This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Model Predictive Control of a Combined EGR/SCR HD Diesel Engine
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 12, 2010 by SAE International in United States
This content contains downloadable datasetsAnnotation ability available
Achieving upcoming HD emissions legislation, Euro VI/EPA 10, is a challenge for all engine manufacturers. A likely solution to meet the NOx limit is to use a combination of EGR and SCR. Combining these two technologies poses new challenges and possibilities when it comes to optimization and calibration.
Using a complete system approach, i.e., considering the engine and the aftertreatment system as a single unit, is important in order to achieve good performance. Optimizing the complete system is a tedious task; first there are a large number of variables which affect both emissions and fuel consumption (injection timing, EGR rate, urea dosing, injection pressure, pilot/post injections, for example). Secondly, the chemical reactions in the SCR catalyst are substantially slower than the dynamics of the diesel engine and the rest of the system, making the optimization problem time dependent.
The engine studied is a 13-liter heavy-duty diesel engine equipped with a vanadia-based SCR system. The diesel engine uses common rail fuel injection, a variable geometry turbocharger (VGT) and cooled EGR.
In this paper, a Model Predictive Control (MPC) application is presented. The controller minimizes brake specific fuel consumption (including urea cost) by simultaneously optimizing engine out NOx and urea dosing, while maintaining emissions at Euro VI levels. The MPC is applied to the World Harmonized Test Cycles (WHSC/WHTC). Improvements in both fuel economy and emissions can be achieved by using the optimization/control method suggested.
CitationWesterlund, C., Westerberg, B., Odenbrand, I., and Egnell, R., "Model Predictive Control of a Combined EGR/SCR HD Diesel Engine," SAE Technical Paper 2010-01-1175, 2010, https://doi.org/10.4271/2010-01-1175.
Data Sets - Support Documents
|Unnamed Dataset 1|
|Unnamed Dataset 2|
|Unnamed Dataset 3|
- Devarakonda, M. Parker, G. Johnson, J.H. Strots, V. et al. “Model-Based Estimation and Control System Development in a Urea-SCR Aftertreatment System,” SAE Technical Paper 2008-01-1324 2008
- Schär C.M. Onder C.H. Elsener M. Geering, H. P. “Model-based Control of an SCR System for Mobile Application” F2004V205 Proceedings of World Automotive Congress, FISITA 2004 2004
- Ericson, C. Westerberg, B. Andersson, M. Egnell, R. “Modelling Diesel Engine Combustion and NO x Formation for Model Based Control and Simulation of Engine and Exhaust Aftertreatment Systems,” SAE Technical Paper 2006-01-0687 2006
- Ericson, C. Westerberg, B. Odenbrand, I. “A State-Space Simplified SCR Catalyst Model for Real Time Applications,” SAE Technical Paper 2008-01-0616 2008
- Ericson, C. Westerberg, B. Odenbrand, I. Egnell, R. “Characterisation and Model Based Optimization of a Complete Diesel Engine / SCR System,” SAE Technical Paper 2009-01-0896 2009
- Gill P.E. Murray W. Saunders, M.A. “User's Guide for SNOPT Version 7: Software for Large-Scale Nonlinear Programming” 2007
- Hellström, E. Fröberg, A. Nielsen, L. “A Real-Time Fuel-Optimal Cruise Controller for Heavy Trucks Using Road Topography Information,” SAE Technical Paper 2006-01-0008 2006
- Andersson, M. Johansson, B. Hultqvist, A. Noehre C. “A Predictive Real Time NOx Model for Conventional and Partially Premixed Combustion,” SAE Technical Paper 2006-01-3329 2006
- Eriksson, L. “Mean Value Models for Exhaust System Temperatures,” SAE Technical Paper 2002-01-0374 2002
- Siebers D.L. “Liquid-Phase Fuel Penetration in Diesel Sprays,” SAE Technical Paper 980809 1998
- Chatterjee, D. Burkhardt, T. Rappe, T. Güthenke A. et al. “Numerical Simulation of DOC+DPF+SCR Systems: DOC Influence on SCR Performance,” SAE Int. J. Fuels Lubr. 1 1 440 451 2008
- Bird R. B. Stewart W. E. Lightfoot E. N. “Transport phenomena” John Wiley & Sons Singapore 1960 542 546
- Fogler, H. S. “Elements of Chemical Reaction Engineering” Prentice Hall PTR 2000 967