Search Results

State of the art battery electric vehicles (BEVs) become increasingly attractive, thanks to their top performance and high energy efficiency. Nevertheless, despite improvements in electric motors efficiency and motive batteries technology, there is still space for improving BEVs’ autonomy. Among others, use of a multi-speed, instead of a single-speed transmission system has the potential to optimize BEV’s energy consumption and driving range. In this respect, the scope of this work is to demonstrate a novel model-based approach for evaluating the potential of multi-speed gear box technology. For this purpose, advanced vehicle modeling was combined with statistical analysis tools and an optimization algorithm, with an aim to optimize gear ratios and the respective gear shifting strategy, ultimately maximizing BEV’s autonomy and performance.

City buses electrification gains increasing interest as a promising solution for both zero emissions in urban environment and energy consumption minimization. Nevertheless, global spread of battery electric buses may be currently questionable, mainly due to traveling range limitations. In this respect, the aim of this work is to elucidate performance aspects of battery electric powertrain systems for urban buses. Instead of exhaustive testing, cost-effective model based vehicle analysis is proposed for quantifying and understanding electric propulsion system performance and respective vehicle energy consumption. First, an indicative 12-m battery electric urban bus model was developed and its performance was simulated under both steady state conditions, as well as the legislated Braunschweig driving cycle.