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Detection of Injected Urea Quantity and Correction for SCR Urea Dosing Control
Technical Paper
2015-01-1038
ISSN: 0148-7191, e-ISSN: 2688-3627
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English
Abstract
Using urea-based Selected Catalytic Reduction (SCR) systems is an effective way in diesel engine after-treatment systems to meet increasingly stringent emission regulations. The amount of urea injection is critical to achieve high NOx reduction efficiency and low ammonia slip and overdosing or under-dosing of urea injection need to be avoided. One of the difficulties in urea injection amount control lies in the accurate measurement/estimation of the urea injection mass. To effectively address this issue, this paper defined a correction factor for under-dosing or overdosing detection and correction and proposed two methods to identify the correction factor. The first method is based on urea pump model and line pressure. Through frequency analysis, the relation between the urea pump speed and power spectrum characteristics of the line pressure by using FFT method was revealed. The urea pump frequency is extracted from the frequency analysis of the line pressure and used for detecting the urea injection and identifying the correction factor. Second method is based on the effective voltage of the Motor. The relation between urea injection and effective voltage of the Motor was revealed based on the motor dynamic model. The effective voltage of the Motor is used to detect the urea injection and identify the correction factor. The effectiveness of both proposed detection and correction methods are experimentally validated through the urea dosing system.
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Citation
Ning, J. and Yan, F., "Detection of Injected Urea Quantity and Correction for SCR Urea Dosing Control," SAE Technical Paper 2015-01-1038, 2015, https://doi.org/10.4271/2015-01-1038.Also In
References
- World Health Organization WHO Air Quality Guidelines for Particulate Matter, Ozone, Nitrogen Dioxide, and Sulfur Dioxide: Global Update 2005 Geneva, Switzerland WHO Press 2006
- Backman , H. , Arve , K. , Klingstedt , F. , and Murzin , D. Y. Kinetic considerations of H2 assisted hydrocarbon selective catalytic reduction of NO over Ag/Al2O3: II. Kinetic modeling Applied Catalysis 304 86 92 2006
- Hsieh , M.F. and Wang , J. An Extended Kalman Filter for Ammonia Coverage Ratio and Capacity Estimations in the Application of Diesel Engine SCR Control and Onboard Diagnosis American Control Conference 2010
- Johnson , T. Review of Diesel Emissions and Control SAE Int. J. Fuels Lubr. 3 1 16 29 2010 10.4271/2010-01-0301
- Shost , M. , Noetzel , J. , Wu , M. , Sugiarto , T. et al. Monitoring, Feedback and Control of Urea SCR Dosing Systems for NOx Reduction: Utilizing an Embedded Model and Ammonia Sensing SAE Technical Paper 2008-01-1325 2008 10.4271/2008-01-1325
- Hofmann , L. , Rusch , K. , Fischer , S. , and Lemire , B. Onboard Emissions Monitoring on a HD Truck with an SCR System Using Nox Sensors SAE Technical Paper 2004-01-1290 2004 10.4271/2004-01-1290
- Sun , Y. , Wang , Y. , Chang , C. , and Levijoki , S. Detection of Urea Injection System Faults for SCR Systems SAE Technical Paper 2012-01-0431 2012 10.4271/2012-01-0431
- Wang , Y.Y. , Sun , Y. and Gady , K. Model-Based Estimation of Injected Urea Quantity and Diagnostic for SCR Urea Injection System American Control Conference 2012