The influence of the selection of engine point in operation based on the working condition identification on the overall fuel consumption

abstract：Response to the government's higher requirements for car fuel consumption and emissions the research, design and manufacturing of advanced hybrid engine has become a current hot topic。This paper starts with a comparative analysis of several hybrid powertrain and transmission mechanism technical schemes that have been applied or are still under study.Then, a mathematical model is established to optimize the parameters of the MAP diagram of hybrid engine to get the impact of different engine points in operation of hybrid engines on the overall fuel consumption under different Driving cycles, and model the best engine points in operation to achieve the goal of improving fuel economy.Through building the mathematical models and comparing the data arrival at the conclusion that:(1)Through the data analysis of the energy conversion efficiency and the cooperation relationship between the engine and the motor, the Mixed type power systems（SPHEV） can have more working mode and higher cost performance compared with the series hybrid electric vehicle（SHEV） and the parallel hybrid electric vehicle（PHEV).(2)Algorithmic optimization of the selection of engine operating point and motor  operating point in the Mixed type power systems（SPHEV） can Save about 6% of the fuel(There are deviations under different Driving cycles.)(3)Choosing the best working point facilitates the researchers' subsequent research on improving the fuel economy of Hybrid Powertrains.