Documents disponibles écrits par cet auteur

A model based estimator for cylinder specific air-to-fuel ratio corrections / Meyer, Jason A. in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 133 N° 3 (Mai 2011) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 3 (Mai 2011) . - 14 p. Titre : A model based estimator for cylinder specific air-to-fuel ratio corrections Type de document : texte imprimé Auteurs : Meyer, Jason A., Auteur ; Yurkovich, Stephen, Auteur ; Midlam-Mohler, Shawn, Auteur Année de publication : 2011 Article en page(s) : 14 p. Note générale : Systèmes dynamiques Langues : Anglais (eng) Mots-clés : Closed  loop  systems  Engines  Exhaust  systems  Feedback  Feedforward  FIR  filters  Fuel  systems  Mechanical  variables  control  Open  loop  systems Index. décimale : 629.8 Résumé : One of the most overlooked and oversimplified components of an engine model used for model based air-to-fuel ratio (AFR) control and/or diagnostics is the exhaust gas dynamics model. Without a proper model of the exhaust system, the mixing of exhaust gases and the dynamic transport delays are challenging to capture accurately, even with a meticulous experimental calibration. By representing the exhaust system with a finite impulse response (FIR) model whose coefficients are based on physical properties, these effects can be predicted accurately and smoothly across the complete range of operating conditions. Through on-line and off-line techniques, this model can markedly improve the performance of both open loop and closed loop AFR control. Because a FIR model has a linear relationship between the input and the output, the input error trajectory can be identified from a single precatalyst oxygen sensor measurement. This technique can be used to supplement the calibration of either the feed-forward or feedback portion of the AFR controller. Additionally, the FIR model can be used for on-line estimation of cylinder imbalance errors. This model based approach to cylinder imbalance estimation has several advantages over the current empirically based methods including robustness and ease of calibration. DEWEY : 629.8 ISSN : 0022.0434 En ligne : http://asmedl.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...] [article] A model based estimator for cylinder specific air-to-fuel ratio corrections [texte imprimé] / Meyer, Jason A., Auteur ; Yurkovich, Stephen, Auteur ; Midlam-Mohler, Shawn, Auteur . - 2011 . - 14 p. Systèmes dynamiques Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 3 (Mai 2011) . - 14 p. Mots-clés : Closed  loop  systems  Engines  Exhaust  systems  Feedback  Feedforward  FIR  filters  Fuel  systems  Mechanical  variables  control  Open  loop  systems Index. décimale : 629.8 Résumé : One of the most overlooked and oversimplified components of an engine model used for model based air-to-fuel ratio (AFR) control and/or diagnostics is the exhaust gas dynamics model. Without a proper model of the exhaust system, the mixing of exhaust gases and the dynamic transport delays are challenging to capture accurately, even with a meticulous experimental calibration. By representing the exhaust system with a finite impulse response (FIR) model whose coefficients are based on physical properties, these effects can be predicted accurately and smoothly across the complete range of operating conditions. Through on-line and off-line techniques, this model can markedly improve the performance of both open loop and closed loop AFR control. Because a FIR model has a linear relationship between the input and the output, the input error trajectory can be identified from a single precatalyst oxygen sensor measurement. This technique can be used to supplement the calibration of either the feed-forward or feedback portion of the AFR controller. Additionally, the FIR model can be used for on-line estimation of cylinder imbalance errors. This model based approach to cylinder imbalance estimation has several advantages over the current empirically based methods including robustness and ease of calibration. DEWEY : 629.8 ISSN : 0022.0434 En ligne : http://asmedl.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...]

A model-based methodology for real-time estimation of diesel engine cylinder pressure / Ahmed Al Durra in Transactions of the ASME . Journal of dynamic systems, measurement, and control, Vol. 133 N° 3 (Mai 2011) 

Public ISBD [article]  in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 3 (Mai 2011) . - 09 p. Titre : A model-based methodology for real-time estimation of diesel engine cylinder pressure Type de document : texte imprimé Auteurs : Ahmed Al Durra, Auteur ; Canova, Marcello, Auteur ; Yurkovich, Stephen, Auteur Année de publication : 2011 Article en page(s) : 09 p. Note générale : Systèmes dynamiques Langues : Anglais (eng) Mots-clés : Closed  loop  systems  Combustion  Diesel  engines  Kalman  filters  Least  squares  approximations  Pressure  sensors  Recursive  estimation Index. décimale : 629.8 Résumé : Cylinder pressure is one of the most important parameters characterizing the combustion process in an internal combustion engine. The recent developments in engine control technologies suggest the use of cylinder pressure as a feedback signal for closed-loop combustion control. However, the sensors measuring in-cylinder pressure are typically subject to noise and offset issues, requiring signal processing methods to be applied to obtain a sufficiently accurate pressure trace. The signal conditioning implies a considerable computational burden, which ultimately limits the use of cylinder pressure sensing to laboratory testing, where the signal can be processed off-line. In order to enable closed-loop combustion control through cylinder pressure feedback, a real-time algorithm that extracts the pressure signal from the in-cylinder sensor is proposed in this study. The algorithm is based on a crank-angle based engine combustion of that predicts the in-cylinder pressure from the definition of a burn rate function. The model is then adapted to model-based estimation by applying an extended Kalman filter in conjunction with a recursive least-squares estimation scheme. The estimator is tested on a high-fidelity diesel engine simulator as well as on experimental data obtained at various operating conditions. The results obtained show the effectiveness of the estimator in reconstructing the cylinder pressure on a crank-angle basis and in rejecting measurement noise and modeling errors. Furthermore, a comparative study with a conventional signal processing method shows the advantage of using the derived estimator, especially in the presence of high signal noise (as frequently happens with low-cost sensors). DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://asmedl.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...] [article] A model-based methodology for real-time estimation of diesel engine cylinder pressure [texte imprimé] / Ahmed Al Durra, Auteur ; Canova, Marcello, Auteur ; Yurkovich, Stephen, Auteur . - 2011 . - 09 p. Systèmes dynamiques Langues : Anglais (eng) in Transactions of the ASME . Journal of dynamic systems, measurement, and control > Vol. 133 N° 3 (Mai 2011) . - 09 p. Mots-clés : Closed  loop  systems  Combustion  Diesel  engines  Kalman  filters  Least  squares  approximations  Pressure  sensors  Recursive  estimation Index. décimale : 629.8 Résumé : Cylinder pressure is one of the most important parameters characterizing the combustion process in an internal combustion engine. The recent developments in engine control technologies suggest the use of cylinder pressure as a feedback signal for closed-loop combustion control. However, the sensors measuring in-cylinder pressure are typically subject to noise and offset issues, requiring signal processing methods to be applied to obtain a sufficiently accurate pressure trace. The signal conditioning implies a considerable computational burden, which ultimately limits the use of cylinder pressure sensing to laboratory testing, where the signal can be processed off-line. In order to enable closed-loop combustion control through cylinder pressure feedback, a real-time algorithm that extracts the pressure signal from the in-cylinder sensor is proposed in this study. The algorithm is based on a crank-angle based engine combustion of that predicts the in-cylinder pressure from the definition of a burn rate function. The model is then adapted to model-based estimation by applying an extended Kalman filter in conjunction with a recursive least-squares estimation scheme. The estimator is tested on a high-fidelity diesel engine simulator as well as on experimental data obtained at various operating conditions. The results obtained show the effectiveness of the estimator in reconstructing the cylinder pressure on a crank-angle basis and in rejecting measurement noise and modeling errors. Furthermore, a comparative study with a conventional signal processing method shows the advantage of using the derived estimator, especially in the presence of high signal noise (as frequently happens with low-cost sensors). DEWEY : 629.8 ISSN : 0022-0434 En ligne : http://asmedl.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JDSMAA00013300 [...]