DE102010034983A1 - Method for detecting current state of exhaust after-treatment system in e.g. motor car, involves determining measured variables in different frequency ranges to allow measuring device to provide conclusions about memory state - Google Patents

Method for detecting current state of exhaust after-treatment system in e.g. motor car, involves determining measured variables in different frequency ranges to allow measuring device to provide conclusions about memory state Download PDF

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DE102010034983A1
DE102010034983A1 DE102010034983A DE102010034983A DE102010034983A1 DE 102010034983 A1 DE102010034983 A1 DE 102010034983A1 DE 102010034983 A DE102010034983 A DE 102010034983A DE 102010034983 A DE102010034983 A DE 102010034983A DE 102010034983 A1 DE102010034983 A1 DE 102010034983A1
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frequency ranges
state
measuring device
exhaust
measured variables
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Anmelder Gleich
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FISCHERAUER, GERHARD, PROF. DR.-ING., DE
MOOS, RALF, PROF. DR.-ING., DE
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/18—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
    • F01N3/20—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion ; Methods of operation or control of catalytic converters
    • F01N3/2066—Selective catalytic reduction [SCR]
    • F01N3/208—Control of selective catalytic reduction [SCR], e.g. dosing of reducing agent
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N22/00—Investigating or analysing materials by the use of microwaves or radio waves, i.e. electromagnetic waves with a wavelength of one millimetre or more
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2560/00—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics
    • F01N2560/02—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics the means being an exhaust gas sensor
    • F01N2560/021—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics the means being an exhaust gas sensor for measuring or detecting ammonia NH3
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2560/00—Exhaust systems with means for detecting or measuring exhaust gas components or characteristics
    • F01N2560/12—Other sensor principles, e.g. using electro conductivity of substrate or radio frequency
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
    • Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies

Abstract

The method involves propagating electromagnetic waves in a metallic housing (2), where the waves are interfered by a state of catalyst systems. The metallic housing is arranged in a selective-catalytic-reduction (SCR)-catalyzer (1). Measured variables such as reflectance factor amount and resonance frequency difference, are determined in different frequency ranges to allow a measuring device to provide conclusions about a memory state under consideration of transverse influences.

Description

Stand der TechnikState of the art

Abgase aus magerbetriebenen Verbrennungsmotoren wie z. B. Dieselmotoren werden derzeit mit Hilfe verschiedener Verfahren nachbehandelt, um die im Abgas vorhandenen Stickoxide (NOx) zu reduzieren. Zum Beispiel werden sog. NOx-Speicherkatalysatoren (NSK, auch Lean-NOx-Trap) oder Ammoniak-SCR-Systeme eingesetzt [ D. Y. Wang, S. Yao, M. Shost, J. Yoo, D. Cabush, D. Racine, R. Cloudt, F. Willems: Ammonia sensor for Closed-Loop SCR Control. SAE paper 2008-01-0919 (2008) ]. Während bei NOx-Speicherkatalysatoren Stickoxide im Magerbetrieb eingespeichert und durch eine kurze Fettphase des Motors regeneriert werden, wird für Ammoniak-SCR-Systeme die separate Zudosierung einer ammoniakbildenden Verbindung ins Abgas benötigt. Dies geschieht derzeit vor allem in der Form einer Harnstoff-Wasser-Lösung, die im SCR-Katalysator zunächst zu NH3 umgesetzt wird. Im SCR-Katalysator werden dann auch die Stickoxide mit dem entstandenen Reduktionsmittel Ammoniak zu Stickstoff und Wasser umgesetzt. Um diese sog. NH3-SCR-Reaktionen durchzuführen, wird im SCR-Katalysator Ammoniak eingespeichert. Bedingt durch den Reaktionsmechanismus ermöglicht erst die Ammoniakeinspeicherung die NOx-Konversion. Den Ammoniakbeladungsgrad zu bestimmen, ist äußerst schwierig, da er nicht nur von der Temperatur sondern auch vom Gasfluss und von Konzentrationen von Abgasbestandteilen wie NH3, NO, NO2, H2O usw. abhängt. Weiterhin spielt die aktuelle Umsatzrate und der Alterungszustand des SCR-Katalysators eine Rolle.Exhaust gases from lean-burn internal combustion engines such. B. Diesel engines are currently being treated by various methods to reduce existing in the exhaust gas oxides (NO x ). For example, so-called NO x storage catalysts (NSK, also Lean NO x -Trap) or ammonia SCR systems are used [ DY Wang, S. Yao, M. Shost, J. Yoo, D. Cabush, D. Racine, R. Cloudt, F. Willems: Ammonia sensor for closed-loop SCR control. SAE paper 2008-01-0919 (2008) ]. While nitrogen oxides are stored in lean operation in NO x storage catalysts and regenerated by a short rich phase of the engine, for ammonia-SCR systems the separate addition of an ammonia-forming compound into the exhaust gas is required. At present, this is mainly done in the form of a urea-water solution, which is first converted to NH 3 in the SCR catalyst. In the SCR catalyst, the nitrogen oxides are then reacted with the resulting reducing agent ammonia to nitrogen and water. To carry out these so-called NH 3 -SCR reactions, ammonia is stored in the SCR catalyst. Due to the reaction mechanism, it is the ammonia storage that enables NO x conversion. Determining the degree of ammonia loading is extremely difficult because it depends not only on the temperature but also on the gas flow and concentrations of exhaust gas constituents such as NH 3 , NO, NO 2 , H 2 O, etc. Furthermore, the current conversion rate and the aging state of the SCR catalyst plays a role.

Die Regelung stellt dabei eine besondere Herausforderung dar, da eine möglichst vollständige Umsetzung der Stickoxide, aber dabei kein Durchbruch von NH3 erfolgen soll. Aktuell besteht die Möglichkeit, einen NOx- oder NH3-Sensor nach Katalysator einzusetzen und damit die Gaskonzentrationen nach Katalysator zu bestimmen. Eine Nachregelung der Dosierung der Harnstoff-Wasser-Lösung ist mit diesem Verfahren aber erst möglich, wenn bereits ein NH3-Schlupf nach Katalysator aufgetreten ist. Wesentlich besser wäre eine Information über den aktuellen Speicherzustand des gesamten Katalysators.The regulation represents a special challenge, since as complete a conversion as possible of the nitrogen oxides, but no breakthrough of NH 3 should take place. Currently, it is possible to use a NO x or NH 3 sensor after catalyst and thus to determine the gas concentrations by catalyst. A readjustment of the dosage of the urea-water solution is only possible with this method, if an NH 3 -slip after catalyst has already occurred. Much better would be information about the current memory state of the entire catalyst.

Es wird in der DE 103 58 495 A1 und in der DE 10 2008 012 050 A1 vorgeschlagen, diese indirekte Überwachung durch eine Hochfrequenzmessung als direkte Messung des Katalysators bzw. des Katalysator-Werkstoffs selbst zu ersetzen. Die Veränderungen des Katalysatorzustands zeigen sich in den elektrischen Eigenschaften des Katalysatormaterials und können über die Störung der Ausbreitung elektromagnetischer Wellen in einem Hohlleiter charakterisiert werden. Der Hohlleiter wird hier durch das Gehäuse des Katalysators oder Filters gebildet. Für Dieselpartikelfilter im Speziellen ist die Hochfrequenzmessung auch in US 4,477,771 oder US 5,497,099 vorgeschlagen.It will be in the DE 103 58 495 A1 and in the DE 10 2008 012 050 A1 proposed to replace this indirect monitoring by a high frequency measurement as a direct measurement of the catalyst or the catalyst material itself. The changes in the state of the catalyst are reflected in the electrical properties of the catalyst material and can be characterized by the disturbance of the propagation of electromagnetic waves in a waveguide. The waveguide is formed here by the housing of the catalyst or filter. For diesel particulate filters in particular, the high frequency measurement is also in US 4,477,771 or US 5,497,099 proposed.

Die o. g. Verfahren nutzen die Änderungen der elektrischen Eigenschaften der Komponenten des Abgasnachbehandlungssystems während des Betriebs. Diese Änderungen basieren auf der physikochemischen Wechselwirkung des Katalysatormaterials mit den Gasbestandteilen im Abgas. Diese Änderungen wirken sich auf die Ausbreitung der elektromagnetischen Wellen innerhalb des Gehäuses aus. Das Gehäuse des Katalysators oder Filters wirkt als Hohlraumresonator und bietet die Möglichkeit der Einkopplung stehender Wellen in das System. Somit folgt z. B. eine höhere Dämpfung oder eine Verschiebung von Resonanzfrequenzen bei Zustandsänderung. Die Messung des Systems kann kontaktlos über eine kapazitive oder induktive Ankopplung in Form einer Stab- oder Schleifenantenne erfolgen.The o. G. Methods utilize the changes in the electrical properties of the exhaust after-treatment system components during operation. These changes are based on the physicochemical interaction of the catalyst material with the gas constituents in the exhaust gas. These changes affect the propagation of electromagnetic waves within the housing. The housing of the catalyst or filter acts as a cavity resonator and offers the possibility of coupling standing waves into the system. Thus follows z. B. a higher attenuation or a shift of resonance frequencies at change of state. The measurement of the system can be made contactless via a capacitive or inductive coupling in the form of a rod or loop antenna.

Die elektrischen Eigenschaften des SCR-Katalysators werden in erster Linie durch die Einspeicherung von Ammoniak im Katalysator verändert. Diese Beladung stellt die gewünschte Messgröße dar.The electrical properties of the SCR catalyst are changed primarily by the storage of ammonia in the catalyst. This loading represents the desired measured quantity.

Eine Messung des Speicherzustandes kann durch die Menge gespeicherten Wassers oder anderer Komponenten, aber auch durch den Wassergehalt des Abgases oder durch andere Abgasbestandteile beeinflusst werden.A measurement of the storage state can be influenced by the amount of stored water or other components, but also by the water content of the exhaust gas or by other exhaust gas constituents.

Aufgabenstellungtask

Die Aufgabe der vorliegenden Erfindung besteht darin, eine Möglichkeit zu schaffen, durch ein einfaches Messsystem den aktuellen Speicherzustand eines NH3-Speicherkatalysators zu überwachen. Die Messeinrichtung soll zum Beispiel kontinuierlich im Realabgas eines Fahrzeugs eingesetzt werden können.The object of the present invention is to provide a way to monitor by a simple measuring system, the current storage state of a NH 3 storage catalytic converter. For example, the measuring device should be able to be used continuously in the real exhaust gas of a vehicle.

Unter dem Begriff Messeinrichtung ist in diesem Zusammenhang zu verstehen: Eine Sonde zur Einkopplung elektromagnetischer Wellen inkl. der entsprechenden Elektronik für die Einprägung und Messung der reflektierten Wellen (Reflexionsmessung) oder zwei Sonden inkl. entsprechender Elektronik für die Einprägung elektromagnetischer Wellen und Messung der reflektierten bzw. an der zweiten Sonde ankommenden Wellen (Transmissionsmessung).In this context, the term measuring device is to be understood as meaning: a probe for coupling in electromagnetic waves, including the corresponding electronics for impressing and measuring the reflected waves (reflection measurement) or two probes, including corresponding electronics for the embossing electromagnetic waves and measurement of the reflected or arriving at the second probe waves (transmission measurement).

Lösung der AufgabeSolution of the task

Aufbauend auf den Schriften DE 103 58 495 A1 , DE 10 2008 012 050 A1 und US 4,477,771 wird hier vorgeschlagen, dass die Beladungserkennung eines SCR-Abgasnachbehandlungssystems sehr gut durch die Messung in mindestens zwei Frequenzbereichen, z. B. durch die Ermittlung mehrerer Resonanzfrequenzen in der Messung von Reflexions- oder Transmissionsparametern erfolgen kann. Es werden dazu eine oder zwei Feldsonden benötigt.Building on the scriptures DE 103 58 495 A1 . DE 10 2008 012 050 A1 and US 4,477,771 It is proposed here that the load detection of an SCR exhaust aftertreatment system very well by the measurement in at least two frequency ranges, eg. B. can be done by the determination of several resonance frequencies in the measurement of reflection or transmission parameters. One or two field probes are needed.

Für eine möglichst genaue Aussage über den Grad der NH3-Beladung bietet die Hochfrequenzmessung die Möglichkeit der Betrachtung mehrerer Frequenzbereiche. Dabei wird ausgenutzt, dass sich die Änderungen des Signals durch die NH3-Beladung im Vergleich zu den Quereinflüssen in unterschiedlichen Frequenzbereichen verschiedenartig auswirken. Somit kann durch Korrelation der Effekte in verschiedenen Frequenzbereichen der Einfluss von Störgrößen eliminiert werden.For a very accurate statement about the degree of NH 3 -loading, the high-frequency measurement offers the possibility of viewing several frequency ranges. This exploits the fact that the changes in the signal due to the NH 3 charge have a different effect compared to the transverse influences in different frequency ranges. Thus, by correlating the effects in different frequency ranges, the influence of disturbances can be eliminated.

Frequenzbereiche in diesem Zusammenhang sind Bereiche um eine Resonanzfrequenz bzw. um die gewünschte Messfrequenz. Sie schließen mindestens einen Peak (mit Peak ist hier ein Minimum oder Maximum im Betrag des Reflexions- oder des Transmissionsparameters gemeint) für den gesamten Umfang der Messung ein, d. h. auch wenn Verschiebungen dieser Resonanzfrequenz auftreten, muss immer noch mindestens ein vollständiger Peak innerhalb des gewählten Frequenzbereichs liegen.Frequency ranges in this context are ranges around a resonance frequency or around the desired measurement frequency. They include at least one peak (peak here being meant a minimum or maximum in the amount of the reflection or transmission parameter) for the entire circumference of the measurement, i. H. even if shifts in this resonance frequency occur, at least one complete peak must still be within the selected frequency range.

Der Fachmann erwartet, dass die Auswirkungen einer Änderung der elektrischen Leitfähigkeit oder der Permittivität auf die Reflexions- oder Transmissionsparameter unabhängig von der physikalischen Ursache der Änderung sind. Dennoch beobachtet man experimentell, dass zwei verschiedene Einflusseffekte bei einer Frequenz zu denselben Änderungen der Reflexions- oder Transmissionsparameter und zugleich bei einer anderen Frequenz zu voneinander verschiedenen Änderungen führen können. Beispielsweise ändern sich die Reflexions- oder Transmissionsparameter während der Messung von NH3 und Quereinflüssen in unterschiedlicher Weise, auch wenn sich die elektrischen Eigenschaften des Speichermaterials gleich verändern.One skilled in the art would expect the effects of a change in electrical conductivity or permittivity on the reflection or transmission parameters to be independent of the physical cause of the change. However, it has been observed experimentally that two different effects of one frequency at one frequency can lead to the same changes in the reflection or transmission parameters and at the same time at a different frequency to mutually different changes. For example, the reflection or transmission parameters change in a different manner during the measurement of NH 3 and cross influences, even if the electrical properties of the memory material change the same.

Durch diesen bislang unverstandenen Effekt ist dieses Verfahren auf die Ermittlung der Ammoniak-Beladung des SCR-Katalysators mit nur einer Antenne anwendbar. Die Betrachtung mehrerer Frequenzbereiche ermöglicht die Unterscheidung von NH3-Effekt von sonstigen Quereinflüssen. Damit lässt sich die Störgröße ermitteln und das Messsignal rechnerisch korrigieren.Due to this hitherto incomprehensible effect, this method is applicable to the determination of the ammonia loading of the SCR catalyst with only one antenna. The consideration of several frequency ranges enables the distinction of NH 3 effect from other cross influences. This allows the disturbance to be determined and the measured signal to be corrected mathematically.

Ausführungsbeispieleembodiments

Die Möglichkeit der Differenzierung von unterschiedlichen Einflüssen ist in der Zeichnung dargestellt und in der nachfolgenden Beschreibung näher erläutert.The possibility of differentiation of different influences is shown in the drawing and explained in more detail in the following description.

1 zeigt schematisch einen SCR-Katalysator (1), der in ein metallisches Gehäuse (2) eingebracht ist. Über eine Antenne (3), die auch als Feldsonde bezeichnet werden kann und die hier als kapazitiver Stiftkoppler ausgeführt ist, wird ein Hochfrequenzsignal eingespeist und das reflektierte Signal gemessen. Die Einspeisebeschaltung, die Verkabelung und die Reflektionsmessung sind bekannt und daher hier nicht weiter ausgeführt. Die Anordnung lässt sich erfindungsgemäß auch mit zwei Antennen, z. B. angeordnet vor und nach Katalysator, betreiben. Dann wird die Transmission gemessen. 1 schematically shows an SCR catalyst ( 1 ) placed in a metallic housing ( 2 ) is introduced. Via an antenna ( 3 ), which can also be referred to as a field probe and which is embodied here as a capacitive pin coupler, a high-frequency signal is fed in and the reflected signal is measured. The feed-in circuit, the wiring and the reflection measurement are known and therefore not further elaborated here. The arrangement can be inventively with two antennas, z. B. arranged before and after the catalyst, operate. Then the transmission is measured.

Für die Messung werden mehrere Signalmerkmale bzw. mehrere Frequenzbereiche verwendet. Dies ermöglicht die Unterscheidung zu Quereinflüssen und somit die genauere Beladungserkennung des SCR-Speicherkatalysators.Several signal characteristics or several frequency ranges are used for the measurement. This makes it possible to distinguish between lateral influences and thus the more accurate load recognition of the SCR storage catalytic converter.

2 zeigt Messungen im Frequenzbereich von 1 bis 3,5 GHz an einem SCR-Katalysator im Grundgas (5% H2O in N2) bei ca. 300°C. Gemessen wird der Reflexionsparameter S11. Dargestellt ist der Betrag dieses Parameters |S11| in dB (|S11|/dB = 20·log|S11|) über der Frequenz. Es sind unterschiedliche Resonanzpeaks zu erkennen. Es werden 500 ppm NH3 zudosiert, bis durch die Gasanalyse nach Katalysator (FTIR) das Ende des Speichervorgangs bestätigt wird und 500 ppm NH3 nach Katalysator gemessen werden. Die durchgezogene Linie im Diagramm zeigt das Spektrum nach der vollständigen Beladung des Katalysators. 2 shows measurements in the frequency range of 1 to 3.5 GHz on an SCR catalyst in the base gas (5% H 2 O in N 2 ) at about 300 ° C. The reflection parameter S 11 is measured. Shown is the amount of this parameter | S 11 | in dB (| S 11 | / dB = 20 · log | S 11 |) over the frequency. There are different resonance peaks. 500 ppm NH 3 are metered in until the end of the storage process is confirmed by the gas analysis after catalyst (FTIR) and 500 ppm of NH 3 are measured after the catalyst. The solid line in the diagram shows the spectrum after the complete loading of the catalyst.

Mit der Beladung mit Ammoniak ändert sich dieses Spektrum deutlich, so dass die Beladung direkt gemessen werden kann. With the loading of ammonia, this spectrum changes significantly, so that the load can be measured directly.

3 zeigt beispielhaft die Kennlinie der Resonanzfrequenz des Messsystems bei ca. 2,9 GHz mit steigender Ammoniakbeladung. Es ist ein monotoner, sogar nahezu linearer Zusammenhang zwischen der NH3-Beladung mNH3 und dem Messsignal fres zu erkennen. Die Beladung wird dabei aus der Gasanalyse nach Katalysator und einer Bilanzierung unter Kenntnis des Gasflusses und unter Berücksichtigung des Blindumsatzes einer Leermessung ermittelt. 3 shows an example of the characteristic of the resonance frequency of the measuring system at about 2.9 GHz with increasing ammonia loading. It is a monotonic, even almost linear relationship between the NH 3 load m NH3 and the measurement signal f res to detect. The load is determined from the gas analysis after catalyst and a balance with knowledge of the gas flow and taking into account the reactive conversion of a blank measurement.

Betrachtet man zusätzlich die Wasserquerempfindlichkeit des Messsystems in der Tabelle, so erkennt man, dass in bestimmten Frequenzbereichen (z. B. ca. 2,1 GHz) die Empfindlichkeit auf Wasser größer ist als auf NH3. In der nachfolgenden Tabelle sind die relativen Änderungen der Resonanzfrequenzen auf NH3 (xNH3) und H2O (xH2O) dargestellt und ins Verhältnis gesetzt. Das Verhältnis xNH3/xH2O gibt an, um wie viel höher die Empfindlichkeit des Messsystems bei der entsprechenden Frequenz auf den Effekt der Ammoniak-Einspeicherung im Vergleich zum Wassereffekt ist. Liegt dieser Wert unter 1, ist der Wassereffekt stärker als die Änderung durch die NH3-Speicherung. Durch die Betrachtung zweier Frequenzbereiche wird hier die Unterscheidung zwischen NH3- und H2O-Effekt möglich. Eignen würden sich in diesem Fall die Frequenzen von ca. 1623 MHz und 2100 MHz, da sich hier die Messeffekte auf H2O und NH3 deutlich unterscheiden. Tabelle: Signaländerungen des Messsystems auf NH3 und H2O in unterschiedlichen Frequenzbereichen fres/MHz 1307 1623 2100 2380 2920 NH3:xNH3/ppm = Δfres/fres 7367 4658 1058 3190 2352 H2O:xH2O/ppm = Δfres/fres 1324 451 1772 428 398 xNH3/xH2O 5.56 10.32 0.6 7.46 5.9 If one additionally considers the water interference sensitivity of the measuring system in the table, one recognizes that in certain frequency ranges (eg approx. 2.1 GHz) the sensitivity to water is greater than to NH 3 . In the following table, the relative changes of the resonance frequencies to NH 3 (x NH3 ) and H 2 O (x H2O ) are shown and related. The ratio x NH3 / x H2O indicates how much higher the sensitivity of the measuring system at the corresponding frequency is to the ammonia storage effect compared to the water effect. If this value is less than 1, the water effect is stronger than the change due to NH 3 storage. By considering two frequency ranges, the distinction between NH 3 and H 2 O effect becomes possible. In this case, the frequencies of approx. 1623 MHz and 2100 MHz would be appropriate, since here the measurement effects on H 2 O and NH 3 differ significantly. Table: Signal changes of the measuring system to NH 3 and H 2 O in different frequency ranges f res / MHz 1307 1623 2100 2380 2920 NH 3: x NH3 / ppm = .DELTA.f res / f res 7367 4658 1058 3190 2352 H 2 O: x H2O / ppm = Δf res / f res 1324 451 1772 428 398 x NH3 / x H2O 5:56 10:32 0.6 7:46 5.9

Eine Veränderung der Resonanzfrequenzen ist auch mit variierender Temperatur zu erwarten. Hier kann ebenso eine Betrachtung mehrerer Frequenzbereiche dazu beitragen, den Temperatureffekt aus dem Messsignal zu eliminieren. Alternativ kann durch eine zusätzliche Temperaturmessung die aktuelle Temperatur ermittelt und das Messsignal korrigiert werden. In diesem Fall kann auch der Messfrequenzbereich nachgeführt werden, um den idealen Messbereich für die aktuelle Temperatur zu erhalten.A change of the resonance frequencies is to be expected also with varying temperature. Here as well a consideration of several frequency ranges can help to eliminate the temperature effect from the measurement signal. Alternatively, the current temperature can be determined by an additional temperature measurement and the measurement signal corrected. In this case, the measuring frequency range can also be tracked to obtain the ideal measuring range for the current temperature.

Neben der kontinuierlichen Messung im Frequenzbereich ist auch die Messung im Zeitbereich möglich. Dies kann z. B. durch eine Impulsanregung geschehen. Dabei wird ein Signal in Form eines kurzen Impulses aufgegeben und die Laufzeit ausgewertet. Auch ist hier die Auswertung von Laufzeitunterschieden mit mehreren Antennen möglich. So kann an einer Antenne der Impuls aufgegeben und die frequenzabhängige Laufzeit bis zum Empfang an der zweiten Antenne gemessen werden.In addition to the continuous measurement in the frequency domain, the measurement in the time domain is possible. This can be z. B. done by a pulse excitation. A signal in the form of a short pulse is given up and the runtime is evaluated. Also here is the evaluation of runtime differences with multiple antennas possible. Thus, the pulse can be applied to an antenna and the frequency-dependent transit time can be measured until it is received at the second antenna.

Die Art der Ankopplung ist nicht auf die bereits gezeigte kapazitive Stiftkopplung beschränkt. Es kann auch induktiv angekoppelt werden (Schleifenantenne). Außerdem kann auch seitlich am Abgasnachbehandlungssystem, d. h. nicht direkt im Abgasstrom, ein weiteres Rohr angesetzt werden, um dort die Antenne einzubauen. Dies ist in 4 skizziert. Auch hier ist der SCR-Katalysator (1) in dem metallischen Gehäuse (2) mit der entsprechenden Antenne (3) gezeigt. Dies kann insbesondere dann sinnvoll sein, wenn die Funktion der Antennen im Abgasstrom z. B. durch Anlagerung von Ruß nicht dauerhaft gewährleistet ist.The type of coupling is not limited to the already shown capacitive pin coupling. It can also be inductively coupled (loop antenna). In addition, another side of the exhaust aftertreatment system, ie not directly in the exhaust stream, another pipe can be used to install the antenna there. This is in four outlined. Again, the SCR catalyst ( 1 ) in the metallic housing ( 2 ) with the corresponding antenna ( 3 ). This may be particularly useful if the function of the antennas in the exhaust stream z. B. is not permanently guaranteed by the addition of soot.

ZITATE ENTHALTEN IN DER BESCHREIBUNG QUOTES INCLUDE IN THE DESCRIPTION

Diese Liste der vom Anmelder aufgeführten Dokumente wurde automatisiert erzeugt und ist ausschließlich zur besseren Information des Lesers aufgenommen. Die Liste ist nicht Bestandteil der deutschen Patent- bzw. Gebrauchsmusteranmeldung. Das DPMA übernimmt keinerlei Haftung für etwaige Fehler oder Auslassungen.This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Zitierte PatentliteraturCited patent literature

  • DE 10358495 A1 [0003, 0009] DE 10358495 A1 [0003, 0009]
  • DE 102008012050 A1 [0003, 0009] DE 102008012050 A1 [0003, 0009]
  • US 4477771 [0003, 0009] US 4477771 [0003, 0009]
  • US 5497099 [0003] US 5497099 [0003]

Zitierte Nicht-PatentliteraturCited non-patent literature

  • D. Y. Wang, S. Yao, M. Shost, J. Yoo, D. Cabush, D. Racine, R. Cloudt, F. Willems: Ammonia sensor for Closed-Loop SCR Control. SAE paper 2008-01-0919 (2008) [0001] DY Wang, S. Yao, M. Shost, J. Yoo, D. Cabush, D. Racine, R. Cloudt, F. Willems: Ammonia sensor for closed-loop SCR control. SAE paper 2008-01-0919 (2008) [0001]

Claims (5)

Verfahren zur Erfassung des aktuellen Zustands eines auf der SCR-Technologie basierenden Abgasnachbehandlungssystems in Kraftfahrzeugen, Lastkraftwagen, stationären Verbrennungsanlagen oder vergleichbaren Einrichtungen, das die Ausbreitung elektromagnetischer Wellen innerhalb eines Hohlleiters nutzt, wobei sich die elektromagnetische Welle in einem metallischen Gehäuse ausbreitet und durch den Zustand der eingebauten Katalysatorsysteme gestört wird, dadurch gekennzeichnet, dass Messungen in mehreren Frequenzbereichen eingesetzt werden und in diesen Bereichen Messgrößen bestimmt werden, beispielsweise der Reflexionsfaktorbetrag bei einer Resonanzspitze oder die Verschiebung von Resonanzfrequenzen, um mit einer Messeinrichtung Rückschlüsse auf den Speicherzustand unter Berücksichtigung von Quereinflüssen zu ermöglichen.A method for detecting the current state of an SCR technology-based exhaust aftertreatment system in automobiles, trucks, stationary incinerators or similar devices that utilizes the propagation of electromagnetic waves within a waveguide, wherein the electromagnetic wave propagates in a metallic housing and by the state of the is disturbed built-in catalyst systems, characterized in that measurements are used in several frequency ranges and in these areas measured variables are determined, for example, the reflection factor at a resonance peak or the shift of resonance frequencies to allow conclusions with a measuring device on the memory state, taking into account cross influences. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass mit veränderter Temperatur auch der Messfrequenzbereich verändert wird um den größtmöglichen Messeffekt zu erzielen.A method according to claim 1, characterized in that with changed temperature and the measuring frequency range is changed in order to achieve the largest possible measuring effect. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass eine Signalauswertung im Zeitbereich vorgenommen wird.A method according to claim 1, characterized in that a signal evaluation in the time domain is performed. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass die Einkopplung elektromagnetischer Wellen kapazitiv oder auch induktiv erfolgen kann.A method according to claim 1, characterized in that the coupling of electromagnetic waves can be capacitive or inductive. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass die Signaleinkopplung bzw. -auskopplung durch ein zusätzliches Anbauteil am Systemgehäuse erfolgt.A method according to claim 1, characterized in that the signal coupling or decoupling takes place by an additional attachment to the system housing.
DE102010034983A 2010-08-20 2010-08-20 Method for detecting current state of exhaust after-treatment system in e.g. motor car, involves determining measured variables in different frequency ranges to allow measuring device to provide conclusions about memory state Ceased DE102010034983A1 (en)

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Cited By (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015090342A1 (en) * 2013-12-19 2015-06-25 Volvo Truck Corporation System and method for determining a parameter indicative of an amount of a reducing agent
WO2015173150A1 (en) * 2014-05-16 2015-11-19 Umicore Ag & Co. Kg Method for detecting the degree of aging of catalytic converters
DE102015001229A1 (en) 2015-02-03 2016-08-04 Markus Dietrich Device for coupling and / or decoupling microwaves into the exhaust gas line of an internal combustion engine
DE102015001228A1 (en) 2015-02-03 2016-08-04 Markus Dietrich Antenna module with two combined antennas for a method for state detection of exhaust aftertreatment components using microwaves
DE102015001231A1 (en) 2015-02-03 2016-08-04 Markus Dietrich A method for simultaneously monitoring the various functions of a multi-component exhaust aftertreatment system with a single microwave based measurement system
DE102015001230A1 (en) 2015-02-03 2016-08-04 Markus Dietrich Thermocouple thermocouple antennas for a method of detecting the state of a catalyst with microwaves
EP3073082A1 (en) * 2015-03-26 2016-09-28 General Electric Company Systems and methods for monitoing the health of a selective catalytic reduction catalyst
DE102015006232A1 (en) 2015-05-18 2016-11-24 Markus Dietrich Method for loading and / or condition detection of exhaust aftertreatment components using microwaves
DE102016206462A1 (en) * 2016-04-18 2017-03-09 Continental Automotive Gmbh Method for operating an SCR catalytic converter of an internal combustion engine
DE102015116659A1 (en) * 2015-10-01 2017-04-20 Umicore Ag & Co. Kg Method and device for determining an indication of a storage capacity of a reagent in an exhaust aftertreatment device
WO2018050354A1 (en) * 2016-09-19 2018-03-22 Continental Automotive Gmbh Method for operating a catalyst device in a motor vehicle
WO2018065141A1 (en) * 2016-10-07 2018-04-12 Continental Automotive Gmbh On-board diagnostics for an exhaust gas catalytic converter and detection of aging
DE102016219640A1 (en) * 2016-10-10 2018-04-12 Continental Automotive Gmbh Catalyst aging detection with minimal ammonia slip
WO2018068994A1 (en) * 2016-10-10 2018-04-19 Continental Automotive Gmbh Self-diagnosis of a catalytic converter by s-parameter measurement
DE102017200542A1 (en) 2017-01-13 2018-07-19 Robert Bosch Gmbh Method for determining a nitrogen oxide mass flow
DE102017205322A1 (en) 2017-03-29 2018-10-04 Robert Bosch Gmbh Method for detecting damage to an SCR catalyst
DE102017205319A1 (en) 2017-03-29 2018-10-04 Robert Bosch Gmbh Method for detecting damage to an SCR catalyst
DE102017206906A1 (en) 2017-04-25 2018-10-25 Robert Bosch Gmbh Method for determining an accuracy of a reducing agent solution dosage and / or a concentration of the metered reducing agent solution
WO2018219734A1 (en) 2017-05-30 2018-12-06 Continental Automotive Gmbh Exhaust gas line arrangement for an internal combustion engine
DE102017209044A1 (en) * 2017-05-30 2018-12-06 Continental Automotive Gmbh Method and arrangement for resonant frequency determination of an exhaust aftertreatment system
WO2018219736A1 (en) 2017-05-30 2018-12-06 Continental Automotive Gmbh Exhaust gas pipe assembly for an internal combustion engine
DE102018110214A1 (en) 2018-04-27 2019-04-04 Iav Gmbh Ingenieurgesellschaft Auto Und Verkehr Method for detecting the condition of a high-frequency antenna for an SCR catalytic converter
CN109891065A (en) * 2016-10-10 2019-06-14 世倍特集团有限责任公司 Catalyst converter aging is identified in the case where no additional system unit
EP3527796A1 (en) * 2018-02-15 2019-08-21 Toyota Jidosha Kabushiki Kaisha Abnormality diagnosis apparatus and vehicle
EP3540187A1 (en) * 2018-03-12 2019-09-18 Toyota Jidosha Kabushiki Kaisha Abnormality diagnosis apparatus
WO2019229398A1 (en) * 2018-06-01 2019-12-05 Continental Automotive France Predictive machine learning for predicting a resonance frequency of a catalyst for the selective catalytic reduction of nitrogen oxides
DE102020002623A1 (en) 2020-04-30 2021-11-04 Gunter Hagen Method for simultaneous temperature and condition monitoring of an exhaust gas aftertreatment element
DE102016118368B4 (en) 2015-10-01 2022-08-11 Ford Global Technologies, Llc High frequency air-fuel ratio control

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4477771A (en) 1982-06-21 1984-10-16 General Motors Corporation Microwave detection of soot content in a particulate trap
US5497099A (en) 1991-09-06 1996-03-05 Engine Control Systems Ltd. Antenna system for soot detecting
DE10358495A1 (en) 2003-12-13 2005-07-14 Daimlerchrysler Ag Catalyst status detection method e.g. for NOx storage catalyst, involves having interior of housing of catalyst having gas in it and having quality measure of cavity for gas with resonant frequency decreased as measure of increase of NOx
DE102008012050A1 (en) 2008-02-29 2009-09-03 Fischerauer, Gerhard, Prof. Dr.-Ing. Exhaust after-treatment system operating method for motor vehicle, involves regulating condition of catalyzer as continues input variable of engine control for regulation of exhaust after-treatment system

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4477771A (en) 1982-06-21 1984-10-16 General Motors Corporation Microwave detection of soot content in a particulate trap
US5497099A (en) 1991-09-06 1996-03-05 Engine Control Systems Ltd. Antenna system for soot detecting
DE10358495A1 (en) 2003-12-13 2005-07-14 Daimlerchrysler Ag Catalyst status detection method e.g. for NOx storage catalyst, involves having interior of housing of catalyst having gas in it and having quality measure of cavity for gas with resonant frequency decreased as measure of increase of NOx
DE102008012050A1 (en) 2008-02-29 2009-09-03 Fischerauer, Gerhard, Prof. Dr.-Ing. Exhaust after-treatment system operating method for motor vehicle, involves regulating condition of catalyzer as continues input variable of engine control for regulation of exhaust after-treatment system

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
D. Y. Wang, S. Yao, M. Shost, J. Yoo, D. Cabush, D. Racine, R. Cloudt, F. Willems: Ammonia sensor for Closed-Loop SCR Control. SAE paper 2008-01-0919 (2008)

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CN105829672A (en) * 2013-12-19 2016-08-03 沃尔沃卡车集团 System and method for determining a parameter indicative of an amount of a reducing agent
US10060320B2 (en) 2013-12-19 2018-08-28 Volvo Truck Corporation System and method for determining a parameter indicative of an amount of a reducing agent
EP3553289A1 (en) * 2013-12-19 2019-10-16 Volvo Truck Corporation System and method for determining a parameter indicative of an amount of a reducing agent
WO2015090342A1 (en) * 2013-12-19 2015-06-25 Volvo Truck Corporation System and method for determining a parameter indicative of an amount of a reducing agent
CN105829672B (en) * 2013-12-19 2020-02-07 沃尔沃卡车集团 System and method for determining a parameter indicative of the amount of reducing agent
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WO2015173150A1 (en) * 2014-05-16 2015-11-19 Umicore Ag & Co. Kg Method for detecting the degree of aging of catalytic converters
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