Performance Analysis Of Four-speed Automated Mechanical Transmission For Pure Electric Vehicles

Due to the enormous pressure brought by energy and environment,the development of new energy vehicles and the sustainable development of the automobile industry have become the mainstream of the times.Pure electric vehicles have become the focus of research due to their high energy efficiency,cleanliness,no pollution and zero emissions,and have broad market and application prospects.At present,there is still a lot of room for development in the transmission research of pure electric vehicles.The research work on the transmission of pure electric vehicles has a crucial role in improving the endurance of vehicles and the improvement of power performance.Taking the existing pure electric vehicle models on the market as the research object and formulating the vehicle performance indicators as an important indicator of power system parameter matching with reference to national standards,the selection and parameter matching of the motor and battery are completed.This paper analyzes the type and transmission mode of the planetary gear train and proposes a four-speed automated mechanical transmission structure based on the planetary gear train.This structure is characterized in that it does not require a synchronizer during the gear shift process.After analyzing the shifting process,specffic shifting control strategies and dual-parameter economic shifting rules were formulated.Aiming at the influence of the four-speed automated mechanical transmission on the performance of the vehicle,a vehicle model was built in the CRUISE software,and a single ratio reducer vehicle and two-speed automated mechanical transmission vehicle was used as an experimental comparison item to analyze its acceleration performance,climbing performance and cruising range.The simulation results verify the feasibility of the four-speed automated mechanical transmission matching the pure electric vehicle,and the economy and power of the pure electric vehicle are improved relative to the single ratio reducer and two-speed automated mechanical transmission vehicle.Build a shift control strategy model in MATLAB/Simulink,through joint simulation with CRUISE to realize the simulation analysis of transmission shift process and quantitative evaluation of shift quality.