Configuration Analysis, Parameters Matching And Research On The Optimal Control For The HEV Equipped With DCT

In the process of automobile development, hybrid plays an irreplaceable role. It’s thefocus of our research that how to make a hybrid do more contribution for energyconservation and emissions reduction in their life stage. Because the DCT has nointerruption of power while shifting, high transmission efficiency, small volume weight andmany other advantages, it has been widely used. DCT hybrid cars had been researched byour team cooperation with relevant enterprises earlier. But summary of the configurations isnot comprehensive. Although the logic threshold control strategy can meet the basic designobjectives, the efficiency of power system was not ensured and the capability ofenergy-saving could not be brought into full play. Faced with these problems, on the basisof previous research, this paper will carry out the following researches:This paper will summarize the DCT hybrid configuration more comprehensively.According to different motor layout schemes of hybrid transmission system based on doubleclutch transmission, the DCT HEV will be classified to10configurations. And thefeasibility, characteristics, functions, configuration evaluation (Include the complexity toachieve function of HEV, the application range of the motor, the complexity to implementschemes, and engineering changes.) of every scheme will be made. Two schemes will beselected considering the business requirements. The working principle of the two schemesin each hybrid mode will be analyzed.The parameter of main components will be matched, including vehicle, engine, main/assistant motor, and battery. The power required of engine in different typical driving cycleswill be statistical analyzed based on Cycle Run. This paper will matching the motorparameter under the consideration of the motor working point. On the considering of merits and faults of all control strategy, the advantages of logicthreshold control strategy and instantaneous optimization algorithm were composited in thispaper, and using the instantaneous optimization algorithm to optimize and confirm thecritical threshold (Include the max speed of start and EV Mode when motor drive alone,The engine work lower limit when engine drive alone) of logic threshold control strategyand torque distribution. And will research on the transient process of clutch and enginestarting, confirm braking energy recovery control and shift schedule.To examine whether parameters matching and control strategy to meet the original designrequirements, co-simulations of CRUISE and SIMULINK were conducted. For twoconfigurations of the power performance and fuel economy will be conduct, and theirresults will be analyzed. To verify the new control strategy instantaneous optimized throughinstantaneous optimal method, the logic threshold control strategy, instantaneousoptimization control strategy and the logic threshold method based on instantaneousoptimization control strategy will be analyzed through simulation.Through the analysis of the HEV Equipped with DCT, we can arrive at three conclusions:(1) High frequency power area of engine (HFPE) based on Cycle Run has been obtainedthrough analyzing the engine. The distribution of HFPE is associated with engines and otherpower curve, and will be not affected by control strategies.(2) The parameter of motor acquired through considering of the motor working point, canmeet the vehicle’s performance requirements. And the simulation results prove thefeasibility of matching methods.(3)The logic threshold method based on instantaneous optimization control strategy canimprove the efficiency of components and the vehicle’s fuel economy further.