Abstract: The basic principle of designing controller area network(CAN)-bus protocol is given. Considering the control characteristics of electric vehicles, the recommended network topologies of power train system are designed separately for three kinds of electric vehicles including hybrid electric vehicle, pure electric vehicle and fuel cell vehicle. Due to the disagreement on designing the application layer protocol of electric vehicles at present, a general protocol is proposed based on J1939, which can be applied on the power train system of hybrid electric vehicle, pure electric vehicle and fuel cell vehicle, etc. Meanwhile, the protocol is also compatible with conventional vehicle power train. Considering the topologies and control parameters of three kinds of electric vehicles sufficiently, and taking full advantage of CAN bus communication, the nodes’ source address, output parameters and parameter groups are all defined clearly in the general protocol. Under the baud rate of 500 kb/s, the protocol is validated through the experiments in both CANoe and hardware-in-the-loop platform which has been independently developed. The result shows that the communication performance fulfills the real-time requirements for control.

Key words: Application layer, Communication protocol, Fuel cell vehicle, Hybrid electric vehicle, Power train system