Research On Multi-objectives Optimization Of Energy Management For Hybrid Electric Vehicle

The hybrid electric vehicle(HEV)energy management optimization research is single-objective optimization about fuel economy,although some scholars' research on fuel economy and emissions by multi-objectives optimization,but the method belongs to the single-objective optimization in nature,at the same time,others performance is ignored such as drivability.But,HEV belong to nonlinear multi-objectives optimization problem in natural due to complicated in structure and power coupling among the various components,so traditional single-objective method and weighted multi-objectives optimization hardly reflect the real situation of each objective and achieve trade off control of HEV.This paper based on National Natural Science Foundation of China(Grant No.51305473),Project Funded by China Postdoctoral Science Foundation(Grant No.2014M552317),Foundation and Advanced Research Program General Project of Chongqing City,China(Grant No.cstc2013 jcyj A60007),Aiming at the imperfect of HEV multi-objectives optimization problems,a multi-objectives optimization model of HEV is established,research on HEV multi-objectives optimization problems and trade off control based on intelligent optimization algorithm,using a multi-objectives optimization algorithm for hybrid system optimization without weighted,and obtain a group of the Pareto optimal solution set.Then To deal with the optimal solution set for the optimal control surface(for the two objectives problem is curve,three objective problem is surface),which provide the basis for the real-time control,which is objective and foundation according to the multi-objectives trade-off surface at real-time control.The main research contents as follows:(1)Analysis of HEV energy management optimization research status at home and abroad,summed up the HEV energy management multi-objectives optimization problems,results that the necessity of fuel economy and emissions and drivability of the multi-objectives optimization,and prerequisites of multi-objectives trade-off control.(2)Using a parallel hybrid electric vehicle as the research objective,Analysis the main parts of the engine,motor,gearbox,et al,the corresponding simulation model is established,and analysis of the control strategy at current mainly used in hybrid electric vehicle,the simulation model of the hybrid electric vehicle multi-objectives optimization simulation necessity is established in Matlab/Simulink,and laying the foundation for the following simulate algorithm performance.(3)Research on multi-objectives optimization theory and according to the theory,establish energy management of hybrid electric vehicle multi-objectives optimization problem mathematical model,Aiming to fuel economy and emissions and drivability,the control strategy parameters and some of transmission system parameters which have great impact as the optimization objective,the power and charge balance constraints of HEV must meet as constraint,the multi-objectives optimization problem mathematical model of this paper is established.(4)Research on multi-objectives evolutionary algorithm theory,based on multi-objectives evolutionary algorithm then improved,aimed the problems of this paper,the HEV-NSDEA multi-objectives optimization algorithm established,and combined above simulation model simulated and analyzed.The results show that fuel economy,emission and drivability performance evaluation index are improved,and obtaining a group of the Pareto optimal solution set.(5)HEV trade off control surface is proposed based on the multi-objectives optimization problem,fitting the Pareto solution set by LOWESS method,obtained HEV multi-objectives trade off control surface.This method has a guide role in that problem.