of the auxiliary motor under normal operation, and be able to adjust the working state appropriately according to the instructions of the host computer; quickly relate to the output and shut down safely when the load fails (such as motor short circuit), and can report its own fault to the host computer and other nodes through the CAN bus, triggering related operations of various vehicle systems (for example: the human-machine interface display system located on the dashboard will immediately display a warning message, report the vehicle fault location, and prompt the driver to slow down; and the vehicle energy management system will issue a command to turn off the input of the auxiliary inverter power supply, and save the received error code and current operating parameters to facilitate maintenance personnel to diagnose faults). 1 Introduction to the P8xC592 chip
    · Two pulse width modulation outputs with a resolution of 8 bits include all the hardware necessary to achieve high-performance serial network communication, so that the communication flow can be controlled to pass smoothly through the LAN of the CAN protocol. In order to avoid confusion, the CAN controller added to the chip appears to the CPU as a memory image peripheral device that can work independently on both sides, that is, the P8xC592 can be simply imagined as an integration of two independent working devices. If the function of the CAN controller part is turned off, the chip can be used only as an ordinary 8-bit microcontroller with analog A/D conversion. 2 Hardware composition of the inverter power system 3 Software design of the inverter power system When the communication program is triggered, the CAN controller of the P80C592 performs related tasks according to the command word. When the host computer requests data, the various operating parameters of the inverter power are transmitted to the vehicle system; when the host computer queries the node status, the current CAN node status and other data are sent out; when the host computer requires modification of the operating parameters, the received data parameters are stored in the data memory.