Predictive design of linear feedback/feedforward controller for automotive VCT engine

The challenges of automotive powertrain control are threefold: to meet the requirements of customers in terms of performance and fuel economy to meet the requirements of society as reflected by governmental regulations, and to achieve these requirements rapidly and efficiently in order to bring innovative products to a competitive market in a timely manner. This paper addresses the design of a fuel control subsystem for an engine with variable cam timing. The controller is designed as an independent software module. The control objective is to maintain the air-fuel ratio at the stoichiometric value despite disturbance inputs from the cam, throttle, or engine speed. The technical approach is based on predictive control methodology. Specifically, a receding horizon controller suitable for an embedded application is developed. The controller design is performed off-line. The resulting feedforward controller compensates the transient processes caused by the disturbance inputs. The controller is further simplified by parametric approximation