The Study On The Shifting Schedule Base On Economic-Dynamic Factor For Bus

The bus which is equipped with automatic transmission not only can satisfy thedemand for powerful and economic performance, but also can make the process of thevehicle starting, acceleration and gear shifting more smooth and more steady whichmeet the passengers’ requirement to comfort. Automatic transmission can make thedriver more relax, and ensure the security.Shifting schedule which is the key technology for automatic transmissiondirectly effect the vehicle driving performance.When City bus running on urban road, not only staring, acceleration, Shifting,parking and so on need frequently operation, but also passengers flow and loadvariation change frequently. Aimed at this characteristic of city bus, this paper hasadvanced the coefficient of fuel economy and power performance to analysis the shiftstrategy on the basis of the economy and the power shift schedule. The coefficientwhich can adjust the shift schedule due to the load of engine makes bus running withthe best power and economic performance.This paper has done works as follows:1.Basing on the reading of a number of literatures from both domestic andabroad, the development and the advantages of automatic transmission is introducedin the beginning of this paper.2.Introducing the works to prepare for the project, such as studing on the partswhich is consist of the electrical control system, sensor calibration, testing system,writing program and so on.3. The engine and torque converter’s input and output characteristics of jointwork have been studied on, and has built the power train and the vehicle mathematic model.4、Study on automatic shift theory, this paper has formulated the power shiftschedule and economic shift schedule. And on the basis of above, this paper hasadvanced the coefficient of fuel economy and power performance to analysis the shiftstrategy to adapt to different driving condition.5.This paper has analysis the result of vehicle experiment, and has validated thepracticability that whether the parameter of percentual load at current speed canrepresent the engine load. This paper has built the Simulink model, and ran theprocess. The result of the new shift schedule has more advantages than the power andeconomic shift schedule.6.finally, on the basis of above all, this paper has formulated the law of converterlocking, and built the Simulink model. The result suggest that transmission efficiencyhas been improve greatly through the control of converter locking.