Study On Auxiliary Power Unit System And Control Strategy Of Hybrid Electric Vehicle Based On CAN Bus

There are two serious problems against the continual development of Chinese automotive industry. Hybrid Electric Vehicle (HEV) is becoming a main branch of new type automobiles in the world because of its high fuel economy and low emission performance.Jilin University takes on one project of Tianjin Science and Technology Committee the development of engine matching and powertrain system of HEV, together with Automobile Technology Center of China. The author participated in tasks of developing the Auxiliary Power Unit(Engine-Generator set, APU for short) control system for hybrid electric vehicle, which include the development of CAN bus system, the APU controller's hardware and software. This thesis is about study of CAN network and development of the Auxiliary Power Unit. This paper includes several researches as follows:First of all, control area network application layer was designed for the control network of hybrid electric vehicle (HEV). Experimental results indicate that the CAN control system for the HEV powertrain is very reliable and has low network load and good real-time performance.Secondly, the thesis discussed the basic configurations and powertrain of series hybrid electric transit bus, brought forward methods to design and evaluate components parameters and control parameters, finished parametric design of hybrid powertrain according to performance index of SHEV.Thirdly, 80C196KB is employed as a main controller in this control system. The APU controller according to adopting the principle of modularization and perfect EMC design based on 16-bit microcontroller is designed. In software design, interruption technology, modularization problem as well as anti-interference design have been adopted. Therefore, the reliability of the APU control system has been effectively improved. In this paper, intelligence node of CAN bus is designed based on Intel 80C196KC and Intel 82527, which contains hardware design and software design.Finally, Considering the batteries charge—discharge balance and the engine fuel efficiency under the given driving cycle,it is presented the control strategy using fuzzy logic.The model of control strategy is based on ADVISOR2002 and is simulated under several driving cycles and different control strategies. This strategy can distribute the torque of the engine reasonably and can keep the balance of battery SOC.Combining the above researching with each other, A control area network application layer was designed for HEV .The thesis achieves the performance index of the APU controller, provided theoretic method to design and optimize the APU system of HEV further, and first bring forwad fuzzy control with fratal ,settled a foundation of the development of the HEV control system.