Precise air/fuel control is necessary for low emissions in turbocharged (TC) SI-engines. Observers are often proposed for accurate cylinder air charge estimation in air/fuel controllers. First it is shown using a structural method that the system is locally structurally observable using observer-feedback from any measured state. A systematic method to select observer feedback signals is importa...

Air-fuel control on turbocharged (TC) SI-engines require precise prediction of the cylinder air-charge (CAC). Using an observer it is possible to both estimate the necessary system states and to provide a framework to design the necessary CAC feedforward controller. Here a mean value engine model of a TC SI-engine is used to develop an observer. The output of the observer is fed as an initial c...

This paper presents a feedback deign approach to the cold-start speed control for spark ignition engines. First, in order to ensure successful combustion in the transient mode, a fuel injection controller is given based on the air charge estimation with inverse dynamics of fuel path, which is a dual sampling rate system, i.e. the estimation for the air charge is performed TDC-based, and the fue...

Knock is an undesirable event that causes most of the abnormal combustion in spark ignition (SI) engines. In this paper, a novel knock intensity diagnosis method for SI engines by vibration analysis based on the ensemble empirical mode decomposition (EEMD) is proposed. First, the vibration signal measured from the test SI engine cylinder head is decomposed by the EEMD. Because the EEMD can elim...