Study On Gear Shift Strategy For Dual Clutch Transmission Based On Driver-Vehicle-Environment

With the fast development of electronic control technology, increasingly more and moreperformance requirements to the vehicle are emerging. Automatic transmission has beengetting more attention by consumers. The main advantage of automatic transmission isreducing fuel consumption and improving emissions, there are a lot of traffic jam happenedeveryday in the most of countries, using automatic transmission can relieve fatigue of drivers.So it has been equipped in a lot of vehicles.Volkswagen achieved great success in the market of China, because of its TSI and DSGpowertrain strategy, so DSG is also called DCT has a good reputation. Dual clutchtransmission has two clutch based on manual transmission, using gear speed shift to transferpower, so It maintained advantages of a manual transmission：the simple structure and highefficiency. But TCU controls the shift progress,completed by clutch to clutch shifting,achieves automatic power shift without interruption, which has improved the vehicle’sdynamic property and economy.The gear shift schedule is one of the key technologies in the dual clutch transmissioncontrol system. In actual working condition, Moving vehicle is a complexdriver-vehicle-environment closed-loop system. However, the traditional shift schedule onlyworks in fixed mode, so the demands of different driver types、driving condition and driverintentions can not be satisfied. Therefor，the paper focused on gear shift strategy for dualclutch transmission based on driver-vehicle-environment and carried out the followingresearches:(1) The model of the entire powertrain is built used in DCT’s simulation using theMATLAB/Simdriveline. Build the driver model and controller model using modularmodeling technology. In addition, dynamic、economic and integrated shift schedules are builtbased on two-parameter shift schedule. (2) The paper study on the characteristics of pre-select gears and build the mathematicalmodel based on the working process of synchronizer. Then the paper build pre-select gearsshift strategy.(3) The paper proposes the method of quantifying driver type based on the driver powerdemand, and carry out the relevant real vehicle test. According to the driver type and itsthrottle opening threshold value, DCT shift schedule based on driver type is built, throughthe simulation, the shift schedule’s validity based on the demands of driver is verified.(4) The paper analyses the characteristics of driving on the congested road and problemof the traditional gear shift schedule for some intentions of driver, proposes thediscriminating methods, according to the result, modified the control strategies, the validityof the strategies are verified through the simulation result.