Research On Amt Transmission Ratio Optimization And Shift Strategy Of Pure Electric Vehicle

The problems of air pollution caused by the shortage of petroleum energy and the emission of automobile exhaust not only affect our life,but also promote the development of energy-saving and emission reduction technology in automobile industry.Pure electric vehicles without emissions,are favored by people because of their high energy efficiency and simple and fast operation.In order to further improve the efficiency of driving motors and batteries,and increase the driving range of pure electric vehicles,pure electric vehicles have begun to develop into multiple gears.Studying the parameter matching and optimization of the pure electric vehicle power transmission system can improve the performance level of the pure electric vehicle,and has an important impact on the design and research of the vehicle.At the same time,through reasonable shift schedules,a pure electric vehicle equipped with transmission allows the vehicle drive motor to rotate within a ideal range through reasonable gear selection to improve the power and stability of the vehicle.Therefore,the vehicle-compatible automatic transmission system adopts appropriate control technology,which can greatly improve the driving performance of electric vehicles,make it have good maneuverability and practicality,and accelerate the industrialization process.Based on the analysis of domestic and foreign research results,the power transmission system of pure electric vehicle was matched,the model of driving motor was determined by theoretical calculation,and then the transmission ratio of the assembled two gear AMT was analyzed and optimized.Based on the analysis of basic shift control strategy and the characteristics of AMT of pure electric vehicle,a shift strategy based on Takagi-Sugeno fuzzy shift control was proposed.The main research contents are as follows:By analyzing the research status of electric vehicle transmission system of domestic and foreign,and comparing and analyzing the advantages of electric vehicle matching AMT,the purpose was to match a two speed transmission for a pure electric vehicle.According to the initial matching results,AVL Cruise simulation software was selected to build the vehicle model according to the structure of its transmission system.Then Cruise and professional multi-objective global optimization software Isight were used for joint simulation,and non-dominant sorting genetic algorithm with elite strategy was used to optimize the two-speed ratio of transmission of pure electric vehicle.Based on the formulation of two-parameter gear shift laws with optimal dynamic property and economy,the fuzzy control algorithm was introduced by analyzing the driver's behavior intention.Since the driver's intention,as a subjective consciousness,is uncertain and essentially reflects the driving experience,fuzzy reasoning can be used to identify the excellent driver's experience.Finally,a fuzzy shift rule based on Simulink control was developed,through the comparison and analysis of cruise/Simulink joint simulation results,it showed that the T-S fuzzy shift strategy has better power and economy.The control strategy designed and developed in this paper has certain reference significance for further study of pure electric vehicle transmission system.