Optimization Of Powertrain And Study On Vehicle Control Strategy For A Parallel Hybrid Electric Vehicle

Parallel Hybrid Electric Vehicle(PHEV) is link up the engine and the electric motor to powertrain by machinery.For different work patterns,the engine and electric motor are supplying power each other or together.The powertrain structure characteristic of PHEV,make powertrain parameter optimizing matching and the control strategy choice,become the key technology improving energy saving and environmental protection functions.In this thesis,the powertrain parameters optimizing methods and the control strategy of a PHEV have been analysed and studied.The dissertation introducing the classification and structure of Hybrid electric vehicle powertrain at first,and Respectively,made a detailed analysis and examples in series,parallel and combined structure of Hybrid Electric Vehicles.Inroducing the structure of a PHEV's powertrain unit,and described it's operating conditions.Based on analysis power system components of the a PHEV,the mathematical models of engine and electric motor have been built by Steadystate experimental data.Built powertrain optimization mathematical model used vehicle dynamics theory,Determine the design variables,target functions and constrained conditions about optimization.Changed the optimization model to computer procedure,run the procedure and obtain the optimal results.Results of optimization are showed that the optimal method maintained the original vehicle design Dynamic performance and enhance the entire vehicle fuel economy.Analysis of the current PHEV control strategy,puts forwards that uses the fuzzy logic control as the PHEV's multi-energy control strategy.Selected the difference between target engine torque and required torqueâ–³T and SOC of power battery as input parameters,take the minimum engine fuel consumption model as target designing the fuzzy control rules,to design The PHEV's fuzzy controller.The Reality of the PHEV Modeling Based on MATLAB/SIMULINK and ADVISOR Second Development Through ADVISOR interface realization of a fuzzy controller for control of the vehicle model..Use CYC_EUDC_LOW and CYC_UDDS to be in progress to a PHEV model simulating,The results show that compared to using the electric power-assisted control strategy,it can increase the Dynamics performance and Fuel Economy by using fuzzy control strategy,and the total efficiency of vehicles has improved obviously.