Abstract
In order to reduce the emissions of the heavy-duty diesel hybrid vehicles (HEV), it is necessary to provide the high exhaust-gas temperature and to keep aftertreatment system effective. But the engine load of the HEV is assisted by the electric motor. Therefore, the aftertreatment system of these vehicles is not able to get the enough high exhaust-gas temperature. For example, the emission characteristics of the HEV are worsen at the urban driving mode. In this study, the electric heating catalyst system (EHC) for the HEV was equipped. The fuel economy and emission characteristics of this vehicle were estimated. This result is that the EHC showed good performance at the engine low speed and low torque range. And, NOx emission was reduced when the tailpipe layout was setup in order of the urea solution injector, EHC and SCR catalyst. The fuel economy of the HEV with the EHC was slightly decreased, but the emissions were much improved.
