Model predictive control of partially premixed combustion

Partially premixed combustion is a compression ignited combustion strategy where high exhaust gas recirculation (EGR) levels in combination with early or late injection timing result in a prolonged ignition delay yielding a more premixed charge than with conventional diesel combustion. With this concept it is possible to get low smoke and NOx emissions simultaneously. Accurate control of injection timing and injection duration is however necessary in order to achieve this favorable mode of combustion. This chapter presents a method for controlled PPC operation. The approach is to control the time between end of injection and start of combustion which if positive yields sufficient premixing. Model Predictive Control was used to control the engine which was modeled using System Identification. The results show that it is possible to assure PPC operation in the presence of both speed/load transients and EGR disturbances. © 2010 Springer-Verlag London.