Strategies for Reducing NO<sub>X</sub>- and Particulate Matter Emissions in Diesel Hybrid Electric Vehicles

Abstract

<div class="htmlview paragraph">In hybrid electric vehicles the combination of diesel engine and electric motor obviously provides lowest fuel consumption. However, compared with the Otto hybrid system, there are relatively high NO<sub>x</sub> and particulate matter emissions. This paper describes investigations of various strategies for a significant reduction of exhaust gas emissions in diesel hybrid electric vehicles.</div> <div class="htmlview paragraph">By reducing the dynamic operation of the combustion engine by supplementing the engine torque demand with an electric motor and limiting the maximum engine torque, the NO<sub>x</sub> emissions could be reduced by more than 30% and the particulate matter emissions by more than 20%, without influencing the fuel consumption compared to hybrid electric vehicles with conventional operation strategy.</div>