Research On Control Strategy And Simulation Analysis Of Plug-in Hybrid Electric Vehicle

The problem of environmental pollution and energy shortages are becoming more and more serious.As an environmentally-friendly vehicle that replaces traditional fuel vehicles,new energy vehicles are booming under the guidance and support of governments and the promotion of major automobile companies.Due to the popularity of charging equipment and the problem of range,pure electric vehicles have difficulties to promotion at this stage.The Plug-in Hybrid Electric Vehicle(PHEV)which combines the advantages of traditional fuel vehicles and electric vehicles has emerged.Its various working modes can adapt to a variety of travel conditions and driving needs.It has the potential to replace traditional vehicles and has strong research value.The thesis relies on the school-enterprise cooperation project ‘PHEV power system simulating calculation and optimization’as the research background.Based on a fuel SUV in the enterpriseas as the model prototype transformed into a three-motor plug-in hybrid vehicle.The target is making a productized control strategy,and to design the vehicle energy management control strategy,on the basis of ensuring the dynamic performance,the comprehensive fuel consumption is optimal and meets the design requirements of the enterprise.The main research contents include:(1)Based on the power system framework given by the enterprise,to design the PHEV power system of P1+P3+P4,and then determining the performance index according to the project requirements,and finally complete the parameter matching and selection of key power components.(2)According to the structural characteristics of the PHEV power system,the principles of the development of the control strategy and the characteristics of the main operating modes such as PHEV parallel and series are studied.By analyzing the static characteristics Map and efficiency curve of the power components,combined with the dynamic driving parameters such as vehicle speed and SOC and the actual engineering experience,the mode switching threshold is determined and the vehicle driving mode is divided.Finally,the energy management control strategy based on static logic threshold is designed,and the design of modular control strategy model is completed on MATLAB/Simulink software platform.(3)Build a vehicle structure model on the AVL Cruise platform to verify the power performance of the vehicle.Through the joint simulation of MATLAB/Simulink,the economic simulation and test are completed under NEDC conditions,and the average integrated fuel consumption per 100 kilometers is 6.19 L,which is 22.63% higher than that of the original fuel vehicle.(4)Using Isight5.5 platform and AVL Cruise integration optimization,using the non-dominated sorting genetic algorithm with elite strategy to optimize the economic and emission performance.Thought optimizing the parameters in the control strategy to obtain different power conditions for the optimal parameter value.The overall fuel consumption of the final 100 kilometers reached 6.05 L,which is 24.38% higher than the original car,and the emission performance improved by 5.28% before optimization.In the thesis,the combination of mathematical analysis and model simulation is used to design the vehicle dynamic system and control strategy,which not only meets the project design goals,but also obtains good research results.This provides a reasonable reference development for the plug-in hybrid vehicle control strategy,meanwhile it has engineering practical value.