Optimization of power train and control strategy of hybrid electric vehicles

This paper aims to optimize the transmission and control strategy of a parallel hybrid electric vehicle in order to minimize Fuel Consumption (FC) and emissions, simultaneously. Vehicle transmission is a Power Split Continuously Variable Transmission (PS-CVT), while the employed Torque Coupler (TC) is a two-speed TC. Using this type of TC increases designer ability to create a more ecient transmission. In this vehicle, the electric assist control strategy is used as the control strategy. In this strategy, the engine operates at optimal operation points, obtained using the Global Criterion method (GC). A multi-objective optimization is implemented using GC to minimize vehicle FC and emissions without sacricing dynamic performance. Finally, results of the conventional method of hybrid vehicle optimization and the results of using the Dynamic Programming method are compared