Adaptive gearshift control of wet dual clutch transmission based on extended state observer and H∞ robust control

The clutch characteristics of dual clutch transmission (DCT) will change as the service time increases, which will lead to the deterioration of gearshift performance. To reduce the influence of the change in clutch characteristics on the gearshift performance, an adaptive gearshift control method based on the extended state observer and H∞ robust control is proposed. First, the gearshift problem of the DCT is transformed into the reference trajectory tracking problem, and the gearshift reference trajectory is designed using the minimum principle. The uncertain term related to the change in clutch characteristics in the DCT gearshift dynamic model is defined, and an extended state observer is designed to estimate the uncertain term. On this basis, the gearshift controller is designed using the backstepping method, and H∞ robust control is introduced to further improve the adaptation effect of the controller, then the adaptive control laws of the clutch pressure and engine torque are obtained. Finally, the adaptation effect of the proposed method was verified by both simulation and experiment. The results show that the proposed adaptive gearshift control method can effectively avoid the gearshift delay caused by the change in clutch characteristics, and the gearshift jerk in the simulation and experiment is reduced by 55.01% and 34.8%, respectively.

Gearshift control strategies for hybrid electric vehicles: A comparison of powertrains equipped with automated manual transmissions and dual-clutch transmissions

This article describes gearshift control strategies developed for a series-parallel hybrid electric vehicle architecture in which an electric machine is connected to the output of the transmission, thus obtaining torque filling capabilities during gearshifts. Two transmission systems are analyzed: hybrid automated manual transmission and hybrid dual-clutch transmission. The article focuses on the gearshift control strategies for the two transmission, splitting each gearshift into several phases. The objectives of each control phase, the equations for computing the set points for powertrain actuators, and the conditions that determine the passage from one shifting phase to the next are reported. Moreover, nonlinear dynamic models are described and used to verify through simulation the effectiveness of the controllers. Promising results, in terms of vehicle dynamic performance, are obtained for both transmission systems.