Design And Modeling Of A Multi-mode Drivetrain For Hybrid Electric Vehicle And The Building Of Simulation Platform

The hybrid electric vehicles can take advantage of the mature technology of conventionalcars and the energy saving and environmental protection of the electric cars, so they areconsidered as the most promising new energy vehicles. And there are full-mixed type、rang-extended type and the plug-in type, and the good hybrid project is the premise ofimproving economy and performance.Cooperated with a car company, a novel multi-mode driving system is proposed. Theprogram can achieve both the torque coupling and the speed coupling. According to drivingconditions of the vehicles, a reasonable allocation of the engine, the main motor and powerassist motor ISG, to obtain good power and fuel economy. Through a reasonable powerallocation of the engine, the main motor and the assist motor ISG, the good power and fueleconomy can be obtained.(1) By comparing the advantages and disvantages of exiting technology, a novelpowertrain is proposed and the topology structure and the working mode are analyzed, theproposed project can achieve the pure electric mode, the range-extended mode, the hybridmode;(2) According to the functional requirements under different modes, the selection of keycomponents is made, and on this basis the parameters of the key components are matched. Inorder to closely verify the performance of the vehicle, the test data of the key components areachieved by the bench tese, and according to the achieved data the vehicle dynamics model isbuilt. In order to easily compared with the exiting various technology the simulation platformof hybrid electric vehicles is built;(3) By optimizing the engine optimal work region, based on the engine optimal workingregion the vehicle control strategy is presented, and on the basis of the built simulationplatform, the fuel economy and power performance of the vehicle is analyzed. Finallycompared to the mature Volt, and the simulation results show that its dynamic performancehas been improved significantly, the highest speed has been increased by37.5%, and the fuelconsumption has been decreased by24.8%;(4) During driving, the new progect must carry out the mode switch which can cause the shock, in order to effectively improve the car’s comfort, ride comfort and the vehicleperformance, the strategy that by using the electrical power to compensate the lack of poweris presented. By using the software of the Matlab/Simulink and Matlab/Stateflow, the modeswitch simulation model of the vehicle is built and the simulation results are analyzed afterthe dynamic coordinated control. And simulation results show that the dynamic coordinatedcontrol strategy proposed in this paper can effectively reduce the impact of the new hybridsystem generated during mode switching, and improve ride comfort of the vehicle.By the above research work, the new project has good availability and sophistication, andcan lay a good theoretical basis for the subsequent real vehicle development.