Comprehensive Energy And Emission Management For Diesel Plug-in Hybrid Electric Vehicle

Plug-in hybrid electric vehicle(PHEV)has advantages of energy conservation and environment protection,making it a hot topic both in research institution and automotive industrial enterprise.Compared with PHEV equipped with gasoline engine,the kind of diesel engine has much higher efficiency and lower emissions.Under the demand of strict ‘Fuel Consumption and Emission Standard’,the performance should be elevated remarkably compared to the traditional vehicle.It also leads to a sophisticated control system and control strategy.In this paper,construction and principal of diesel PHEV equipped with dual-clutch is analyzed.Based on the fuel efficiency,this research consider the influence of emission factor.Based on the requirements of both efficiency and emissions,a dual-clutch PHEV vehicle dynamic model has established using MATLAB/Simulink software.This model includes major subsystems as driver model,diesel engine model,ISG motor model,battery model,transmission model and SCR model.Second,a rule-based vehicle control strategy,‘Charge depleting-Charge Sustaining’is build based on MATLAB/Stateflow software by finite-state machine.This control strategy define a whole work mode of PHEV,engine-mode,motor-mode,engine-motor-mode,charge-mode,regenerative-braking-mode,mechanical-braking-mode and parking mode.These modes consists of a PHEV basic working mode.The simulation results of this control strategy testify the correctness of PHEV dynamic model and the control strategy.Third,study emphasis on the PHEV fuel efficiency and emission performances.Powertrain dynamic characteristic is observed by SOC,which is one state variable from this control problem.The other state variable is SCR temperature,an important feature from after-treatment system.This paper uses two-states dynamic programming optimizing the object function,which has two weighting factors again with fuel consumption and emissions.Optimal control rules with a series of weighting factors under specfic driving cycle are deducted by the optimization and analyzed.Then the linear regression is applied to deal with these consequences to extract a PHEV rule-based control which can be used in reality..Finally,the real-time control strategy simulated in MATLAB/Simulink and the test result is compared with the result optimized by DP.The correctness of this real-timecontrol strategy should be testified by its comparison.