DE102017211531A1 - Internal combustion engine and method for the regeneration of a particulate filter in the exhaust passage of an internal combustion engine - Google Patents

Abstract

The invention relates to an internal combustion engine, in whose exhaust system a three-way catalyst and a particle filter are arranged. The exhaust system is connected via a high-pressure exhaust gas recirculation with the intake of the engine. If a critical load condition of the particulate filter is detected with a high component temperature of the particulate filter, a coasting operation of the internal combustion engine can lead to an uncontrolled Rußabbrand on the particulate filter. In order to avoid this, an exhaust valve is closed for component protection of the particulate filter and an exhaust gas recirculation valve is opened, so that the exhaust gas is returned to the intake and the engine delivers a substantially stoichiometric exhaust gas, even during overrun, so that uncontrolled Rußabbrand on the particulate filter is avoided

Description

The invention relates to an internal combustion engine and to a method for the regeneration of a particulate filter arranged in an exhaust aftertreatment system of an internal combustion engine.

The continuous tightening of the exhaust emission legislation places high demands on the vehicle manufacturers, which are solved by appropriate measures for the reduction of the engine raw emissions and by a corresponding exhaust aftertreatment. With the introduction of the legislative level EU6, a limit value for gasoline engines is prescribed for a number of particles, which in many cases necessitates the use of an Otto particle filter. When driving, such a gasoline particulate filter is loaded with soot. So that the exhaust gas backpressure does not increase too much, this Otto particle filter must be regenerated continuously or periodically. The increase in the exhaust back pressure can lead to an increase in consumption of the internal combustion engine, loss of power and impairment of smoothness to misfires. In order to carry out a thermal oxidation of the soot retained in the Otto particle filter with oxygen, a sufficiently high temperature level in conjunction with simultaneously existing oxygen in the exhaust system of the gasoline engine is necessary. Since modern gasoline engines are normally operated without oxygen surplus with a stoichiometric combustion air ratio (λ = 1), additional measures are required. These come as measures, for example, a temperature increase by a Zündwinkelverstellung, a temporary lean adjustment of the gasoline engine, the injection of secondary air into the exhaust system or a combination of these measures in question. An ignition angle adjustment in the direction of late in combination with a lean adjustment of the gasoline engine is preferably used so far, since this method requires no additional components and can deliver a sufficient amount of oxygen in most operating points of the gasoline engine.

In the case of an Otto-particle filter, however, loading conditions also occur in which an uncontrolled flow through the Otto-particle filter with oxygen is undesirable. If the loading level of the Otto particle filter reaches a critical level, for example, a coasting phase of the internal combustion engine, together with a high temperature of the Otto particle filter, can lead to an uncontrolled Rußabbrand on the Ottopartikelfilter. The exothermic oxidation of the soot particles can cause such high temperatures on the component surface of the Otto particle filter that thermal damage to the Otto particle filter can occur. It may therefore be necessary to reduce or completely eliminate the oxygen input into the Otto particle filter in certain operating situations.

From the DE 10 2010 039 013 A1 For example, a method and a device for the regeneration of a particulate filter in an exhaust gas passage of a gasoline engine are known, wherein a three-way catalytic converter is arranged in the exhaust gas passage downstream of the particulate filter. It is provided that during the regeneration of the particulate filter by means of a lambda control with a lambda probe downstream of the three-way catalyst, a stoichiometric exhaust gas is adjusted. For this purpose, upon detection of an excess of oxygen downstream of the three-way catalytic converter, the combustion air ratio is adjusted in the direction of a rich direction and, in particular, in a coasting operation of the internal combustion engine, an unfired operation of the internal combustion engine is suppressed.

From the DE 10 2010 046 896 A1 For example, a system and method for regenerating a catalyst-accompanied particulate filter in an exhaust passage of a gasoline engine is known, wherein the exhaust passage downstream of a three-way catalyst and a particulate filter via a low-pressure exhaust gas recirculation is connected to the intake passage upstream of the compressor of a turbocharger. In this case, the three-way catalyst in the exhaust passage downstream of the particulate filter is arranged to allow during the regeneration of the particulate filter efficient exhaust gas purification by the three-way catalyst.

The DE 10 2012 021 882 A1 discloses an internal combustion engine and a method for operating an internal combustion engine whose exhaust gas flows through at least one particle filter. In this case, in a coasting operation of the internal combustion engine, when the particulate filter has reached a certain loading and / or temperature level, the fuel cut-off suppressed and further injected fuel into the combustion chambers of the internal combustion engine to prevent uncontrolled Rußabbrand on the particulate filter.

In addition, from the DE 10 2014 118 813 A1 an internal combustion engine with an exhaust gas recirculation system is known, which has a high-pressure exhaust gas recirculation and a plurality of low-pressure exhaust gas recirculation, wherein the low-pressure exhaust gas recirculation is made in several stages.

The object of the invention is to prevent an uncontrolled Rußabbrand on the particulate filter during a coasting operation of the internal combustion engine, the disadvantages of a fired overrun operation, in particular the increased fuel consumption and the lower engine braking power in overrun, are overcome.

According to the invention this object is achieved by an internal combustion engine with an air supply system and an exhaust system, wherein the air supply system comprises a throttle valve with which an air supply to the combustion chambers of the internal combustion engine can be controlled and having a compressor of an exhaust gas turbocharger, wherein the exhaust system comprises a turbine of the exhaust gas turbocharger and at least a three-way catalyst and a particulate filter, which are arranged downstream of the turbine of the exhaust gas turbocharger, and with a high-pressure exhaust gas recirculation line, which connects the exhaust system upstream of the turbine with the air supply system downstream of the compressor, and wherein downstream in the exhaust system at least one of Exhaust after-treatment components an exhaust valve is arranged. Through the exhaust valve, the exhaust gas of the internal combustion engine can be supplied to the intake passage of the internal combustion engine, whereby a circulation of the exhaust gas is possible. This can be prevented in a coasting operation of the internal combustion engine that oxygen-rich fresh air is supplied to the particulate filter in the exhaust system. As a result, an uncontrolled Rußabbrand be prevented on the particulate filter, whereby the risk of thermal damage to the particulate filter is significantly reduced. By means of a high-pressure exhaust gas recirculation, in which the exhaust gas is supplied to the intake tract downstream of the compressor, a sufficient scavenging gradient is present even at low exhaust gas volumes to supply the exhaust gas via the exhaust gas recirculation line to the air supply system. By closing the exhaust valve, this purging gradient can be increased, since the pressure in the exhaust passage upstream of the exhaust valve then increases.

The features listed in the dependent claims advantageous improvements and developments of the specified in the independent claim exhaust aftertreatment system of an internal combustion engine are possible.

In a preferred embodiment of the invention it is provided that the throttle valve is arranged downstream of the compressor of the exhaust gas turbocharger and upstream of the discharge point of the high-pressure exhaust gas recirculation. By closing the throttle valve, the afterflow of fresh air can thus be substantially avoided, so that in exhaustive operation, the exhaust gas circulates through the high-pressure exhaust gas recirculation and no oxygen passes to the particle filter for oxidation of the soot. As a result, the exhaust gas circulation can be promoted by the high-pressure exhaust gas recirculation.

It is particularly preferred if an exhaust gas cooler is arranged in the exhaust gas recirculation line. By means of an exhaust gas cooler, the combustion temperature can be lowered during normal operation of the engine when the exhaust gas recirculation valve is open, as a result of which the raw emissions of the internal combustion engine can be positively influenced.

In a further preferred embodiment of the invention, it is provided that both the three-way catalytic converter and the particle filter are arranged in a position close to the engine in the exhaust system and the exhaust valve is located downstream of both exhaust aftertreatment components. By a close-coupled arrangement of both the particulate filter and the three-way catalyst is a particularly rapid heating of the two exhaust aftertreatment components after a cold start of the engine possible. Under a close-coupled arrangement in this context is an arrangement with a distance of less than 80 cm, preferably less than 50 cm exhaust run length, to be understood from an outlet of the internal combustion engine. In addition, during a circulation of the exhaust gas through the high-pressure exhaust gas recirculation line with the exhaust valve closed, there is no risk that the three-way catalyst cools below its light-off temperature, so that even after completion of the component protection measure and after a subsequent opening of the exhaust flap is ensured in that an efficient conversion of the exhaust gas components through the three-way catalyst is possible.

In a preferred embodiment of the invention, it is provided that the particle filter is designed as a particle filter with a three-way catalytically active coating as a so-called four-way catalyst. Through a four-way catalyst, the exhaust gas can be freed from both particles and harmful gaseous exhaust gas components. This can optionally be dispensed with an additional catalyst.

Alternatively, it is advantageously provided that a first exhaust aftertreatment component in the exhaust system upstream of the exhaust valve and a second exhaust aftertreatment component are arranged downstream of the exhaust valve. This results in further degrees of freedom in the arrangement of the exhaust aftertreatment components, so in particular a close-coupled particle filter can be combined with a three-way catalytically active coating with a three-way catalyst in a bottom layer of the motor vehicle. Thus, additional catalyst volume is provided, so that even with aging of the catalyst and a concomitant reduction in the conversion efficiency, an efficient exhaust aftertreatment of the exhaust gas of the internal combustion engine is still possible. In this case, the particulate filter of the circulating exhaust gas flows through and maintained at a temperature to allow subsequent to the overrun at a fired operation of the internal combustion engine regeneration of the particulate filter and to prevent strong cooling below the regeneration temperature.

Alternatively, it is advantageously provided that the first exhaust aftertreatment component is a three-way catalyst and the exhaust valve is arranged downstream of the three-way catalyst and downstream of the particulate filter. Through an exhaust valve downstream of the three-way catalyst, the three-way catalyst can be kept at temperature to allow efficient conversion of the pollutants in a subsequent normal operation. Due to the decoupling of the fresh air supply, the risk of uncontrolled Rußabbrandes on the particulate filter can be drastically reduced, since it is only flowed through by a leakage current when the exhaust valve is closed. In addition, this low leakage flow then also has a substantially stoichiometric exhaust gas, so that there is no significant soot turnover on the particle filter.

In a preferred embodiment of the invention, provision is made for a control valve, in particular an exhaust gas recirculation valve, to be arranged in the high-pressure exhaust gas recirculation line for controlling the amount of exhaust gas recirculated via the high-pressure exhaust gas recirculation line.

• - Betreiben des Verbrennungsmotors in einem Normalbetrieb, wobei der Partikelfilter mit Rußpartikeln aus dem Abgas des Verbrennungsmotors beladen wird,
• - Erkennen eines Beladungszustands sowie einer Temperatur des Partikelfilters,
• - Öffnen des Abgasrückführungsventils,
• - Schließen der Abgasklappe, wenn in einem kritischen Beladungszustand und/oder bei einer kritischen Bauteiltemperatur des Partikelfilters ein Schubbetrieb des Verbrennungsmotors eingeleitet wird.

According to the invention, a method for regeneration and thermal management of the particulate filter in an exhaust system of an internal combustion engine according to the invention is proposed, which comprises the following steps:

• Operating the internal combustion engine in a normal operation, wherein the particle filter is loaded with soot particles from the exhaust gas of the internal combustion engine,
• Detecting a loading state and a temperature of the particulate filter,
• Opening the exhaust gas recirculation valve,
• - Close the exhaust valve, when in a critical load condition and / or at a critical component temperature of the particulate filter, a coasting operation of the internal combustion engine is initiated.

An inventive method an effective component protection of the particulate filter in a coasting operation of the internal combustion engine is possible, the braking torque of the engine (unlike a fired overrun operation) is not reduced and the full engine braking power is available. In addition, there is an additional fuel economy from the fact that the oxygen storage of the three-way catalyst during the coasting phase is not or at least not filled to the extent with oxygen and therefore need not be eliminated following the thrust phase by a substoichiometric operation of the engine ,

In an advantageous improvement of the method, it is provided that the internal combustion engine is operated with a stoichiometric combustion air ratio (λ = 1) until the exhaust gas flap is completely closed. Stoichiometric engine operation until complete closure of the exhaust gas flap can ensure that no oxygen-rich exhaust gas is introduced into the particulate filter even in the first overrun phase and that uncontrolled oxidation of the soot retained in the particulate filter occurs.

In a preferred embodiment of the method, it is provided that in a coasting phase of the internal combustion engine with the exhaust valve closed, fuel is introduced into the combustion chambers of the internal combustion engine. In order to ensure even during a prolonged coasting phase that there is no increase in the oxygen content in the exhaust gas circulating through the exhaust gas recirculation line, it is provided that, in addition, small quantities of fuel are introduced into the combustion chambers of the internal combustion engine. This is preferably done by a fuel injection into the combustion chambers of the internal combustion engine, but can alternatively also be effected by an injection into the air supply system of the internal combustion engine.

The various embodiments of the invention mentioned in this application are, unless otherwise stated in the individual case, advantageously combinable with each other.

• 1 ein erstes Ausführungsbeispiel eines erfindungsgemäßen Verbrennungsmotors;
• 2 ein weiteres Ausführungsbeispiel eines erfindungsgemäßen Verbrennungsmotors, wobei ein Normalbetrieb des Verbrennungsmotors dargestellt ist;
• 3 das Ausführungsbeispiel gemäß 2, wobei ein erfindungsgemäßes Verfahren zum Bauteilschutz des Partikelfilters dargestellt ist;
• 4 ein weiteres Ausführungsbeispiel eines erfindungsgemäßen Verbrennungsmotors;
• 5 ein weiteres Ausführungsbeispiel eines erfindungsgemäßen Verbrennungsmotors, wobei die Abgasklappe stromaufwärts des Drei-Wege-Katalysators angeordnet ist;
• 6 ein weiteres Ausführungsbeispiel eines erfindungsgemäßen Verbrennungsmotors, wobei die Abgasklappe stromabwärts des Drei-Wege-Katalysators und stromaufwärts des Partikelfilters angeordnet ist; und
• 7 ein Verlauf der Fahrzeuggeschwindigkeit eines Kraftfahrzeuges bei einem Schubbetrieb mit Schubabschaltung und bei einem gefeuerten Schubbetrieb.

The invention will be explained below in embodiments with reference to the accompanying drawings. The same components or components with the same function in the drawings are each identified by the same reference numerals. Show it:

• 1 a first embodiment of an internal combustion engine according to the invention;
• 2 a further embodiment of an internal combustion engine according to the invention, wherein a normal operation of the internal combustion engine is shown;
• 3 the embodiment according to 2 wherein an inventive method for component protection of the particulate filter is shown;
• 4 a further embodiment of an internal combustion engine according to the invention;
• 5 a further embodiment of an internal combustion engine according to the invention, wherein the exhaust valve is arranged upstream of the three-way catalyst;
• 6 a further embodiment of an internal combustion engine according to the invention, wherein the exhaust valve is disposed downstream of the three-way catalyst and upstream of the particulate filter; and
• 7 a course of the vehicle speed of a motor vehicle in a coasting operation with fuel cut and a fired overrun operation.

1 shows an internal combustion engine 10 for a motor vehicle, which as one with spark plugs 18 externally ignited internal combustion engine 10 executed according to the Otto principle. The internal combustion engine 10 is with his outlet 16 with an exhaust system 40 connected. The outlet 16 includes an exhaust manifold, which the exhaust gases of the different combustion chambers 12 of the internal combustion engine 10 an exhaust duct 52 the exhaust system 40 supplies. The internal combustion engine 10 is with an inlet 14 with an air supply system 20 connected. The air supply system 20 points in the direction of flow of fresh air through the air supply system 20 a compressor 26 an exhaust gas turbocharger 38 on, with which the sucked air is compressed and the combustion chambers 12 of the internal combustion engine 10 is supplied. Downstream of the compressor 26 is in the air supply system 20 a throttle 22 arranged, with which the air supply to the combustion chambers 12 of the internal combustion engine 10 is controlled.

The exhaust system 40 has an exhaust duct 52 in which in the flow direction of an exhaust gas of the internal combustion engine 10 through the exhaust system 40 a turbine 36 of the turbocharger 38 and downstream of the turbine two components 42 . 44 for exhaust aftertreatment of the internal combustion engine 10 namely a particle filter 44 and a three-way catalyst 42 , are arranged. Here is the particle filter 44 preferably provided with a three-way catalytically active coating and as a so-called four-way catalyst 54 educated. Downstream of the second exhaust aftertreatment component 42 . 44 , is in the exhaust duct 52 an exhaust flap 48 arranged, with which the exhaust duct 52 can be locked. In the in 1 illustrated embodiment, the particulate filter 44 upstream of the three-way catalyst 42 arranged. Downstream of the outlet 16 of the internal combustion engine and upstream of the turbine 36 the exhaust gas turbocharger 38 branches at a branching point 46 a high pressure exhaust gas recirculation line 30 from the exhaust system 40 and connects the exhaust duct 52 with the air supply system 20 downstream of the throttle 22 and upstream of the inlet 14 , In the high-pressure exhaust gas recirculation line 30 are a control valve 32 , in particular an exhaust gas recirculation valve 32 , and an exhaust gas cooler 34 arranged. The high pressure exhaust gas recirculation line 30 can be achieved by closing the exhaust gas recirculation valve 32 be locked. The internal combustion engine 10 is a control unit 50 associated with which the amount of in the combustion chambers 12 injected fuel, the position of the throttle 22 and the exhaust gas recirculation valve 32 as well as other engine parameters can be controlled.

In a normal operation of the internal combustion engine 10 is like in 2 represented the exhaust flap 48 opened and the exhaust gas recirculation valve 32 closed, so that the exhaust gas of the internal combustion engine initially through the particulate filter 44 and then flowing through the three-way catalyst. At the same time the internal combustion engine becomes 10 operated with a stoichiometric combustion air ratio (λ = 1) and contained in the exhaust, limited pollutants, in particular carbon monoxide (CO), unburned hydrocarbons (HC) and nitrogen oxides (NOx) on the catalytically active coating of the particulate filter 44 and the three-way catalyst 42 converted. Parallel the particle filter 44 loaded with soot particles. Reaches the loading of the particle filter 44 a critical condition or exceeds the temperature of the particulate filter 44 a critical threshold, so that a subsequent high oxygen input to an uncontrolled Rußabbrand on the particulate filter 44 could lead as part protection measure for the protection of the particulate filter 44 in a coasting operation of the internal combustion engine 10 first the internal combustion engine 10 continues to operate in a fired operation with stoichiometric combustion air ratio (λ = 1) until the exhaust flap 48 is completely closed. Under a coasting operation in this context is a driving operation of a motor vehicle to understand in which the internal combustion engine 10 is towed by the rolling motor vehicle. In overrun mode, the injection of fuel into the combustion chambers 12 of the internal combustion engine 10 prevented, which is referred to as so-called fuel cut. This would be with the exhaust flap open 48 cause the internal combustion engine fresh air with a high oxygen content through the combustion chambers 12 in the exhaust system 40 would promote. But this is at critical loading conditions of the particulate filter 44 and / or high temperatures of the particulate filter 44 to avoid. As soon as the exhaust flap 48 closed and the exhaust gas recirculation valve 32 is opened, the exhaust gas of the internal combustion engine circulates 10 via the high-pressure exhaust gas recirculation line 30 back to the air supply system 20 of the internal combustion engine 10 , and the internal combustion engine 10 will be in one operated unfired overrun operation, where no fuel to the combustion chambers 12 is supplied. Thus, no excess oxygen gets into the exhaust system 40 and uncontrolled soot turnover can be effectively prevented. This condition is in 3 shown. The residual oxygen content in the exhaust gas drops so far that no or only a very low soot oxidation in the particulate filter 44 retained soot particles. In the unfired overrun operation of the internal combustion engine 10 the temperature of the particle filter decreases 44 so that the risk of thermal damage or destruction is minimized. In addition, the throttle is 22 closed in order to minimize the intake side afterflow of fresh air. This arises in the air supply system 20 downstream of the throttle 22 a negative pressure which the purging slope over the high-pressure exhaust gas recirculation line 30 between the exhaust system 40 and the air supply system 20 increases and thus favors the exhaust gas circulation. With a prolonged overrun it is possible, via the lambda control of the three-way catalyst 42 small amounts of fuel in the combustion chambers 12 of the internal combustion engine 10 contribute to the leakage through the air supply system 20 to compensate for penetrating fresh air and the excess oxygen on the three-way catalyst 42 implement. As a result, an accumulation of the oxygen concentration is avoided, whereby the component protection can be effectively maintained even with longer deceleration phases. When the driver returns a desired torque from the internal combustion engine 10 request, the exhaust flap 48 opened again and the exhaust gas recirculation valve 32 is closed to restore normal operation. In this case, in normal operation, a further loading of the particulate filter 44 or a regeneration of the particulate filter 44 respectively. At the same time the internal combustion engine becomes 10 for regeneration of the particulate filter 44 specifically operated with a slight excess air of λ = 1.05 to λ = 1.2, so that a controlled oxidation of the particulate filter 44 retained soot takes place.

In 4 is another embodiment of an internal combustion engine according to the invention 10 shown. With essentially the same structure as 1 are executed in the exhaust system 40 the positions of the three-way catalyst 42 and the particulate filter 44 reversed, that is, the three-way catalyst 42 is downstream of the turbine 36 and upstream of the particulate filter 44 or the four-way catalyst 54 arranged. The exhaust flap 48 is again downstream of the second exhaust aftertreatment components 42 . 44 that is, downstream of the particulate filter 44 arranged.

In 5 is another embodiment of an internal combustion engine according to the invention 10 shown. With essentially the same structure as 1 executed in this embodiment, the exhaust valve 48 downstream of the four-way catalyst 54 and upstream of the three-way catalyst 42 arranged. This is the three-way catalyst 42 in a coasting phase of the internal combustion engine 10 only with a leakage through the exhaust flap 48 flows through, so that an oxygen-containing exhaust gas only to a very slow and delayed loading of the oxygen storage of the three-way catalyst 42 leads. Thus, in a subsequent normal operation, no or only a shortened clearing this oxygen storage of the three-way catalyst 42 necessary due to a motor fat phase.

Alternatively, the position of three-way catalyst 42 and four-way catalyst 54 or particle filter 44 be exchanged so that the particulate filter 44 or the four-way catalyst 54 during the exhaust gas circulation with closed exhaust flap only by the gas leakage through the exhaust flap 48 is flowed through. Thus, the temperature of the particulate filter 44 be lowered in overrun and the risk of uncontrolled Rußabbrandes on the particulate filter 44 be reduced, since this must first be heated to a regeneration temperature after returning to normal operation, before a significant soot on the particulate filter 44 is possible. This embodiment of the invention is in 6 shown.

In 7 are two speed curves of a motor vehicle during a coasting operation of the internal combustion engine 10 shown. At the same time the internal combustion engine becomes 10 in the phases I and III in each case in a normal mode for generating a drive torque of the internal combustion engine 10 for the motor vehicle and in phase II operated in a push operation. In the with <2> marked curve is the internal combustion engine 10 as known in the art in the overrun phase II with a fired overrun and a stoichiometric combustion air ratio λ = 1 operated. The braking power is reduced by the engine drag torque, resulting in only a small reduction in speed and at the same time during the boost phase fuel into the combustion chambers 12 of the internal combustion engine 10 is introduced, which increases the fuel consumption of the motor vehicle. In the curve <1> a speed profile is shown in a method according to the invention, wherein in the overrun phase, the fuel cut is active and no fuel in the combustion chambers 12 of the internal combustion engine 10 is introduced. Thus, an effective component protection for the particulate filter 44 and at the same time an engine braking operation can be realized with a relatively high drag torque.

LIST OF REFERENCE NUMBERS

10

internal combustion engine

12

combustion chamber

14

inlet

16

outlet

18

spark plug

20

Air supply system

22

throttle

26

compressor

28

inlet point

30

Exhaust gas recirculation line

32

Exhaust gas recirculation valve

34

exhaust gas cooler

36

turbine

38

turbocharger

40

exhaust system

42

Three-way catalytic converter

44

particulate Filter

46

branching point

48

exhaust flap

50

Engine control unit

52

exhaust duct

54

Four-way catalyst

λ

Combustion air ratio

t

Time

v

vehicle speed

I

phase 1

II

Phase 2

III

Phase 3

<1>

Vehicle speed with fuel cut

<2>

Vehicle speed with fired overrun

QUOTES INCLUDE IN THE DESCRIPTION

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.

Cited patent literature

• DE 102010039013 A1 [0004]
• DE 102010046896 A1 [0005]
• DE 102012021882 A1 [0006]
• DE 102014118813 A1 [0007]

Claims (10)

Internal combustion engine (10) with an air supply system (20) and an exhaust system (40), wherein the air supply system (20) comprises a throttle valve (22, 24) with which an air supply to the combustion chambers (12) of the internal combustion engine (10) can be controlled and a compressor (26) of an exhaust gas turbocharger (38), and wherein the exhaust system (20) comprises a turbine (36) of the exhaust gas turbocharger (38) and at least one three-way catalyst (42) and a particulate filter (44) downstream of the turbine (36) of the exhaust gas turbocharger (38), and a high pressure exhaust gas recirculation line (30) connecting the exhaust system (40) upstream of the turbine (36) to the air supply system (20) upstream of the compressor (26); characterized in that in the exhaust system (40) downstream of at least one of the exhaust aftertreatment components (42, 44) and downstream of the particulate filter (44) an exhaust flap (48) is arranged Internal combustion engine (10) after Claim 1 characterized in that the throttle (22, 24) is disposed in the air supply system (20) downstream of the compressor (26) and upstream of a discharge point (28) of the high pressure exhaust gas recirculation line (30). Internal combustion engine (10) according to one of Claims 1 to 2 , characterized in that in the high-pressure exhaust gas recirculation line (30), an exhaust gas cooler (34) is arranged. Internal combustion engine (10) according to one of Claims 1 to 3 , characterized in that both the three-way catalyst (42) and the particulate filter (44) are arranged in a near-engine position in the exhaust system (40), wherein the exhaust flap (48) downstream of the exhaust aftertreatment components (42, 44) is. Internal combustion engine (10) according to one of Claims 1 to 4 , characterized in that the particulate filter (44) is designed with a three-way catalytically active coating as a four-way catalyst (54). Internal combustion engine (10) according to one of Claims 1 to 4 characterized in that a first exhaust aftertreatment component (42, 44) is disposed in the exhaust system (40) upstream of the exhaust valve (48) and a second exhaust after treatment component (42, 44) downstream of the exhaust valve (48). Internal combustion engine (10) according to one of Claims 1 to 6 , characterized in that in the high-pressure exhaust gas recirculation (30), a control valve (32) is arranged. Method for regeneration of a particulate filter (44) in an exhaust system (40) of an internal combustion engine (10) according to one of Claims 1 to 7 comprising the following steps: - operating the internal combustion engine (10) in a normal operation, wherein the particulate filter (44) is loaded with soot particles from the exhaust gas of the internal combustion engine (10), - detecting a loading state and a temperature of the particulate filter (44), and Closing the exhaust flap (48), when in a critical loading state and / or at a critical component temperature of the particulate filter (44) a coasting operation of the internal combustion engine (10) is initiated. Method according to Claim 8 , characterized in that the internal combustion engine (10) as long as with a stoichiometric combustion air ratio (λ = 1) is operated until the exhaust valve (48) is completely closed. Method according to one of Claims 8 or 9 , characterized in that in a coasting phase of the internal combustion engine (10) with the exhaust flap (48) closed fuel in the combustion chambers (12) of the internal combustion engine (10) is introduced.

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