Is closed-loop SCR control required to meet future emission targets?

F.P.T. Willems; R.P.M. Cloudt; E.A.C. Eijnden, van den; M.H.P. Genderen, van; R. Verbeek; A.G. Jager, de; W. Boomsma; I.T.M. van den Heuvel

Is closed-loop SCR control required to meet future emission targets?

F.P.T. Willems, R.P.M. Cloudt, E.A.C. Eijnden, van den, M.H.P. Genderen, van, R. Verbeek, A.G. Jager, de, W. Boomsma, I.T.M. van den Heuvel

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution › Academic › peer-review

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Abstract

To meet 2010 emission targets, optimal SCR systemperformance is required. In addition, attention has to bepaid to in-use compliance requirements. Closed-loopcontrol seems an attractive option to meet the formulatedgoals. This study deals with the potential and limitationsof closed-loop SCR control.High NOx conversion in combination with acceptable NH3slip can be realized with an open-loop control strategy.However, closed-loop control is needed to make theSCR system robust for urea dosage inaccuracy, catalystageing and NOx engine-out variations. Then, the systemmeets conformity of production and in-use compliancenorms.To demonstrate the potential of closed-loop SCR control,a NOx sensor based control strategy with cross-sensitivity compensation is compared with an adaptivesurface coverage/NH3 slip control strategy and an open-loop strategy. The adaptive surface coverage/NH3 slipcontrol strategy shows best performance over simulatedESC and ETC cycles.SCR catalyst dynamics, time delay in the urea injectionand maximum NH3 slip targets limit the performance ofclosed-loop SCR control. If new reagent dosage systemsand future catalyst technology are able to relieve theselimitations, closed-loop control has the potential toreduce the calibration effort and to improve the transientcontrol performance.

Original language	English
Title of host publication	Proceedings of the SAE World Congress & Exhibition 2007, Detroit, Michigan, USA
Publication status	Published - 2007
Event	SAE 2007 World Congress and Exhibition - Cobo Center, Detroit, United States Duration: 16 Apr 2007 → 19 Apr 2007

Conference

Conference	SAE 2007 World Congress and Exhibition
Country/Territory	United States
City	Detroit
Period	16/04/07 → 19/04/07
Other

Cite this

@inproceedings{ee2d9044b2924f0988677c56273ab2be,

title = "Is closed-loop SCR control required to meet future emission targets?",

abstract = "To meet 2010 emission targets, optimal SCR systemperformance is required. In addition, attention has to bepaid to in-use compliance requirements. Closed-loopcontrol seems an attractive option to meet the formulatedgoals. This study deals with the potential and limitationsof closed-loop SCR control.High NOx conversion in combination with acceptable NH3slip can be realized with an open-loop control strategy.However, closed-loop control is needed to make theSCR system robust for urea dosage inaccuracy, catalystageing and NOx engine-out variations. Then, the systemmeets conformity of production and in-use compliancenorms.To demonstrate the potential of closed-loop SCR control,a NOx sensor based control strategy with cross-sensitivity compensation is compared with an adaptivesurface coverage/NH3 slip control strategy and an open-loop strategy. The adaptive surface coverage/NH3 slipcontrol strategy shows best performance over simulatedESC and ETC cycles.SCR catalyst dynamics, time delay in the urea injectionand maximum NH3 slip targets limit the performance ofclosed-loop SCR control. If new reagent dosage systemsand future catalyst technology are able to relieve theselimitations, closed-loop control has the potential toreduce the calibration effort and to improve the transientcontrol performance.",

author = "F.P.T. Willems and R.P.M. Cloudt and {Eijnden, van den}, E.A.C. and {Genderen, van}, M.H.P. and R. Verbeek and {Jager, de}, A.G. and W. Boomsma and {van den Heuvel}, I.T.M.",

year = "2007",

language = "English",

booktitle = "Proceedings of the SAE World Congress & Exhibition 2007, Detroit, Michigan, USA",

note = "SAE 2007 World Congress and Exhibition ; Conference date: 16-04-2007 Through 19-04-2007",

}

Willems, FPT, Cloudt, RPM, Eijnden, van den, EAC, Genderen, van, MHP, Verbeek, R, Jager, de, AG, Boomsma, W & van den Heuvel, ITM 2007, Is closed-loop SCR control required to meet future emission targets? in Proceedings of the SAE World Congress & Exhibition 2007, Detroit, Michigan, USA. SAE 2007 World Congress and Exhibition, Detroit, Michigan, United States, 16/04/07.