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Determining model accuracy requirements for automotive engine coldstart hydrocarbon emissions control / Nasser L. Azad in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 134 N° 5 (Septembre 2012) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 134 N° 5 (Septembre 2012) . - 11 p. Titre : Determining model accuracy requirements for automotive engine coldstart hydrocarbon emissions control Type de document : texte imprimé Auteurs : Nasser L. Azad, Auteur ; Pannag R. Sanketi, Auteur ; Hedrick, J. Karl, Auteur Année de publication : 2012 Article en page(s) : 11 p. Note générale : Dynamic systems Langues : Anglais (eng) Mots-clés : Automotive  engine  Systematic  method  Coldstart  hydrocarbon  (HC)  emissions  Accuracy  requirements Index. décimale : 629.8 Résumé : In this work, a systematic method is introduced to determine the required accuracy of an automotive engine model used for real-time optimal control of coldstart hydrocarbon (HC) emissions. The engine model structure and development are briefly explained and the model predictions versus experimental results are presented. The control design problem is represented with a dynamic optimization formulation on the basis of the engine model and solved using the Pontryagin's minimum principle (PMP). To relate the level of plant/model mismatch and the control performance degradation in practice, a sensitivity analysis using a computationally efficient method is employed. In this way, the sensitivities or the effects of small parameter variations on the optimal solution, which is the minimum of cumulative tailpipe HC emissions over the coldstart period, are calculated. There is a good agreement between the sensitivity analysis results and the experimental data. The sensitivities indicate the directions of the subsequent parameter estimation and model improvement tasks to enhance the control-relevant accuracy, and thus, the control performance. Furthermore, they provide some insights to simplify the engine model, which is critical for real-time implementation of the coldstart optimal control system. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000134000005 [...] [article] Determining model accuracy requirements for automotive engine coldstart hydrocarbon emissions control [texte imprimé] / Nasser L. Azad, Auteur ; Pannag R. Sanketi, Auteur ; Hedrick, J. Karl, Auteur . - 2012 . - 11 p. Dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 134 N° 5 (Septembre 2012) . - 11 p. Mots-clés : Automotive  engine  Systematic  method  Coldstart  hydrocarbon  (HC)  emissions  Accuracy  requirements Index. décimale : 629.8 Résumé : In this work, a systematic method is introduced to determine the required accuracy of an automotive engine model used for real-time optimal control of coldstart hydrocarbon (HC) emissions. The engine model structure and development are briefly explained and the model predictions versus experimental results are presented. The control design problem is represented with a dynamic optimization formulation on the basis of the engine model and solved using the Pontryagin's minimum principle (PMP). To relate the level of plant/model mismatch and the control performance degradation in practice, a sensitivity analysis using a computationally efficient method is employed. In this way, the sensitivities or the effects of small parameter variations on the optimal solution, which is the minimum of cumulative tailpipe HC emissions over the coldstart period, are calculated. There is a good agreement between the sensitivity analysis results and the experimental data. The sensitivities indicate the directions of the subsequent parameter estimation and model improvement tasks to enhance the control-relevant accuracy, and thus, the control performance. Furthermore, they provide some insights to simplify the engine model, which is critical for real-time implementation of the coldstart optimal control system. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://asmedl.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA000134000005 [...]