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To downsize a spark ignited (SI) internal combustion engine (ICE), keeping suitable power levels, the application of turbocharging is mandatory. The possibility to couple an electric drive to the turbocharger (electric turbo compound, ETC) can be considered, as demonstrated by a number of studies and the current application in the F1 Championship, since it allows to extend the boost region to the lowest ICE rotational speeds and to reduce the turbo lag. As well, some recovery of the exhaust gas residual energy to produce electrical energy is possible. The present paper shows the first numerical results of a research program under way in collaboration between the Universities of Pisa and Genoa. The study is focused on the evaluation of the benefits resulting from the application of ETC to a twin-cylinder small SI engine (900 cm3).

Lithium batteries are increasingly being considered for installation as power sources in electric and hybrid vehicles, because of their high specific energy and power. To effectively size the vehicle Rechargeable Energy Storage System, it is very important to be able to mathematically model their behaviour. Battery modelling is also very useful for on-line management of electric and hybrid vehicles. This paper presents a dynamic model of lithium batteries based on experimental tests on high power Lithium-polymer models. The results can be adapted, with suitable parameter evaluation, to other lithium batteries as well.

This paper presents the some issues related to modeling of hydrogen fuel-cell based propulsion systems and the main characteristics of the corresponding simulation program developed in Matlab-Simulink™ environment by the authors. Although several hybrid vehicle simulators are available today, often researchers prefer to create programs of their own, to pursue specific pursues. The authors have gone in this direction, and with this paper they intend to share this experience with readers wanting to do a similar job, hoping they can find useful hints to direct their activity. The paper shows therefore the main issues to be tackled when creating hybrid vehicle simulation programs in general, and fuel-cell based in particular, and gives some details on individual component modeling.

This paper reports and analyses experimental results showing the performances of two state-of-the art, commercially available storage systems, adequate for use onboard hybrid vehicles, i.e. a supercapacitor (SC) and a super-high power lithium battery. The two devices were subjected to specific experimental tests adequate to ease comparisons for use onboard hybrid vehicles. The results are expressed mainly in terms of specific power and charge/discharge efficiency as a function of the wanted discharge time; they show that, if future cycle efficiency analyses do not reverse the result, very high power lithium batteries are a very competitive candidate for use as onboard storage within hybrid vehicles, when storage of a single technology are considered.