Cycle-Driven Optimization of a Fixed-Structure Controller for Urea
Dosing in a Mobile SCR System 2020-01-5106
A model-based urea-dosing controller has been developed for the selective
catalytic reduction (SCR) units on a diesel engine exhaust aftertreatment system
(EATS). The SCR units consist of an integrated SCR-coated filter and then
followed by a flow-through SCR catalyst. The controller was developed based on
an analysis of the data generated from a Millbrook London Transport Bus (MLTB)
test cycle fed into a validated model of the SCR-filter and SCR units. The
critical system parameters that showed strong correlation with outlet nitrogen
oxides (NOx) and ammonia (NH3) emissions were first
identified, and then the sensitivity of those parameters was analyzed. The most
sensitive system parameters were configured as the controller gain parameters. A
proportional controller based on the key parameters with optimized gains
settings for the MLTB cycle delivered over a 10% reduction in cumulative
NOx emission over the cycle compared to a fixed
NH3/NOx ratio (ANR) controller. The controller was
shown to be robust to errors in sensor measurement in that it delivered
significantly less variation in performance compared to a fixed ANR
controller.
Citation: Olowojebutu, S. and Steffen, T., "Cycle-Driven Optimization of a Fixed-Structure Controller for Urea Dosing in a Mobile SCR System," SAE Technical Paper 2020-01-5106, 2020, https://doi.org/10.4271/2020-01-5106. Download Citation
Author(s):
Seun Olowojebutu, Thomas Steffen
Affiliated:
Loughborough University
Pages: 13
Event:
Automotive Technical Papers
ISSN:
0148-7191
e-ISSN:
2688-3627
Related Topics:
Selective catalytic reduction
Nitrogen oxides
Diesel / compression ignition engines
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