An engine control systems design for low-emission vehicles by generalized predictive control based on identified model

Conservation of the environment has become critical to the automotive industry. Recently, requirements for onboard diagnostic and engine control systems have been strictly enforced. In the present paper, in order to meet the requirements for low-emission vehicles, a novel method for construction of the air-fuel ratio (A/F) control system is proposed. The method of construction of the system is divided into two steps. The first step is to design the A/F control system for the engine based on an open loop design. The second step is to design the A/F control system for the catalyst system. The design method is based on generalized predictive control in order to assure robustness to open loop control as well as model uncertainty. The effectiveness of the proposed A/F control system is verified through experiments using full-scale products.