Towards Robust H-infinity Control of an SI Engine's Air/Fuel Ratio 1999-01-0854
Long term stoichiometric Air/Fuel Ratio (AFR) control of an SI engine is at the present mainly maintained by table mapping of the engine's fresh air intake as a function of the engine operating point. In order to reduce a stationary error in the AFR to zero the table based control normally works in conjunction with a PI feedback from a HEGO sensor. The effective bandwidth of this feedback loop is quite small and seldom exceeds 2 Hz. This is altogether too small for accurate transient AFR control.
This paper presents a new λ (normalized Air/Fuel Ratio) control methodology (H∞ control) which has a somewhat larger bandwidth and can guarantee robustness with respect to selected engine variable and parameter variations.
Christian Winge Vigild, Karsten P.H. Andersen, Elbert Hendricks, Michael Struwe
Technical University of Denmark, Sander-Hansen
International Congress & Exposition
Electronic Engine Control Technologies-PT-73, Electronic Engine Controls 1999: Neural Networks, Diagnostic and Electronic Hardware, and Controls-SP-1419, SAE 1999 Transactions - Journal of Engines-V108-3