Observer Based Feedforward Air-Fuel Control of Turbocharged SI-Engines
| Authors: | Andersson Per, Linkopings Universitet, Sweden
Eriksson Lars, Linkopings Universitet, Sweden |
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| Topic: | 7.1 Automotive Control |
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| Session: | Engine Control |
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| Keywords: | automotive control, automotive emissions, engine management, engine modeling, estimators, extended kalman filters, model based control |
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Abstract
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 condition to a predictor which is used for feedforward of the CAC for air-fuel control. The resulting controller is experimentally validated on a SAAB 2.0 dm^3 TC engine using tip-in and tip-out transients. The results show that the excursions in lambda are less than 5%.
