Distributed communication system design based on CAN bus for parallel-serial hybrid electrical vehicles

Distributed network system based on Controller Area Network (CAN) protocol has been widely applied into the vehicle industries. CAN communication protocol for the parallelserial hybrid electrical vehicles (PSHEV) has been designed in the paper. Real-time scheduling algorithms based on optimization periodic algorithm (OPA) with non-preemptive and preemptive scheduling are also proposed with an optimization goal function to decrease the delay time for sporadic tasks and increase the CPU utilization for a real-time controller. Then a kind of method of solving the OPA have been designed namely exhaust algorithm (EA). With a view to avoid real vehicles experiment failures in advance, it is necessary for us to make an experiment set-up to verify the validity of the CAN protocol designed and OPA for the PSHEV. So the related hardware circuits for testing CAN system have been made. Finally, communication experiments are made based on CAN protocol proposed above. The results show the CAN protocol and OPA scheduling algorithm for the PSHEV are valid, all messages can be transmitted and received efficiently and completely avoiding the occurrence of loss of messages in the process of communications in all nodes of the system and the optimized periodic tasks as a result of OPA scheduling algorithm can decrease the delay time for sporadic tasks and increase the CPU utilization for a real-time controller.