| The car with double clutch automatic gear belongs to the category of mechanical transmission.This transmission mode is quite different from that of hydraulic torque converter.Because the dual clutch transmission is controlled by computer,in the process of transmission upgrade and downshift,it needs to send signals to the engine through computer,and then feedback to the computer through the engine,in order to complete the shift task.Therefore,it is very likely that the car will have accidental stall and acceleration in the course of driving.According to the problems of low speed and frequent start,bump,abnormal noise,low transmission efficiency and slow response in the process of full load and overload,the application of dual clutch hydraulic torque converter in car is studied in this paper.In order to verify the feasibility of the structure design of automatic transmission(DCAT)of double clutch hydraulic torque converter,three aspects are mainly studied in this paper.(1)Through the research of AT,DSG,AMT and so on,aiming at the existing problems in automatic transmission of automobiles,the mathematical model of DCAT is established.The whole structure of DCAT virtual prototype is simulated by SolidWorks software,and the simulation model of DCAT is established.The control principle of traditional hydraulic mode and mechanical transmission mode of DCAT virtual prototype is designed.(2)Using the software of MATLAB to simulate and analyze the control strategy of the shift law of DCAT virtual prototype.Based on the economic shift law and the dynamic shift law,the design method of the combined shift law is put forward,and the control parameters of the combined shift law are obtained by using the programming calculation of matlab.The performance of the three shifting laws is compared by simulation,and the performance of the combined shifting law is the best.(3)According to the principle of automobile transmission,each system and module of automobile are combined into a whole vehicle simulation model.Simulink software is used to simulate and analyze the three shifting laws of power,economy and combination,and three sets of simulation parameters of transmission output speed,fuel consumption rate and shifting control strategy are obtained respectively.The results show that the fuel consumption of 45 S is 61.68 ml when shifting gears with economical shifting law,93.41 ml when shifting gears with dynamic shifting law mode,and 89.99 ml when shifting gears with combined shifting law mode.Therefore,the combination shift law has achieved a good balance in both dynamic and economic aspects.(4)The research results show that DCAT has the characteristics of higher transmission efficiency,better economy and power,smoother driving and no impact in shifting.It solves the problems of gear stumbling and irregularity in current DSG transmission. |
PDF Full Text Request