Authors: Martin Kaszynski, Oliver Sawodny
Addresses: Institute for System Dynamics, University of Stuttgart, 70569 Stuttgart, Germany. ' Institute for System Dynamics, University of Stuttgart, 70569 Stuttgart, Germany
Abstract: In this paper, the fuel savings potential of parallel hybrid hydraulic vehicles with (automated) manual transmission is assessed. An adapted model of a hybrid hydraulic truck is used to compute the optimal control strategy for a given velocity profile as a reference. Special care is given to include practical conditions in the optimisation framework so that realistic trajectories are calculated, and to integrate the effects of clutch operation into the set-up. Previous works of other authors are employed to define a baseline power management strategy. Several elements of the optimal control (gear shifts, clutch operation, torque distribution) are analysed and compared with the baseline strategy to assess the major differences and the possible realisation of the remaining fuel savings potential. On the basis of the corresponding findings, a new approach to design a realistic, predictive supervisory control is developed and the potential of the new concept is demonstrated.
Keywords: hybrid vehicles; hydraulic hybrid propulsion; optimisation; dynamic programming; power management; supervisory control; fuel savings potential; hybrid trucks; mathematical modelling; optimal control; velocity profile; gear shifts; clutch operation; torque distribution; hydraulic propulsion; hybrid powertrains; heavy vehicles.
International Journal of Powertrains, 2011 Vol.1 No.1, pp.22 - 42
Published online: 26 Feb 2015 *Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article