Research On Intelligent Control Methods Of Hybrid Electric Vehicle

Hybrid electric vehicle (HEV) is a new environment protected vehicle. It is droven by engine and electromotor together. By controlling the energy distribution between engine and electromotor, and making engine always work high efficiently, its petrol consumption and tail gas emission can be reduced. HEV need not build any auxiliary, and the requirement of its battery capacity is not high, so it can be industrialized easily. The research of this dissertation is supported by "Hybrid Electric Light Sport Utility Vehicle", the key program (Program ID: 02GKY1003) of "Tenth-five Science and Technology Proposal" in Hunan province, to research the intelligent control methods for HEV and improve its performance. The main research work of this dissertation includes:(1) The whole design targets of the designed CFA6470HEV HEV are introduced at first. This HEV is designed as a light SUV, and its design targets include: using four-cylinder engine and electromotor to obtain the performance of six-cylinder engine, petrol consumption lower than traditional four-cylinder vehicle at least 30% , and tail gas emission lower than European II standard 30%. Under these targets, the whole design scheme of CFA6470HEV HEV is given. In this scheme, the chassis, driving structure, and components of CFA6470HEV are selected, its whole layout and control scheme are designed, the control signals of each component are analyzed, the information flow chart are drawn, and the CAN control network of the whole vehicle is designed.(2) Energy management technology is the key technology in HEV control. It can influence the drive performance and environment protection performance of HEV directly. An intelligent HEV energy management system is designed in this dissertation to improve energy management performance of HEV. Its work principles are described, and its energy distribution strategies are researched. According to the orders of driver, the status of batteries and vehicle, these strategies can improve the power of HEV and reduce its tail gas emission by distributing the power of engine, driving motor and starting motor optimally. For prolonging the life of batteries, a fuzzy charging control method is proposed. For realizing the designed intelligent energy management scheme, the software and hardware are designed by using TMS320LF2407A DSP.