Research On Automobile Light Control System Of Electric Vehicle Based On CAN Bus

The automobile light system is one of the important systems to guarantee the vehicle safety travel. The traditional automobile light control system adopts the independent control with the relay, and causes the excess of automobile wiring harness and the complexity of the routing. Thus the serious electromagnetic interference is induced, and the reliability of the system drops. Aiming at above problems, the automobile light of electric vehicle is taken as the control object, and a automobile light control system of electric vehicle is designed, by using CANoe, a network integrated development environment which is developed by Germany Vector Corporation. The system replaces the traditional wiring harness by CAN bus technology, reduces the failure rate of the automobile light and extends the life of the automobile light.In this thesis, the assembly system network topology of electric vehicle is designed, considering the characteristic of the 2-wheel drive electric vehicle. Taking SAE J1939 protocol as reference, a CAN bus communication protocol, applied to the assembly system of the electric vehicle, is put forward. In this thesis, the details of the protocol -making process is given, focusing on a definition of the message priority, the node source address, the group parameter number, as well as the protocol date.The thesis designs a automobile light control network of electric vehicles, and the network includes three nodes, namely the master node, the headlight node and the rear lamp node. The network is simulated by CANoe, and the simulation results show the rationality of the design.The thesis adopts a modularization thinking in designing software and hardware, and researches the electromagnetic compatibility of hardware system and the reliability of software. In view of the load characteristic of the automobile light, the smart power switch is used to enhance the system reliability. The design of hardware circuit and the corresponding software of the master node and the two automobile light nodes is efficiently completed, by the semi-physical simulation function of CANoe, then the automobile light control network based on CAN bus is realized.The design is carried out a detailed debugging, in the platform of the automobile light control system of the electric vehicle. The automobile light control system is tested by CANoe, and the test results indicate that the data can be transported at 250Kb/s baud rate stably, accurately and credibly.