Abstract
In this paper to change the engine throttle opening automatically during the gear shifting to carry out dynamic synthetic control towards the power train system for realizing the optimum match of assembles. But the control law has the by-product as the inconsistency of the throttle opening decided by accelerator pedal and the actual throttle opening after entering the new gear position. The research focuses on solving the contradiction by applying the DBW characteristics. The DBW is an important connection of vehicle human - machine system. It solves a serious of problems brought by the inconsistency of accelerator pedal and throttle opening, and insures gears shifted precisely according to the optimum changing throttle schedule.