Modeling And Optimal Control Of Hybrid Electric Vehicle Transmission System

Energy crisis and environmental deterioration are two important problems of global development. The design of low energy consumption and low emissions vehicle can abate the pressure of energy absence and improve the quality of environment. Electric vehicle(EV) seems to be the best method to solve these problems, but its development is currently limited by battery's low energy density. And Fuel cell electrical vehicle(FCEV) is just on the laboratory level. On this occasion, hybrid electric vehicle(HEV) which combines the excellent performance of conventional vehicle(EV) with low mission and high efficiency of Electric Vehicle(CV) is invented, investigations on which become a new hotspot in international automobile field.The good way to deal with such a high complexity is to utilize mathematical models of the relevant processes. So, for complex hybrid electric vehicles, the quasi-stationary simulink models of the transmission system are built firstly, according to the kinetics equation and control-oriented mathematical model in this paper, which include vehicle body model, engine model, motor model, genetor model, battery model and gear box model. And these models are used in a systematic way.Then, for Parallel Hybrid Electric Vehicles(PHEV), a model-based strategy for the suboptimal control of parallel hybrid electric vehicles is presented, after the model of PHEV transmission system is built according to the configuration of PHEV transmission system. In order to get the fuel equivalent of the electrical energy, the equivalence factors have been driven. And the control splits the torque at the wheel axie between the fuel path and the electrical path, which minimizes the equivalent fuel consumption at each time instant. After that, the fuel economy on the MVEG-95 driving cycle is simulated. Compared with the conventional vehicle of similar dynamic performance, the fuel economy of the parallel hybrid electric vehicle increase above 30%, and the deviation of SOC is kept at a low level, which fully prove the validity of the control strategy.Finally, After the model of series hybrid electric vehicles transmission system is built, a real-time controller for the energy management of series hybrid electric...