Research On Control Technology Of Power Uninterrupted Gear Shift In Pure Electric Vehicle

With the increasingly serious problem of environmental pollution and energy shortage,energy saving and emission reduction has become a major solution.The traditional engine has the process of fuel combustion,which makes the vehicle emission become one of the main pollution sources.The development of new energy vehicles is an important way to solve the vehicle emissions,electric vehicles as a green car,has been more and more attention.In the national policy and the environment under the pressure,the pure electric vehicle technology has made rapid development.In consideration of cost and structure layout in pure electric vehicle at present,driving system mainly adopts the fixed ratio reducer,single gear cannot meet the driving requirements for automobile acceleration,climbing and overtaking.Multi gear transmission can solve this problem,but there are also problems of interruption of traction force in shift process,the driving comfort is reduced.Therefore this article put forward the new uninterrupted shift strategy,and bench experiments are verify by construction test system.Firstly,according to the requirements of vehicle performance,calculated parameters of the vehicle power system,determine the type and main parameters of motor and gearbox.Vehicle driving performance parameters were simulated in CRUISE software,including the maximum speed,acceleration time and climbing,the simulation results show that meet the requirements of the performance of the vehicle,to prove the matching parameters are rationality.The experimental bench is built which dual-motor AMT of drive system,the platform validity is verified by measuring test devices.Uninterrupted shift as the control target,put forward a dual-motor output torque coordination control strategy,and base model designed control strategy model in MATLAB/Simulink software.After building the experiment bench,the control strategy of the model is verified.The test results show that the dual-motor torque coordination control can reduce the speed fluctuation of the transmission output shaft during the shifting,and maintain torque transmission,verify the feasibility of dual-motor uninterrupted shift.Finally,making the driving cycle experiment of single motor two gear drive system,the energy consumption of cycle is calculated.Meanwhile the original shift curve was optimized using dynamic programming algorithm,this mean can improve the economic performance of the vehicle.