Coordinated emissions control system of a diesel engine with selective catalytic reduction

A system for reducing environmentally harmful emissions from an internal combustion engine. The system incorporates an exhaust after-treatment device, which uses selective catalytic reduction to remove NOx from the exhaust of the engine. The engine is managed by a controller (K eng ,21) and the exhaust after-treatment device may be managed by another controller (K scr ,31). These controllers are managed by a third controller (K,39) that provides a coordinated control of engine performance and emissions reduction. The engine and the exhaust after-treatment device may be modeled to aid in designing and building a system for the coordinated control. The controllers may be predictive model controllers.