Control of variable geometry turbocharged diesel engines for reduced emissions

A multivariable control scheme is designed to minimize emission of nitrogen oxides (NO/sub x/) and generation of smoke in a diesel engine equipped with a variable geometry turbocharger (VGT) and an external exhaust gas recirculation system (EGR). Steady-state optimization results in operating points where NO/sub x/ emissions and smoke generation are highly coupled and require joint management by VGT and EGR actuators.