Abstract: When continuously variable transmission(CVT) works under economic mode, backup power of engine is low. Engine can increase its output power mainly by increasing its rotation speed, which will consume corresponding power and make the vehicle lack of drive power during kick down conditions. Shift strategies based on real time parameters can move the working point of engine towards its peak power line only after a transient had began, as moving of engine working point can be achieved only by increasing the engine speed, these shift strategies can’t improve the vehicle power performance effectively. Statistic features of driving parameters have many choiceness characteristics as they contain the information of driving history, and can change along with the work conditions of vehicle. With this in mind, a control strategy based on statistic features of driving parameters is proposed to tune the target engine working point. Simulation and experiment results indicated that, the working point of engine can be tuned by the proposed control strategy properly when the work condition of vehicle changes. Moreover, the proposed control strategy avoids to depend on the real time parameters, and can make the engine works on a point with more backup power before a transient had began. Power performance of CVT equipped vehicle was improved effectively under the proposed control strategy.

Key words: Continuously variable transmission, Driving environment, Intelligent control strategy, Vehicles