Title: Study on shift dynamics and shift quality of dual clutch transmissions
Authors: Jinle Zhang, Biao Ma, Manfred Zehn
Addresses: Vehicle Lab, School of Mechanical Engineering, Beijing Institute of Technology, 100081, China; FG Strukturmechanik und Strukturberechnung, Institut fur Mechanik, Technische Universitat Berlin, Sekr. C8-3, Str. d. 17. Juni 135, Berlin, 10623, Germany. ' Vehicle Lab, School of Mechanical Engineering, Beijing Institute of Technology, 100081, China. ' FG Strukturmechanik und Strukturberechnung, Institut fur Mechanik, Technische Universitat Berlin, Sekr. C8-3, Str. d. 17. Juni 135, Berlin, 10623, Germany
Abstract: Dual clutch transmissions (DCTs) offer full shift comfort, and significantly improved fuel efficiency and performance. This paper presents a model for the simulation and analysis of shift dynamics for DCT vehicles. A DCT structure for heavy duty trucks was proposed and the simulation model was built with the software Matlab/Simulink. System dynamic equations were derived according to the detailed analysis of upshifts and downshifts. The importance of engine throttle control, clutch apply timing and clutch pressure characteristics were quantitatively analysed and explained. Simulation results show that better shift quality can be achieved with proper throttle control. The release signal of off-going clutch should be initiated at the same time as the engaging signal of on-coming clutch in upshifts. Optimised clutch pressure can be achieved for smooth shifts by modifying the clutch pressure characteristics interactively based on the simulation results.
Keywords: shift dynamics; shift quality; dual clutch transmission; DCT; vehicle systems modelling; Matlab/Simulink; simulation; heavy duty trucks; heavy vehicles; upshifting; downshifting; engine throttle control; clutch apply timing; clutch pressure.
DOI: 10.1504/IJVSMT.2010.037122
International Journal of Vehicle Systems Modelling and Testing, 2010 Vol.5 No.2/3, pp.103 - 123
Received: 02 Nov 2009
Accepted: 05 Jan 2010
Published online: 25 Nov 2010 *