Dynamic Analysis And Control Of Shift Process For Automatic Transmission

With the development of the automotive industry as well as the improvement ofpeople’s living standards, Conventional Manual Transmission cannot meet people’sneeds and can adapt to the rapid development of automatic transmission. AutomaticTransmission is a typical automatic transmission, it can automatically change thetorque and speed, and has good self-adaptability to external load, also cansignificantly improve the performance of the vehicle starting and sexually. Therefore,it has an important significance to study the Automatic Transmission.This article relies on the project that cooperated by Jilin University incooperation with FAW Technology Center:AT control technology research. Select theAllison3500six-speed Automatic Transmission as the target, conducted a detailedstudy of the shifting process of the Automatic Transmission: first, build the model ofprocess shifting control, Secondly, it analyzes the common operating characteristics ofthe engine and the torque converter, then do the dynamic analysis of the shift processof the Automatic Transmission shift, finally, simulate the process of this transmissionof a file up to the second file and also do the experiment.(1)Select the Allison3500six-speed Automatic Transmission as the target, Buildthe process of shifting control model based on MATLAB/Simulink, including: theengine and the torque converter dynamic model, the friction clutch dynamic model,the process of a file up to the second file this transmission model and the dynamicshift control model.(2)Do the research about the Co-operating characteristics of engine and thetorque converter, first, analyze the engine operating characteristics; Secondly analysisof the torque converter operating characteristics, which includes originalcharacteristics and outside characteristics; finally, analysis the input characteristicsand output characteristics.(3)First do a detailed introduction to the lever method, use the lever method to dothe dynamic analysis of automatic transmission of a file up to the second file,which includes do a analysis about the torque phase and the inertia phase as well as stressanalysis in each shift process, then get the transmission output fluctuations torque offirst generation, second generation and third generation; And then through the clutchhydraulic pressure control and the engine control, to achieve a constant control of thetransmission output torque, to eliminate the fluctuation of the transmission outputtorque, to reduce the shift shock, and ultimately improve shift quality.(4)Finally, simulate the process of this transmission of a file up to the second fileand also do the experiment. first, the first generation of transmission, i.e. there is noengine control, and the simulation process in the transmission input torque is constant;Secondly the second generation transmission, do the engine torque control, in order tochange the transmission input torque; Finally, the third-generation transmission, dothe engine torque control and eventually eliminate output torque fluctuation of thetransmission and reduce shift shock and improved shift ride.Last, use the bench test todo the experiment about the process of a liter second gear.