Research On Controlling Strategies Of Vehicle Equipped With AMT In Starting Up Process And TCU

In each part of a automotive, the powertrain plays a key role in determining thedynamic performance, comfort, economy and reliability. The automated mechanicaltransmission (AMT) is mainly characterized by high efficiency, low cost, and beingeasy to manufacture and maintain, and so on. It is very difficult to control the carequipped with AMT in starting-up process, and the controlling effect, which isevaluated by starting comfort and rapidity, is a main factor that affects startingperformance. Researching on a new kind of controlling method that cancomprehensively consider driving comfort and vehicle dynamic performance issignificant for expanding the scope of application of AMT and reducing vehicleenergy consumption.This paper focused on clutch engagement controlling and engine speedcontrolling in the starting-up process. By analyzing the characteristic of powertraincomponents of automotive with AMT, a starting-up simulation model was established.In order to achieve the “fast, slow and fast" rules of clutch engagement, a new kind ofclutch engagement controlling strategy which was based on fuzzy control and self-adapting controlling method by studying the automatic clutch engagement control.The fuzzy controlling method was used to overcome the nonlinearity and uncertaintyof clutch controlling system. At the same time, a new kind of engine speed controllingstrategy was proposed to reduce the speed fluctuation, which was based on constantspeed controlling method, it was combined with the function of model modification ofself-tuning controlling method and the rapidity of PID controlling method. Asimulation model of the starting-up process was established to verify the clutchengagement controlling and engine speed controlling strategy. A new kind of AMTcontrolling unit, which took MC9S12XET256as microcontroller, was designed andmanufactured by studying the method of manufacturing the AMT controlling unit.Circuits of the function modules were designed and produced. By taking a car withautomated transmission as the experimental carrier, the feasibility of the proposedAMT controlling strategy was studied. Starting-up process with different openingdegree of accelerator was tested on the test platform. It was indicated that the AMTcontroller could not only fully execute the intention of the driver, but also ensurestarting comfort and small fluctuations of engine speed by data acquisition and curve fitting.This study provides valuable reference for the expansion of application range ofAMT in domestic automotive industry, as well as the improvement of the design levelof domestic automotive industry.