Advanced Emission Control System for ULEV2 Application

Global environmental consideration is now one of the essential components in automotive design. This concern needs be addressed not only by aftertreatment systems but also engine control technologies. In this paper, we will present an efficient emission control system that has been designed based upon the combination of advanced engine control and catalyst technologies. The system has successfully achieved the stringent US ULEV2 emission regulations and the vehicle installed with this system has been commercialized in the marketplace.

In this system, the advanced fuel control system was able to facilitate quick light-off of the catalyst so that the cold start emission could be minimized. The engine A/F control is so precise that the catalyst can use the material which is most effective at the stoichiometric point.

On the catalyst development side, the formulation has been optimized for the reduction of cold start emission by fully utilizing the quick temperature ramp-up offered by the engine control. The catalyst material was also optimized for improved response, so that the engine control system could maximize its benefits under warmed-up condition. In addition, sulfur resistance and phosphorous poisoning issues were also addressed. As the final catalyst system, the PGM usage was reduced to a much lower level than that of the previous generation.