The Design And Development Of Multi Mode Electromechanical Coupling System For Electric Vehicle

Our country is vigorously implement the strategy of development of new energy vehicles,plug-in hybrid electric vehicle is one of the main development direction of new energy vehicles,electromechanical coupling system directly affects the performance and fuel economy of plug-in hybrid electric vehicle.Plug-in hybrid cars on the market at present there is a power transmission system of engine fuel efficiency optimization and fixed speed reducer can not ensure the high efficiency of drive motor has been in the work area.In this paper,combined with the current provincial major r&d projects,to improve the existing plug-in try to power performance and fuel economy of hybrid electric vehicles as the goal,based on virtual prototype technology in all-electric mode have two gears transmission function of the new model more electromechanical coupling system.Thesis focuses on the system parameter design,structural development,virtual prototype modeling and simulation,the box body vibration analysis and optimization,etc.The main research content is as follows:The first chapter through the research background and hybrid research status at home and abroad,the comparative analysis on the market,several typical hybrid electric vehicle power transmission system,this paper discusses the importance of the electromechanical coupling system designed by this paper.The second chapter has carried on the system structure scheme design,according to the parameters such as vehicle,sending drive motor,planetary mechanism completed system,axial,synchronizer,reducer,differential parts parameters,such as design,bearing,cooler three-dimensional structure selection and system development and the two-dimensional drawing work.The third chapter using industry widely used mechanical drive system design software Romax has carried on the virtual prototype modeling,according to the maximum input torque of gear,shaft,bearing,body parts,such as static strength analysis,the results show that the parts safety coefficients above 1.8.The fourth chapter first use Hypermesh/Optistruct module for lightweight design of key parts,the optimized system total quality reduce 4.9 kg;Second gear with Romax micro modification,the optimized gear transmission error by 18.3%,and the load of unit length by 31%,improve the system stability.The fifth chapter first has carried on the box under the free modal,constraint modal natural frequencies and modal analysis,calculate the gear in the drive motor excitation frequency common speed range,improved the enclosure structure,avoid body appear low order resonance;Second on the system of pure electric drive mode of carrying gear on the sensitivity analysis of the factors which influence harshness(NVH)for a second set of system performance optimization design provides important guidance,at the same time using Romax knock vibration analysis for the simulation analysis of bearing gear on vibration simulation method provides a new software.