The synchronizer control strategy for dual clutch automatic transmission based on city drive cycle

Abstract

Based on vehicle parameters,engine torque and fuel consumption models of the car equipped with dual clutch automatic transmission (DCT),the optimal fuel economy shifting schedule of DCT is designed.According to the characteristic that synchronizers of DCT can be engaged in advance during the shift process,the control schedule of DCT synchronizers is put forward on the basis of the devised shifting schedule,which ensures the synchronizers can be accurately operated.Moreover,the variation characteristic of the speed and accelerator pedal when DCT vehicle drives in city drive cycle is analyzed,then,the specific control method of DCT synchronizers is put forward and the control diagram is described.The control results of DCT synchronizer in ECE+EUDC drive cycle are tested by using hardware in the loop simulation methods(HIL),and the test results indicate every synchronizer can be precisely implemented in city drive cycle and even in some extreme condition such as quickly step ping on or releasing the accelerator pedal,furthermore,the unnecessary engaging and disengaging process can be eliminated,the merits of the control strategy are validated.