Documents disponibles écrits par cet auteur

EGR-VGT control and tuning for pumping work minimization and emission control / Johan Wahlstrom in IEEE Transactions on control systems technology, Vol. 18 N° 4 (Juillet 2010) 

Public ISBD [article]  in IEEE Transactions on control systems technology > Vol. 18 N° 4 (Juillet 2010) . - pp. 993-1003 Titre : EGR-VGT control and tuning for pumping work minimization and emission control Type de document : texte imprimé Auteurs : Johan Wahlstrom, Auteur ; Lars Eriksson, Auteur ; Lars Nielsen, Auteur Année de publication : 2011 Article en page(s) : pp. 993-1003 Note générale : Génie Aérospatial Langues : Anglais (eng) Mots-clés : Diesel  engine  modeling  Exhaust  gas  recirculation  (EGR)  fraction  Engine  control  Oxygen/fuel  ration  Proportonal  integral  derivative  (PID) Index. décimale : 629.1 Résumé : A control structure is proposed and investigated for coordinated control of exhaust gas recirculation (EGR) valve and variable geometry turbochargers (VGT) position in heavy duty diesel engines. Main control goals are to fulfill the legislated emission levels, to reduce the fuel consumption, and to fulfill safe operation of the turbocharger. These goals are achieved through regulation of normalized oxygen/fuel ratio, λO, and intake manifold EGR-fraction. These are chosen both as main performance variables and feedback variables since they contain information about when it is possible to decrease the fuel consumption by minimizing the pumping work. Based on this a novel and simple pumping work minimization strategy is developed. The proposed performance variables are also strongly coupled to the emissions which makes it easier to adjust set-points, e.g., depending on measured emissions during an emission calibration process, since it is more straightforward than control of manifold pressure and air mass flow. Further, internally the controller is structured to handle the different control objectives. Controller tuning is important for performance but can be time consuming so the controller objectives are captured in a cost function, which makes automatic tuning possible even though objectives are conflicting. Performance tradeoffs are necessary and are illustrated on the European Transient Cycle. The controller is validated in an engine test cell, where it is experimentally demonstrated that the controller achieves all the control objectives and that the current production controller has at least 26% higher pumping losses compared to the proposed controller. DEWEY : 629.1 ISSN : 1063-6536 En ligne : http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5282503 [article] EGR-VGT control and tuning for pumping work minimization and emission control [texte imprimé] / Johan Wahlstrom, Auteur ; Lars Eriksson, Auteur ; Lars Nielsen, Auteur . - 2011 . - pp. 993-1003. Génie Aérospatial Langues : Anglais (eng) in IEEE Transactions on control systems technology > Vol. 18 N° 4 (Juillet 2010) . - pp. 993-1003 Mots-clés : Diesel  engine  modeling  Exhaust  gas  recirculation  (EGR)  fraction  Engine  control  Oxygen/fuel  ration  Proportonal  integral  derivative  (PID) Index. décimale : 629.1 Résumé : A control structure is proposed and investigated for coordinated control of exhaust gas recirculation (EGR) valve and variable geometry turbochargers (VGT) position in heavy duty diesel engines. Main control goals are to fulfill the legislated emission levels, to reduce the fuel consumption, and to fulfill safe operation of the turbocharger. These goals are achieved through regulation of normalized oxygen/fuel ratio, λO, and intake manifold EGR-fraction. These are chosen both as main performance variables and feedback variables since they contain information about when it is possible to decrease the fuel consumption by minimizing the pumping work. Based on this a novel and simple pumping work minimization strategy is developed. The proposed performance variables are also strongly coupled to the emissions which makes it easier to adjust set-points, e.g., depending on measured emissions during an emission calibration process, since it is more straightforward than control of manifold pressure and air mass flow. Further, internally the controller is structured to handle the different control objectives. Controller tuning is important for performance but can be time consuming so the controller objectives are captured in a cost function, which makes automatic tuning possible even though objectives are conflicting. Performance tradeoffs are necessary and are illustrated on the European Transient Cycle. The controller is validated in an engine test cell, where it is experimentally demonstrated that the controller achieves all the control objectives and that the current production controller has at least 26% higher pumping losses compared to the proposed controller. DEWEY : 629.1 ISSN : 1063-6536 En ligne : http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5282503

A parametric model for ionization current in a four stroke SI engine / Ingemar Andersson in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 131 N°2 (Mars/Avril 2009) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°2 (Mars/Avril 2009) . - 11 p. Titre : A parametric model for ionization current in a four stroke SI engine Type de document : texte imprimé Auteurs : Ingemar Andersson, Auteur ; Lars Eriksson, Auteur Année de publication : 2009 Article en page(s) : 11 p. Note générale : dynamic systems Langues : Anglais (eng) Mots-clés : pressure;  temperature;  ionization;  combustion;  fuels;  cylinders Résumé : A model for the thermal part of an ionization signal is presented that connects the ionization current to cylinder pressure and temperature in a spark ignited internal combustion engine. One strength of the model is that, after calibration, it has only two free parameters: burn angle and initial kernel temperature. By fitting the model to a measured ionization signal, it is possible to estimate both cylinder pressure and temperature, where the pressure is estimated with good accuracy. The model approach is validated on engine data. Cylinder pressure and ionization current data were collected on a Saab four-cylinder spark ignited engine for a variation in ignition timing and air-fuel ratio. The main result is that the parametrized ionization current model can be used to estimating combustion properties as pressure, temperature, and content of nitric oxides based on measured ionization currents. The current status of the model is suitable for off-line analysis of ionization currents and cylinder pressure. This ionization current model not only describes the connection between the ionization current and the combustion process, but also offers new possibilities for engine management system to control the internal combustion engine. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...] [article] A parametric model for ionization current in a four stroke SI engine [texte imprimé] / Ingemar Andersson, Auteur ; Lars Eriksson, Auteur . - 2009 . - 11 p. dynamic systems Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 131 N°2 (Mars/Avril 2009) . - 11 p. Mots-clés : pressure;  temperature;  ionization;  combustion;  fuels;  cylinders Résumé : A model for the thermal part of an ionization signal is presented that connects the ionization current to cylinder pressure and temperature in a spark ignited internal combustion engine. One strength of the model is that, after calibration, it has only two free parameters: burn angle and initial kernel temperature. By fitting the model to a measured ionization signal, it is possible to estimate both cylinder pressure and temperature, where the pressure is estimated with good accuracy. The model approach is validated on engine data. Cylinder pressure and ionization current data were collected on a Saab four-cylinder spark ignited engine for a variation in ignition timing and air-fuel ratio. The main result is that the parametrized ionization current model can be used to estimating combustion properties as pressure, temperature, and content of nitric oxides based on measured ionization currents. The current status of the model is suitable for off-line analysis of ionization currents and cylinder pressure. This ionization current model not only describes the connection between the ionization current and the combustion process, but also offers new possibilities for engine management system to control the internal combustion engine. DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://dynamicsystems.asmedigitalcollection.asme.org/issue.aspx?journalid=117&is [...]