ISBN 9783843933551

978-3-8439-3355-1, Reihe Fahrzeugtechnik

Daliang Shen
Fuel-Optimal Powertrain Control of Range-Extender Hybrid Vehicles

182 Seiten, Dissertation Technische Universität Berlin (2017), Softcover, A5

Zusammenfassung / Abstract

Electric mobility attracts increasing attention from the automotive industry due to increasingly strict regulations of exhaust emissions. However, the low energy density of onboard batteries presents a great limitation on the range of pure electric vehicles; range-extender hybrid vehicles are considered as an attractive compromise, eliminating range anxiety with the range extender unit (RXU). To make the best use of the fuel-saving potential provided by the hybrid electric powertrain, this work aims to design a real-time capable and optimal powertrain control.

The developed control algorithm utilizes map data from navigation systems for predicting the future driving speed. Based on this preview knowledge, the algorithm calculates the fuel-optimal control regarding the power generation of RXU. This work illustrates the pathway to a novel numerical solver for the optimization, where mathematical modeling and analytical derivation applying Pontryagin's minimum principle are explained. The algorithm provides new insights into technically difficult issues concerning e.g. state constraints and non-convexity in the optimal control problem.

For the online implementation of the control design, a two-scale control architecture with a model predictive control paradigm is proposed. Simulation results demonstrate the fuel-saving proficiency and the real-time capability of the proposed powertrain control, as well as its robustness against prediction inaccuracies.