Documents disponibles écrits par cet auteur

An integrated fault detection and isolation and safe-parking framework for networked process systems / Miao Du in Industrial & engineering chemistry research, Vol. 50 N° 9 (Mai 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 9 (Mai 2011) . - pp. 5667–5679 Titre : An integrated fault detection and isolation and safe-parking framework for networked process systems Type de document : texte imprimé Auteurs : Miao Du, Auteur ; Rahul Gandhi, Auteur ; Prashant Mhaskar, Auteur Année de publication : 2011 Article en page(s) : pp. 5667–5679 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Detection  Isolation Résumé : This work considers the problem of fault detection and isolation (FDI) and fault-handling for networked process systems subject to actuator faults. Multiple units are interconnected in the context of a networked plant. It is assumed that the failed actuator reverts to its fail-safe position and precludes the possibility of nominal operation in the affected unit. First, a robust FDI design is presented, where relations between the prescribed inputs and state measurements in the absence of faults are constructed with the consideration of uncertainty by using the process model. A fault is detected and isolated when the corresponding relation is violated. Then, an algorithm is developed to generalize the safe-parking approach (maintaining the process at an appropriate temporary operating point, which is called a safe-park point, during fault rectification) for fault-tolerant control to account for complex interconnections such as parallel and recycle streams in networked process systems. In particular, it can determine the units that need to be safe-parked during fault rectification and generate possible safe-park points for these units. The efficacy of the integrated FDI and safe-parking framework is demonstrated on a chemical process example comprising three reactors and a separator. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101786t [article] An integrated fault detection and isolation and safe-parking framework for networked process systems [texte imprimé] / Miao Du, Auteur ; Rahul Gandhi, Auteur ; Prashant Mhaskar, Auteur . - 2011 . - pp. 5667–5679. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 9 (Mai 2011) . - pp. 5667–5679 Mots-clés : Detection  Isolation Résumé : This work considers the problem of fault detection and isolation (FDI) and fault-handling for networked process systems subject to actuator faults. Multiple units are interconnected in the context of a networked plant. It is assumed that the failed actuator reverts to its fail-safe position and precludes the possibility of nominal operation in the affected unit. First, a robust FDI design is presented, where relations between the prescribed inputs and state measurements in the absence of faults are constructed with the consideration of uncertainty by using the process model. A fault is detected and isolated when the corresponding relation is violated. Then, an algorithm is developed to generalize the safe-parking approach (maintaining the process at an appropriate temporary operating point, which is called a safe-park point, during fault rectification) for fault-tolerant control to account for complex interconnections such as parallel and recycle streams in networked process systems. In particular, it can determine the units that need to be safe-parked during fault rectification and generate possible safe-park points for these units. The efficacy of the integrated FDI and safe-parking framework is demonstrated on a chemical process example comprising three reactors and a separator. DEWEY : 660 ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie101786t

Safe-parking of a styrene polymerization process / Rahul Gandhi in Industrial & engineering chemistry research, Vol. 48 N° 15 (Août 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 15 (Août 2009) . - pp. 7205–7213 Titre : Safe-parking of a styrene polymerization process Type de document : texte imprimé Auteurs : Rahul Gandhi, Auteur ; Dave Baldwin, Auteur ; Prashant Mhaskar, Auteur Année de publication : 2009 Article en page(s) : pp. 7205–7213 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Nitroxide-mediated  radical  polymerization  Styrene  Lyapunov  based  model  Monomer  feed  streams Résumé : This work considers the problem of control and fault-handling in living nitroxide-mediated radical polymerization (NMRP) of styrene subject to input constraints. First, a Lyapunov based model predictive controller is designed that allows for an explicit computation of the stability region. Next, a fault in one of the monomer feed streams is considered due to which operation of the reactor at the nominal operating point is no longer possible. It is shown that trying to continue nominal operation using the remaining functioning actuator drives the process to a point resulting in significantly off-spec product. A safe-parking framework is utilized to choose an operating point during fault rectification so that the styrene produced during fault rectification complies with the desired product specifications, and smooth resumption of nominal operation upon fault rectification is achieved. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8019938 [article] Safe-parking of a styrene polymerization process [texte imprimé] / Rahul Gandhi, Auteur ; Dave Baldwin, Auteur ; Prashant Mhaskar, Auteur . - 2009 . - pp. 7205–7213. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 15 (Août 2009) . - pp. 7205–7213 Mots-clés : Nitroxide-mediated  radical  polymerization  Styrene  Lyapunov  based  model  Monomer  feed  streams Résumé : This work considers the problem of control and fault-handling in living nitroxide-mediated radical polymerization (NMRP) of styrene subject to input constraints. First, a Lyapunov based model predictive controller is designed that allows for an explicit computation of the stability region. Next, a fault in one of the monomer feed streams is considered due to which operation of the reactor at the nominal operating point is no longer possible. It is shown that trying to continue nominal operation using the remaining functioning actuator drives the process to a point resulting in significantly off-spec product. A safe-parking framework is utilized to choose an operating point during fault rectification so that the styrene produced during fault rectification complies with the desired product specifications, and smooth resumption of nominal operation upon fault rectification is achieved. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8019938