eprintid: 1200 rev_number: 7 eprint_status: archive userid: 6 dir: disk0/00/00/12/00 datestamp: 2012-02-29 16:10:39 lastmod: 2012-02-29 16:10:39 status_changed: 2012-02-29 16:10:39 type: book_section metadata_visibility: show 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 with delay compensation for air-to-fuel ratio control ispublished: pub subjects: QA75 subjects: TJ divisions: CSA full_text_status: none 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: 2012 date_type: published series: Lecture Notes in Information Sciences number: 423 publisher: Springer place_of_pub: Berlin pagerange: 319-330 id_number: 10.1007/978-3-642-25221-1_24 refereed: TRUE isbn: 978-3-642-25220-4 issn: 0170-8643 book_title: Time delay systems: methods, applications and new trends editors_name: Sipahi, Rifat editors_name: Vyhlídal, Tomáš editors_name: Niculescu, Silviu-Iulian editors_name: Pepe, Pierdomenico official_url: http://dx.doi.org/10.1007/978-3-642-25221-1_24 citation: Trimboli, Sergio and Di Cairano, Stefano and Bemporad, Alberto and Kolmanovsky, Ilya Model predictive control with delay compensation for air-to-fuel ratio control. In: Time delay systems: methods, applications and new trends. Lecture Notes in Information Sciences (423). Springer, Berlin, pp. 319-330. ISBN 978-3-642-25220-4 (2012)