Advertisement

Model-based control system design in a urea-SCR aftertreatment system based on NH3 sensor feedback

  • M. DevarakondaEmail author
  • G. Parker
  • J. H. Johnson
  • V. Strots
Article

Abstract

This paper presents preliminary control system simulation results in a urea-selective catalytic reduction (SCR) aftertreatment system based on NH3 sensor feedback. A four-state control-oriented lumped parameter model is used to analyze the controllability and observability properties of the urea-SCR plant. A model-based estimator is designed via simulation and a control system is developed with design based on a sliding mode control framework. The control system based on NH3 sensor feedback is analyzed via simulation by comparing it to a control system developed based on NOx sensor feedback. Simulation results show that the NH3 sensor-based strategy performs very similarly in comparison to a NOx sensor-based strategy. The control system performance metrics for NOx index, urea index, urea usage, and NH3 slip suggest that the NOx sensor can be a potential alternative to a NOx sensor for urea-SCR control applications.

Key Words

Urea-SCR catalyst Model-based estimation Observer Control system design NH3 sensor Sliding mode control 

References

  1. Czerwsinki, J., Peterman, J., Comte, P., Lemaire, J. and Mayer, A. (2007). Diesel NO/NO2/NOx emissions — New experiences and challenges. SAE Paper No. 2007-01-0321.Google Scholar
  2. Devadas, M., Krocher, O. and Wokaun, A. (2005). Catalytic investigation of Fe-ZSM5 in the selective catalytic reduction of NOx with NH3. Reaction Kinetics and Catalysis Letters, 86, 347–354.CrossRefGoogle Scholar
  3. Devadas, M., Krocher, O., Elsener, M., Wokaun, A., Soger, N., Pfeifer, M., Demel, Y. and Mussmann, L. (2006). Influence of NO2 on the selective catalytic reduction of NO with NH3 over Fe-ZSM5. Applied Catalysis B: Environmental, 67, 187–196.CrossRefGoogle Scholar
  4. Devarakonda, M. N., (2008c). Dynamic Modeling, Simulation and Development of Model Based Control Strategies in a Urea-SCR Aftertreatment System for Heavy Duty Diesel Engines. Ph.D. Dissertation. Michigan Tech University.Google Scholar
  5. Devarakonda, M., Parker, G., Johnson, J. H. and Strots, V. (2008d). Simulation based control system analysis of a urea SCR aftertreatment system based on NH3 sensor feedback. Cross-cut Lean Exhaust Emissions Reduction Simullation (CLEERS) Workshop. www.cleers.org.
  6. Devarakonda, M., Parker, G., Johnson, J. H., Strots, V. and Santhanam, S. (2008a). Adequacy of reduced order models for model based control in a urea-SCR aftertreatment system. SAE Paper No. 2008-01-0617 (Also accepted as a special publication in SP-2155).Google Scholar
  7. Devarakonda, M., Parker, G., Johnson, J. H., Strots, V. and Santhanam, S. (2008b). Model based estimation and control strategy development for urea-SCR aftertreatment system. Int. J. Fuels and Lubricants 1,1, 646–661.Google Scholar
  8. Krocher, O., Devadas, M., Elsener, M., Wokaun, A., Soger, N., Pfeifer, M., Demel, Y. and Mussmann, L. (2006). Investigation of the selective catalytic reduction of NO by NH3 on Fe-ZSM5 monolith catalysts. Applied Catalysis B: Environmental, 66, 208–216.CrossRefGoogle Scholar
  9. Moss, R., Muller, R., Plog, C., Knezevic, A., Leye, H., Irion, E., Braun, T., Marquardt, K. and Binder, K. (2002). Selective ammonia exhaust gas sensor for automotive applications. Sensors and Actuators B, 83, 181–189.CrossRefGoogle Scholar
  10. Schar, C., Onder, C. and Geering, H. (2006). Control of an SCR catalytic converter system for heavy duty diesel application. IEEE Trans. Control Systems Technology, 14, 641–654.CrossRefGoogle Scholar
  11. Tronconi, E., Lietti, L., Forzatti, P. and Malloggi, S. (1996). Experimental and theoretical investigation of the dynamics of the SCR-DeNOx reaction. Chemical Engineering Science, 51, 2965–2970.CrossRefGoogle Scholar
  12. Tronconi, E., Nova, I., Grossale, A. and Ciardelli, C. (2007). Catalytic mechanism, detailed kinetics and converter model for NH3-SCR of NOx emissions from vehicles. Cross-cut Lean Exhaust Emissions Reduction Simulation (CLEERS) Workshop. www.cleers.org.
  13. Upadhyay, D. and Van Nieuwstadt (2002). Control design of an automotive urea SCR catalyst. ASME Int. Mechanical Engineering Cong. and Exposition, IMECE2002-32103.Google Scholar
  14. Upadhyay, D. and Van Nieuwstadt, M. (2006). Model based analysis and control design of a Urea-SCR DeNOx aftertreatment system. ASME J. Dynamic Systems, Measurement and Control, 128.Google Scholar
  15. Wang, D., Tao, S., Cabush, D. and Racine, D. (2007). Ammonia sensor for SCR NOx reduction. Diesel Engines Emissions Reduction (DEER) Conf. Google Scholar
  16. Wingbrant, H., Svenningstorp, H., Salomonsson, P., Kubinski, D., Visser, J., Lofdahl, M. and Spetz, A. (2005). Using a MISic-FET sensor for detecting NH3 in SCR systems. IEEE Sensors J., 5, 1099–1105.CrossRefGoogle Scholar

Copyright information

© The Korean Society of Automotive Engineers and Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  • M. Devarakonda
    • 1
    Email author
  • G. Parker
    • 1
  • J. H. Johnson
    • 1
  • V. Strots
    • 2
  1. 1.ME-EM DepartmentMichigan Technological UniversityHoughtonUSA
  2. 2.Advanced Aftertreatment TechnologiesNavistar IncMelrose ParkUSA

Personalised recommendations