Simulation Study Of Dual Clutch Automatic Transmission Shift Quality

With the rapid development of electronic control technology,the car in the field of transmission has also achieved key results.DCT is a new type of transmission developed on the basis of an electronically controlled mechanical automatic transmission,which has a specific internal structure and improved control strategy.Its unique dual-clutch design,through the electro-hydraulic control system to control the clutch and clutch clutch work together to achieve the transmission of the gearshift process.DCT to ensure that the process of shifting power without interruption,improve the quality of gearshift.In addition,its structure is simple,easy maintenance,high transmission efficiency.Moreover,DCT can use the MT production equipment,has a good production inheritance,it is in line with China's national conditions,the development of China's transmission is of great significance.Based on the practical value and practical significance of DCT on China's automobile market,this paper studies the 6-speed wet DCT,and deeply studies the shift process and related content.The contents of the research are as follows:(1)Study the structure and working principle of DCT.The structure and performance of the dual mass flywheel torsional damper are analyzed.Compare and analyze the advantages and disadvantages of dry and wet DCT.Introduce the electronic control system and hydraulic control system of DCT.Analyze the process and power route of DCT.(2)Establish the simulation model of the engine and vehicle.Study the dynamic model of the DCT shift process.Analyze the low-order torque phase,the inertial phase and the high block torque phase in the process of shifting.Establish the simulation model of two clutch oil pressure changes,impact degree and sliding friction.(3)According to the law of shift of two parameters,the optimal dynamic shift law and the best economic shift rule are calculated,and the characteristics of shift law are established.Considering the impact degree and sliding function,The comprehensive evaluation index of the gearshift quality is established,and theoptimal evaluation index of the gearshift quality is obtained by simulation analysis of the second gear ascending three steps,and the optimal oil pressure change rule is obtained,and the simulation results are analyzed to verify the impact and slippage Mo Gong is a pair of contradictory evaluation indicators,while DCT in the shift process will produce parasitic power phenomenon.(4)Based on the fuzzy control theory,the shift control strategy is optimized.The DCT shift process with fuzzy control is simulated and the results of the optimized simulation are compared with each other.The simulation results show that the DCT shift process,The simulation results are optimized to achieve the obvious optimization effect,which eliminates the generation of parasitic power in the process of gearshift.It proves the rationality of the optimal shift strategy based on the fuzzy control theory and improves the change of the transmission Block quality.