Research On Emissions Control For Chang'an Hybrid Electric Vehicle

In order to deal with the problems of energy shortage and air pollution, the development of economical and clean vehicle has been a trend of automotive industry. Hybrid electric vehicle (HEV) known as a type of economical and clean vehicle has been regarded as a focus of development in the automotive industry. The region of engine's operation can be limited and controlled to reduce fuel consumption and emissions because of the action of electric system in the hybrid power system. Under the condition of fixed configuration and parameters, power can be distributed reasonably to let engine operate in the region of lower fuel consumption and lower emissions and control for fuel consumption and emissions can be realized by the control strategy.In the dissertation, Chang'an HEV is researched. The theoretical research of emissions control for HEV is carried out and fuzzy logic control strategy aimed at controlling fuel consumption and emissions is designed。The main work is as follows:(1) The harm of pollutant (Hydrocarbon(HC),Carbon monoxide(CO),Nitrogen Oxide(NOx)), formation principles and impact factors, the basic methods of emissions control, the progress of emissions control technology of vehicle and the advanced technology adopted for emissions control in the marketed HEV is analyzed. The above analyses provide the theory for emissions control of my research object.(2) On the foundation of the tests of engine, Integrated Starter/Generator (ISG) motor and NiMH battery, numerical model of power system is built by dealing with test data. At the same time, mathematic model of emissions is introduced and numerical model of emissions is established by using the emissions data.(3) Based on the analyses for design requirements of control strategy and the research for the existing and mature control strategies of parallel HEV, fuzzy logic control strategy aimed at decreasing fuel consumption and emissions is presented and the block of control strategy is designed.(4) The performed emission test of Chang'an HEV is analyzed, then the emission characteristic on the steady and unsteady condition is studied and the corresponding control method is presented.(5) Based on the analysis of modeling process for ADVISOR software and combined with the researched actual vehicle, the simulation model of Chang'an HEV was accomplished by redeveloping ADVISOR. Weight select for the optimal torque of engine is simulated using the established model as well as the model is simulated by adopting different control strategies under the classic drive cycles.In a word, the theoretical analyses and simulation of emissions control for Chang'an HEV is carried out in the paper, which provides some theoretical reference for emissions control of other HEVs.