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Air-fuel-ratio control of engine system with unknown input observer

Research output: Chapter in Book/Report/Conference proceedingConference contribution

Original languageEnglish
Title of host publication2016 UKACC 11th International Conference on Control (CONTROL)
Publisher or commissioning bodyInstitute of Electrical and Electronics Engineers (IEEE)
Number of pages6
ISBN (Electronic)978-1-4673-9891-6
ISBN (Print)978-1-4673-9892-3
DateAccepted/In press - 16 May 2016
DatePublished (current) - 10 Nov 2016
Event2016 UKACC 11th International Conference on Control (CONTROL) - Queen's University, Belfast, Ireland
Duration: 31 Aug 20162 Sep 2016


Conference2016 UKACC 11th International Conference on Control (CONTROL)


This paper presents an alternative control to maintain the air-fuel-ratio (AFR) of port-injected spark ignition (SI) engines at certain value, i.e. stoichiometric value, to improve the fuel economy. We first reformulate the AFR regulation problem as a tracking control for the injected fuel mass flow rate, which can simplify the control synthesis when the fuel film dynamics are taken into account. The unknown engine parameters and dynamics can be lumped as an unknown signal, and then compensated by incorporating the unknown input observer into the control design. Only the measurable air mass flow rate through throttle, manifold pressure and temperature, and the universal exhaust gas oxygen (UEGO) sensor are utilized. Simulations based on a mean-value engine model (MVEM) illustrate that the proposed control can achieve satisfactory transient and steady-state performance with strong robustness when the engine is operated in varying speed conditions.

    Research areas

  • Air-to-fuel ratio control, Spark ignition engine, Unknown input observer, Mean-value engine model


2016 UKACC 11th International Conference on Control (CONTROL)

Duration31 Aug 20162 Sep 2016
Location of eventQueen's University
Degree of recognitionInternational event

Event: Conference

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  • Full-text PDF (accepted author manuscript)

    Rights statement: This is the accepted author manuscript (AAM). The final published version (version of record) is available online via IEEE at DOI: 10.1109/CONTROL.2016.7737647. Please refer to any applicable terms of use of the publisher.

    Accepted author manuscript, 656 KB, PDF-document


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