Diesel Engine Transient NOx and Airpath Control using Rate-based Model Predictive Controller

This paper presents a rate-based model predictive control (MPC) design to track a fuel optimal reference intake manifold pressure (Pim) without violating tailpipe oxides of Nitrogen (NOx) constraints utilizing dynamic linear air path and NOx model for one-step ahead prediction of a heavy-duty diesel engine. Hardware-in-the-loop experimental validation shows efficient tracking of desired intake manifold pressure with 1.4 % reduction in brake-specific fuel consumption, 2 % reduction in brake-specific engine-out NOx, 40 % reduction in brake-specific tailpipe NOx, and 6 % reduction in brake-specific urea consumption. This short horizon controller with minimal computational load can be either used as a standalone Pim controller with emission constraint or in a hierarchical controller architecture.