Modeling and design of a NOx emission reduction strategy for lightweight hybrid electric vehicles

This paper introduces a new forward-faced model for a lightweight urban series-parallel hybrid electric vehicle and an optimal control strategy for reducing fuel consumption and emitted pollutants of the vehicle. Utilized optimal control strategy for power management system of vehicle is designed based on equivalent consumption minimization strategy (ECMS). ECMS has been modified to include an SOC (state of charge) sustaining control and also a NO_x reduction control. A gear shifting control strategy in order to improve passenger feeling and vehicle performance during shifting has also been included in the system. Simulation results and effect of NO_x reduction control on fuel consumption and emissions have been illustrated.