US 12,436,065 B2
Method and device for measuring nitrogen oxide and ammonia emissions from an exhaust gas aftertreatment system for combustion exhaust gases
Thomas Zein, Sindelfingen (DE); Yunjie Lian, Markgroeningen (DE); Frank Meier, Stuttgart (DE); and Gunther Kegel, Rutesheim (DE)
Assigned to ROBERT BOSCH GMBH, Stuttgart (DE)
Filed by Robert Bosch GmbH, Stuttgart (DE)
Filed on Dec. 7, 2023, as Appl. No. 18/532,094.
Claims priority of application No. 10 2022 214 379.5 (DE), filed on Dec. 23, 2022.
Prior Publication US 2024/0210280 A1, Jun. 27, 2024
Int. Cl. F01N 11/00 (2006.01); F01N 9/00 (2006.01); G01M 15/10 (2006.01)
CPC G01M 15/102 (2013.01) [F01N 9/005 (2013.01); F01N 11/00 (2013.01); F01N 11/007 (2013.01); F01N 2550/02 (2013.01); F01N 2560/021 (2013.01); F01N 2560/026 (2013.01); F01N 2900/1402 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A control method for an internal combustion engine that is part of a system that includes an exhaust gas aftertreatment system and an output-side nitrogen oxide sensor, the exhaust gas aftertreatment system including multiple catalytic converter segments that (I) form a single catalytic converter, (II) are arranged in series along an exhaust gas flow path of exhaust gas output from the internal combustion engine, (III) are each structured to perform a catalytic reduction reaction by which nitrogen oxide is at least partially convertible into ammonia, and (IV) are structured and arranged such that (i) a respective extent of nitrogen oxide conversion within each of the catalytic converter segments depends on respective local operating conditions at the respective segment at the time of the respective conversion by the respective segment, and (ii) for each of those of the segments that are downstream, with respect to the exhaust gas flow path, from at least one other of the segments, the respective extent of the nitrogen oxide conversion by the respective segment further depends on a respective composition of exhaust gas output from an immediately adjacent upstream one of the segments, the method comprising the following steps:
obtaining a measurement signal from the output-side nitrogen oxide sensor;
ascertaining a partial conversion indication for each of the multiple catalytic converter segments using a conversion model based on the respective local operating conditions, wherein:
the conversion model separately models respective conversion characteristics of each of the catalytic converter segments; and
for each of those of the segments that are downstream, with respect to said exhaust gas flow, from at least one other of said segments, the modeling of the respective conversion characteristics of the respective catalytic converter segment takes into consideration respective output of the modeling by the conversion model of the immediately adjacent upstream one of the segments;
determining a combined conversion indication that is indicated by the measurement signal from the output-side nitrogen oxide sensor based on the multiple partial conversion indications, wherein the determination of the combined conversion indication includes ascertaining respective total amounts of nitrogen oxide emission and ammonia emission in output exhaust gas at and sensed by the nitrogen oxide sensor; and
controlling operation of the internal combustion engine based on the determined respective amounts of nitrogen oxide and ammonia emissions.