| As the global energy source and environmental issues become increasingly prominent, developing new low fuel consumption and low-emission vehicles has turned into the primary task of automobile industry. The Hybrid Electric Vehicle (HEV) which combines the advantages of the internal combustion engine vehicles and electric vehicles is one of effective ways to solve the energy shortage problems and improve the environment condition, which is also an important development direction for modern vehicles. As a new type of transportation with multi-energy sources, the design of parameters matching and control strategy for powertrain is the core technology of HEV and also an important means of improving the vehicle dynamic performance as well as economic performance. Therefore, it is necessary to make thorough and further research. This paper will study the operation features of various components in HEV powertrain deeply, based on which the theories and application such as the modeling method for HEV system, the powertrain parameters matching and vehicle control strategies have been studied.In order to analyze the operation features of various powertrain in HEV, solve the problems of HEV powertrain parameters matching in early developing period and provide one platform for the HEV control strategy, this paper will propose the method combining theoretical modeling and data modeling based on test, and analyze HEV system according to the powertrain structural characteristics of HEV. Aiming at the complex structure of the HEV system, the powertrain interface parameters are standardized so that the energy flow of the model becomes more clear, intuitive, and clarity, and it lays a foundation for the development of HEV control strategies and the study of powertrain parameters matching as well as its operation features. Through the simulation, the results are compared with experimental results from the aspects of vehicle power, economy and HEV powertrain working characteristics respectively.For the sake of solving the rational allocation problems for the power of engine and motor, which are the two main power sources in HEV, and analyzing the affection of different power distribution on power and economic performances of HEV, in this paper methods of theoretical calculation, driving cycle analysis, and simulation analysis are adopted to study the relations between powertrain parameters matching and the performances of vehicle power and economic characteristics. On the premise of meeting the vehicle power requirements, combined with the specific driving cycle, the key components'parameters of HEV are optimized to realize the optimal fuel economy and multi-objective optimization into a single objective optimization. On this basis, the principles and methods of HEV powertrain parameters matching are also done research on, which lay a foundation for the initial design of HEV and optimizing system parameters.For determining rational and effective control strategies for HEV, improving system efficiency and obtaining the optimal fuel economy, two main kinds of control problems are studied. On the basis of analyzing powertrain efficiency characteristics and kinetic equation, the control strategies of transmission shift and power system dynamic coordination are proposed, and also the simulation is conducted. Based on the analysis of rule-based energy management strategy and dynamic programming-based global optimal energy management strategy, fully considering the efficiency of electric drive system, the instantaneous optimal energy management strategy based on hybrid system theory is presented. Meanwhile, fuel consumption and powertrain operation characteristics are compared in different energy management strategy for HEV.The HEV control platform is designed based on TMS320F2812, and design schemes of control system hardware and software are proposed. In addition, the vehicle communication programs and the software implementation process of vehicle control strategy algorithm on this platform are also presented. Finally, an HEV prototype experimental study is conducted to verify the correctness and effectiveness of established simulation model as well as the vehicle control strategy.
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