Research Of Electric Vehicle's Scheduling Algorithm Based On CAN Protocol

The emergence of new energy vehicles to solve the problem of automobile exhaust pollution in a certain extent,but also brought new hope to the dwindling resources problem,so the electric car has become the new direction of our automobile industry,development.With the increase of the daily application of electric vehicles,the performance requirements of people are increasing.The complex structure of the control system in the car also affects the real-time performance,so the simplification of the network is also an important direction of the vehicle network.CAN bus itself is the field bus,its data communication performance is more reliable,so it can better meet the needs of the car network.However,the CAN bus protocol is a carrier sense multiple access(Carrier Sense Multiple Access with collision avoidance,CSMA/CA)with collision avoidance,and its disadvantage is that it can not satisfy the real-time of low priority packets.FTT-CAN bus protocol is an improved protocol based on CAN bus,and the performance of the network system is improved greatly.This paper is the main content of in-depth understanding of the FTT-CAN protocol,according to its own characteristics put forward the improvement method is to use the hybrid scheduling algorithm to improve the system response degree of scheduling and low priority messages,which improves the real-time performance,the specific operation is to send the information is divided into periodic and non periodic information the information in their respective phase synchronous phase and asynchronous transmission,and the use of earliest deadline first scheduling algorithm in phase synchronization in asynchronous phase using dynamic priority promotion scheduling algorithm.Short data frame and data frame priority classification and dynamic priority promotion combination,using short data frame and data frame classification for priority priority data frames are initialized,so it can improve the response to low priority information,and can increase the number of units of time to send data frames,so as to enhance the real-time of the whole network.We need experiments to prove that the improved protocol using FTT-CAN hasbetter real-time performance,so we can get the experimental results with the help of CANoe simulation environment.After several experiments,compared the results obtained by the data protocol respectively using the original CAN protocol and FTT-CAN,confirmed the FTT-CAN protocol in use with better schedulability and higher real-time.