eprintid: 433 rev_number: 15 eprint_status: archive userid: 7 dir: disk0/00/00/04/33 datestamp: 2011-07-27 08:34:14 lastmod: 2014-07-02 14:30:10 status_changed: 2011-07-27 08:34:14 type: book_section metadata_visibility: show item_issues_count: 0 creators_name: Trimboli, Sergio creators_name: Di Cairano, Stefano creators_name: Bemporad, Alberto creators_name: Kolmanovsky, Ilya creators_id: creators_id: creators_id: alberto.bemporad@imtlucca.it creators_id: title: Model predictive control for systems with time delay: an application to air-fuel ratio control in automotive engines ispublished: pub subjects: TA subjects: TJ divisions: CSA full_text_status: none keywords: engine control; model predictive control; time-delay systems; time-varying delays note: 8th IFAC Workshop on Time-Delay Systems (2009) abstract: To meet increasingly stringent emission regulations modern internal combustion engines require highly accurate control of the air-to-fuel ratio. The performance of the conventional air-to-fuel ratio feedback loop is limited by the combustion delay between fuel injection and engine exhaust, and by the transport delay for the exhaust gas to propagate to the air-to-fuel ratio sensor location. The combined delay is variable, since it depends on engine speed and airflow. Drivability, fuel economy and emission requirements result in constraints on the deviations of the air-to-fuel ratio, stored oxygen in the three-way catalyst, and fuel injection. This paper proposes an approach for air-to-fuel ratio control based on Model Predictive Control (MPC). The approach systematically handles both variable time delays and pointwise-in-time constraints. A delay-free model is considered first, which takes into account the dynamic relations between the injected fuel and the air-to-fuel ratio and the dynamics of the oxygen stored in the catalyst. For the delay-free model, the explicit MPC law is computed. Delay compensation is obtained by estimating the delay online from engine operating conditions, and feeding the MPC law with the state predicted ahead over the time interval of the estimated delay. The predicted state is computed by combining measurement filtering with forward iterations of the nonlinear dynamic equations of the model. The achieved performance in tracking the air-to-fuel ratio and the oxygen storage setpoints while enforcing the constraints is demonstrated in simulation using real data profiles. date: 2009 date_type: published volume: 8 publisher: IFAC pagerange: 90-95 event_title: 8th IFAC Workshop on Time Delay Systems event_location: 30 September 2009 event_dates: Sinaia, Romania id_number: 10.3182/20090901-3-RO-4009.00012 refereed: TRUE isbn: 10.3182/20090901-3-RO-4009.00012 book_title: Time Delay Systems official_url: http://www.ifac-papersonline.net/Detailed/43525.html citation: Trimboli, Sergio and Di Cairano, Stefano and Bemporad, Alberto and Kolmanovsky, Ilya Model predictive control for systems with time delay: an application to air-fuel ratio control in automotive engines. In: Time Delay Systems. IFAC, pp. 90-95. ISBN 10.3182/20090901-3-RO-4009.00012 (2009)