DE102018130799A1 - Internal combustion engine and method for operating an internal combustion engine - Google Patents

Abstract

The invention relates to an internal combustion engine (10) for a motor vehicle with at least one combustion chamber (12) and at least one crankshaft (14) for delivering power to the drive wheels of the motor vehicle. The internal combustion engine (10) is connected by its inlet (16) to an intake tract (20) and by its outlet (18) to an exhaust system (40). The internal combustion engine (10) is charged by means of an exhaust gas turbocharger (28) which has a compressor (30) and a turbine (50) which are connected to one another by a drive shaft (36). In order to heat the exhaust gas aftertreatment components (52, 54, 56) to an operating temperature as quickly as possible after a cold start of the internal combustion engine (10), the internal combustion engine (10) and upstream of the turbine (50) are located in the exhaust system (40) downstream of the outlet (18). a combustion chamber (44) is provided, in which a fuel is converted exothermally. The drive shaft (36) of the exhaust gas turbocharger (28) is at least indirectly connected to the crankshaft (14) of the internal combustion engine (10) in order to recover at least part of the exhaust gas energy.

Description

The invention relates to an internal combustion engine with an air supply system and with an exhaust system and a method for operating such an internal combustion engine according to the preamble of the independent claims.

The current exhaust gas legislation, which will become increasingly stringent in the future, places high demands on raw engine emissions and exhaust gas aftertreatment of internal combustion engines. The demands for a further decrease in consumption and the further tightening of the exhaust gas standards with regard to the permissible nitrogen oxide emissions represent a challenge for the engine developers. In gasoline engines, exhaust gas cleaning is carried out in a known manner using a three-way catalytic converter and Catalyst upstream and downstream further catalysts. Exhaust gas aftertreatment systems are currently used in diesel engines, which have oxidation catalysts, catalysts for the selective catalytic reduction of nitrogen oxides (SCR catalyst) and a particle filter for separating soot particles and, if appropriate, further catalysts. Ammonia is preferably used as the reducing agent. Because the use of pure ammonia is complex, a synthetic, aqueous urea solution is usually used in vehicles, which is mixed with the hot exhaust gas stream in a mixing device upstream of the SCR catalytic converter. This mixing heats the aqueous urea solution, the aqueous urea solution releasing ammonia in the exhaust gas duct. A commercially available, aqueous urea solution generally consists of 32.5% urea and 67.5% water.

An important key to minimizing emissions from internal combustion engines is to bring the exhaust gas aftertreatment components to an operating temperature as quickly as possible after starting the internal combustion engine and to operate them permanently in this temperature range in order to enable the most efficient exhaust gas aftertreatment.

In-engine heating measures such as a shift in the ignition angle or the injection timing in the late direction, a late post-injection of fuel or a lambda split operation of the internal combustion engine are known from the prior art, in which a deterioration in the thermal efficiency of the internal combustion engine is deliberately accepted to bring additional energy into the exhaust system and to achieve higher exhaust gas temperatures.

In addition, electrical heating elements and exhaust gas burners are known, with which the exhaust gas flow or a component in the exhaust system can be heated. Electric heating elements and exhaust gas burners have the disadvantage, however, that additional energy is required to heat them up. In addition, such external heating measures have the disadvantage that they increase the exhaust gas temperature, but neither lead to a reduction in raw exhaust emissions nor can they be used to propel the motor vehicle.

From the DE 10 2008 032 601 A1 An exhaust gas aftertreatment system for an internal combustion engine is known, in which an oxidation catalytic converter, an NOx storage catalytic converter downstream of the oxidation catalytic converter, an SCR catalytic converter downstream of the NOx storage catalytic converter, and a particle filter further downstream are arranged. An inlet point for a hot exhaust gas from an exhaust gas burner is provided downstream of the SCR catalytic converter and upstream of the particle filter in order to heat the particle filter to its regeneration temperature.

The DE 10 2016 205 182 A1 discloses an exhaust gas aftertreatment system for an internal combustion engine with a catalytically coated particle filter and a NOx storage catalytic converter, an upstream of the NOx storage catalytic converter being provided with an exhaust gas burner which is operated with a substoichiometric combustion air ratio in order to heat the exhaust gas and simultaneously regenerate the NOx storage catalytic converter with the to allow unburned hydrocarbons from the burner exhaust.

The EP 1 469 173 B1 discloses an exhaust gas aftertreatment system for an internal combustion engine, in which an oxidation catalytic converter, an SCR catalytic converter downstream of the oxidation catalytic converter and a particle filter further downstream are arranged in the flow direction of an exhaust gas through the exhaust gas aftertreatment system. Downstream of the oxidation catalytic converter and upstream of the SCR catalytic converter, a heat exchanger for cooling the exhaust gas flow and downstream of the SCR catalytic converter and upstream of the particle filter are provided in order to heat the exhaust gas flow to a regeneration temperature before entering the particle filter.

The invention is based on the object of reducing the exhaust gas emissions of the internal combustion engine, the energy used to reduce the exhaust gas emissions being able to be used at least in part.

According to the invention, this object is achieved by an internal combustion engine with a crankshaft and solved at least one combustion chamber, the internal combustion engine having its inlet connected to an intake tract, and the internal combustion engine having its outlet connected to an exhaust system. The internal combustion engine has an exhaust gas turbocharger with a compressor and a turbine, which are connected to one another by a shaft. It is provided that a combustion chamber is arranged in the flow direction of an exhaust gas of the internal combustion engine through the exhaust system downstream of the outlet of the internal combustion engine and upstream of the turbine of the exhaust gas turbocharger. It is further provided that the drive shaft of the exhaust gas turbocharger is at least indirectly connected to the crankshaft of the internal combustion engine. At least one exhaust gas aftertreatment component for exhaust gas aftertreatment of an exhaust gas of the internal combustion engine is arranged in the exhaust system downstream of the turbine. In the internal combustion engine according to the invention, it is advantageously possible to implement a heating measure as close as possible to the exhaust gas aftertreatment components in order to minimize the thermal inertia compared to internal engine heating measures. In addition, the waste heat losses through the walls of the exhaust duct are reduced. The heat generated in the combustion chamber can also be used to drive the turbine of the exhaust duct, whereby at least part of this heat can be used. In addition, engine heating measures, which are associated with increased fuel consumption and increased raw emissions of the internal combustion engine, can be omitted for heating the exhaust gas aftertreatment components.

The features listed in the dependent claims provide advantageous further developments and non-trivial improvements to the internal combustion engine specified in the independent claim.

In a preferred embodiment of the invention it is provided that the drive shaft of the exhaust gas turbocharger is connected to an electrical machine, by means of which the compressor of the exhaust gas turbocharger can be driven independently of the exhaust gas flow of the internal combustion engine. The turbine of the exhaust gas turbocharger can be used to generate electrical energy by means of an electrical machine on the drive shaft. This energy can either be used directly or temporarily stored in a battery. As a result, an alternator connected to the internal combustion engine can be relieved, which increases the efficiency of the internal combustion engine and thus improves fuel efficiency. By temporarily storing the energy, there is also the possibility of using this energy, if necessary, to increase the power and / or the torque of the internal combustion engine

In a preferred embodiment of the invention it is provided that the shaft of the exhaust gas turbocharger is mechanically connected to the crankshaft of the internal combustion engine via a through drive. By means of a mechanical through drive, the waste heat from the combustion chamber can be used to drive the crankshaft of the internal combustion engine via the drive shaft of the turbocharger and the through drive. As a result, the output on the crankshaft can be increased, which increases the efficiency of the internal combustion engine. The load point of the internal combustion engine can be shifted in the direction of a load point with lower raw emissions.

Alternatively, it is advantageously provided that the electrical machine is driven by the turbine of the exhaust gas turbocharger and generates electrical current which is transmitted to an electrical drive motor on the crankshaft. As an alternative to a mechanical through drive, an electrical connection between the electrical machine on the drive shaft of the exhaust gas turbocharger and an electrical drive motor, which can be coupled to the crankshaft of the internal combustion engine, can also be provided. In this way, the waste heat from the combustion chamber can also be used to transmit the energy obtained via the turbine to the crankshaft and thus to use it to drive a motor vehicle.

In a further preferred embodiment of the invention, it is provided that a supply line is provided, by means of which the intake tract is connected downstream of the compressor to the combustion chamber in the exhaust system. A part of the fresh air compressed by the compressor of the exhaust gas turbocharger can be branched off from the intake duct by a supply line and fed to the combustion chamber. This enables a simple and inexpensive air supply to the combustion chamber if the internal combustion engine is operated with a stoichiometric or superstoichiometric combustion air ratio. This is particularly useful in gasoline engines in order to reduce raw emissions and to enable the most efficient exhaust gas aftertreatment of the exhaust gases from the internal combustion engine.

It is particularly preferred if a supply valve is arranged in the supply line, via which the fresh air supply to the combustion chamber can be controlled. The air supply to the combustion chamber can be controlled in a simple manner by means of a supply valve. In addition, exhaust gas from the combustion chambers of the internal combustion engine or from the combustion chamber can be prevented from flowing back into the intake duct in an uncontrolled manner. Alternatively, the supply valve can be used for targeted exhaust gas recirculation to reduce the raw emissions in the To reduce combustion chambers of the internal combustion engine.

Alternatively, a secondary air compressor is advantageously provided, which is connected to the combustion chamber in the exhaust system via a secondary air line. As an alternative to an air supply from the intake tract, it is possible to use an external secondary air pump with which the combustion chamber can be supplied with fresh air regardless of the operating state of the internal combustion engine. This is particularly advantageous at low engine speeds and low engine load, because in this operating state the turbine feeds only little power into the drive shaft and only little boost pressure is built up via the compressor of the exhaust gas turbocharger.

In an advantageous embodiment of the invention it is provided that the secondary air compressor is designed as a mechanically driven additional compressor which is driven by the internal combustion engine by means of a traction means, in particular a chain or a belt. A mechanical drive for the secondary air compressor provides a simple and inexpensive option for the drive.

Alternatively, it is provided in a further advantageous embodiment of the invention that the secondary air compressor is designed as an additional electrical compressor. The secondary air compressor can be operated independently of the operating situation of the internal combustion engine by an electric drive, which facilitates control of the secondary air quantity.

It is particularly preferred if a secondary air valve is arranged in the secondary air line, via which the fresh air supply to the combustion chamber can be controlled. The supply of fresh air to the combustion chamber can be controlled in a simple manner by means of a secondary air valve. In addition, exhaust gas from the combustion chambers of the internal combustion engine or from the combustion chamber can be prevented from being released into the environment in an uncontrolled manner. The secondary air valve can in particular comprise a non-return valve in order to enable a fresh air flow in the direction of the combustion chamber, but to prevent an exhaust gas flow against this flow.

• - Einbringen eines Brennstoffs in die Brennkammer,
• - Zufuhr von einem überstöchiometrischen Abgas oder Sekundärluft in die Brennkammer, wobei
• - der Brennstoff mit dem Sauerstoff aus dem überstöchiometrischen Abgas oder der Sekundärluft exotherm in der Brennkammer umgesetzt wird,
• - Beaufschlagen der Turbine des Abgasturboladers mit dem heißen Abgas aus der Brennkammer, wobei die Turbine die Antriebswelle antreibt und wobei
• - die mindestens eine Abgasnachbehandlungskomponente durch das heiße Abgas aus der Brennkammer auf eine Betriebstemperatur aufgeheizt oder auf dieser Betriebstemperatur gehalten wird.

According to the invention, a method for operating an internal combustion engine according to the invention is proposed, which comprises the following steps.

• Introduction of a fuel into the combustion chamber,
• - Supply of a stoichiometric exhaust gas or secondary air into the combustion chamber, wherein
• - The fuel with the oxygen from the superstoichiometric exhaust gas or the secondary air is converted exothermic in the combustion chamber,
• - Applying the hot exhaust gas from the combustion chamber to the turbine of the exhaust gas turbocharger, the turbine driving the drive shaft and wherein
• - The at least one exhaust aftertreatment component is heated by the hot exhaust gas from the combustion chamber to an operating temperature or is kept at this operating temperature.

The method according to the invention makes it possible to heat the exhaust aftertreatment components to an operating temperature promptly after the internal combustion engine has started, and to keep these exhaust aftertreatment components at this operating temperature during the further operation of the internal combustion engine. The waste heat from the combustion chamber can be used to drive the turbine of the exhaust gas turbocharger and thus to recover at least some of the additional energy used.

In an advantageous improvement of this method, it is provided that the drive shaft is at least indirectly connected to the crankshaft of the internal combustion engine, the hot exhaust gas from the combustion chamber driving the crankshaft at least indirectly. As a result, the additional energy which is released during the combustion of the fuel in the combustion chamber can be transmitted to the crankshaft of the internal combustion engine and can thus be used to drive a motor vehicle. Alternatively, the energy from the combustion chamber can be absorbed by the electrical machine and temporarily stored in a battery. If necessary, this energy can then be delivered to an electric drive motor coupled to the crankshaft in order to correspondingly increase the power and / or the torque of the internal combustion engine.

In a preferred embodiment variant of the method it is provided that the internal combustion engine is operated with an over-stoichiometric combustion air ratio, the oxygen necessary for the combustion of the fuel introduced into the combustion chamber being fed to the combustion chamber via the over-stoichiometric exhaust gas. Through an over-stoichiometric Combustion air ratio can easily be supplied to the combustion chamber, an oxygen-rich exhaust gas, with which the fuel can be converted exothermic. This is particularly easy with a diesel engine due to the principle-related excess air. Alternatively, it is also possible with a gasoline engine to carry out the combustion of the fuel in the combustion chambers of the internal combustion engine with an over-stoichiometric combustion air ratio, with a stoichiometric exhaust gas preferably occurring downstream of the combustion chamber in order to achieve maximum-efficient exhaust gas aftertreatment by the exhaust gas aftertreatment components downstream of the turbine of the exhaust gas turbocharger enable.

Alternatively, it is advantageously provided that the intake air is compressed by the compressor and the compressed intake air is supplied to the combustion chamber via the supply line. The internal combustion engine can be operated by heating the exhaust gas through the combustion chamber without internal engine heating measures, whereby the efficiency can be optimized and / or the raw emissions of the internal combustion engine can be minimized.

Furthermore, it is alternatively advantageously provided that secondary air is compressed by a secondary air compressor, the compressed secondary air being fed to the combustion chamber via a secondary air line. By supplying the combustion chamber with air via a secondary air compressor, the amount of fresh air and thus the combustion air ratio in the combustion chamber can be set independently of the operating situation of the internal combustion engine. A sufficient air supply can thus be ensured even if the compressor only builds up a low boost pressure and a fresh air supply via a supply line from the intake tract is not possible.

Unless otherwise stated in the individual case, the various embodiments of the invention mentioned in this application can advantageously be combined with one another.

• 1 ein erstes Ausführungsbeispiel eines erfindungsgemäßen Verbrennungsmotors mit einem Ansaugtrakt und einer Abgasanlage;
• 2 ein zweites Ausführungsbeispiel eines erfindungsgemäßen Verbrennungsmotors mit einem Ansaugtrakt und einer Abgasanlage, wobei die Ansaugleitung mit der Brennkammer über eine Versorgungsleitung verbunden ist;
• 3 ein weiteres Ausführungsbeispiel eines erfindungsgemäßen Verbrennungsmotors mit einem Ansaugtrakt und einer Abgasanlage, wobei eine Sekundärluftpumpe zur Luftversorgung der Brennkammer vorgesehen ist; und
• 4 ein Ablaufdiagramm zur Durchführung eines erfindungsgemäßen Verfahrens zum Betreiben eines Verbrennungsmotors.

The invention is explained below in exemplary embodiments with reference to the accompanying drawings. Show it:

• 1 a first embodiment of an internal combustion engine according to the invention with an intake tract and an exhaust system;
• 2nd a second embodiment of an internal combustion engine according to the invention with an intake tract and an exhaust system, the intake line being connected to the combustion chamber via a supply line;
• 3rd a further embodiment of an internal combustion engine according to the invention with an intake tract and an exhaust system, wherein a secondary air pump is provided for supplying air to the combustion chamber; and
• 4th a flowchart for performing a method according to the invention for operating an internal combustion engine.

1 shows the schematic representation of an internal combustion engine 10th with an intake tract 20th and an exhaust system 40 . The internal combustion engine 10th is a direct injection diesel engine in this embodiment and has a crankshaft 14 and several combustion chambers 12 on. At the combustion chambers 12 is a fuel injector for injecting a fuel into the respective combustion chamber 12 arranged. The internal combustion engine 10th is with his entrance 16 with an intake tract 20th and with its outlet 18th with an exhaust system 40 connected. The internal combustion engine 10th can have a high-pressure exhaust gas recirculation, not shown, with a high-pressure exhaust gas recirculation valve, via which an exhaust gas of the internal combustion engine 10th from the outlet 18th to the entrance 16 can be traced back. At the combustion chambers 12 inlet valves and outlet valves are arranged, with which a fluid connection from the intake tract 20th to the combustion chambers 12 or from the combustion chambers 12 to the exhaust system 40 can be opened or closed.

The intake tract 20th includes an intake duct 22 , in which in the flow direction of fresh air through the intake duct 22 an air filter 24th , downstream of the air filter 24th an air mass meter 26 , in particular a hot film air mass meter, downstream of the air mass meter 26 a compressor 30th of an exhaust gas turbocharger 28 and further downstream an intercooler 32 are arranged. The air mass meter 26 also in a filter housing of the air filter 24th be arranged so that the air filter 24th and the air mass meter 26 form an assembly.

The exhaust system 40 includes an exhaust duct 42 , in which in the flow direction of an exhaust gas of the internal combustion engine 10th through the exhaust duct 42 a combustion chamber 44 , downstream of the combustion chamber 44 a turbine 50 of the exhaust gas turbocharger 28 and further downstream, several exhaust aftertreatment components 52 , 54 , 56 for exhaust gas aftertreatment of the exhaust gases of the internal combustion engine 10th are arranged. The turbine 50 is via a drive shaft 36 with the compressor 30th of the exhaust gas turbocharger 28 connected. It is also on the drive shaft 36 an electrical machine 34 arranged which the compressor 30th independent of the exhaust gas flow of the internal combustion engine 10th can drive or as a generator through the turbine 50 turned and thus the mechanical energy of the exhaust gas turbocharger 28 converted into electrical energy. The drive shaft 36 is through a through drive 38 mechanically with the crankshaft 14 of the internal combustion engine 10th connected so that the drive shaft 36 Energy on the crankshaft 14 can be transmitted and thus can be used to drive a motor vehicle or a work machine. Alternatively or additionally, can be on the crankshaft 14 an electric drive motor 72 be provided by the electrical machine 34 on the drive shaft 36 is supplied with electrical current.

Downstream of the turbine 50 of the exhaust gas turbocharger 28 are several exhaust aftertreatment components 52 , 54 , 56 arranged. The first exhaust gas aftertreatment component is in the flow direction 52 downstream of the turbine 50 a catalyst 52 , in particular an oxidation catalyst or a NOx storage catalyst. Downstream of the catalyst 52 is a dosing module 58 provided with which a reducing agent 70 , especially aqueous urea solution, in the exhaust duct 42 can be dosed. Downstream of the dosing module 58 is an exhaust gas mixer 76 provided for better mixing of the reducing agent with the exhaust gas flow of the internal combustion engine 10th to reach. A particulate filter is located downstream of the exhaust mixer 54 provided with a coating for the selective, catalytic reduction of nitrogen oxides, which has the function of an SCR catalyst 56 having. Alternatively, downstream of the metering module 58 also an SCR catalytic converter 56 and an uncoated particle filter 54 be provided.

The internal combustion engine 10th is with an engine control unit 80 connected, which via signal lines, not shown, to a temperature sensor, a NOx sensor, a differential pressure sensor, to the fuel injectors of the internal combustion engine 10th as well as with the dosing module 58 and the combustion chamber 44 connected is.

The injection quantity as well as the time of injection of the fuel into the combustion chambers 12 of the internal combustion engine 10th , the amount of fuel injected into the combustion chamber 44 and the metering of the reducing agent 70 for the selective catalytic reduction of nitrogen oxides in the exhaust duct 42 is through this engine control unit 80 controlled. Furthermore, the combustion of the fuel in the burner chamber 44 by the engine control unit 80 be activated or deactivated. Through the catalyst 52 nitrogen monoxide (NO) can be oxidized to nitrogen dioxide (NO ₂ ) so that the ratio of nitrogen monoxide (NO) to nitrogen dioxide (NO ₂ ) before entering the SCR catalytic converter 56 or the coated particle filter 54 can be changed to optimize the efficiency of the selective, catalytic reduction.

Alternatively, the internal combustion engine 10th also be designed as a gasoline engine, in which case the catalyst 52 preferably as a three-way catalyst 52 is executed. Furthermore, the particle filter 54 preferably carried out as an uncoated particle filter or as a four-way catalyst with a three-way catalytically active coating. The dosing module is not required 58 in this embodiment.

In 2nd is another embodiment of an internal combustion engine according to the invention 10th shown. With essentially the same structure as for 1 In this exemplary embodiment, a supply line is additionally implemented 46 provided which the intake duct 22 downstream of the compressor 30th of the exhaust gas turbocharger 28 with the combustion chamber 44 in the exhaust system 40 connects. It is in the supply line 46 a supply valve 48 provided with which the fresh air supply into the combustion chamber 44 can be controlled. The feed valve 48 also prevents exhaust from the combustion chamber 44 back into the intake tract uncontrolled 20th flows. The feed valve can 48 can also be used as an exhaust gas recirculation valve to reduce the raw emissions of the internal combustion engine 10th to reduce. They are also downstream of the turbine 50 of the exhaust gas turbocharger 28 an oxidation catalyst 52 or a NOx storage catalyst, downstream of the oxidation catalyst 52 or a particulate filter of the NOx storage catalytic converter 54 and further downstream an SCR catalyst 56 intended. It is downstream of the particulate filter 54 and upstream of the SCR catalyst 56 a dosing module 58 arranged with which a reducing agent 70 in the exhaust duct 42 upstream of the SCR catalyst 56 can be dosed. The dosing module 58 can be an exhaust mixer 76 be connected downstream to the mixing of the exhaust gas flow with the metered reducing agent 70 to improve.

In 3rd is another embodiment of an internal combustion engine according to the invention 10th shown. With essentially the same structure as for 1 In this exemplary embodiment, an additional secondary air compressor is implemented 60 to supply air to the combustion chamber 44 intended. The secondary air compressor 60 is via a secondary air line 66 with an inlet to the combustion chamber 44 connected, being in the secondary air line 66 a secondary air valve 68 is provided with which the air supply to the combustion chamber 44 is controlled. The secondary air valve also prevents 68 that exhaust from the combustion chamber 44 flows uncontrolled into the environment. The secondary air compressor 60 is preferably as electrical driven secondary air compressor 62 executed. Alternatively, the secondary air compressor 60 also as a mechanical additional compressor 64 be carried out, the mechanical auxiliary compressor by a traction means, in particular by a belt or a chain with the internal combustion engine 10th is connected and driven by it. Furthermore, this embodiment differs in that it is downstream of the turbine 50 of the exhaust gas turbocharger 28 a catalyst 52 , in particular an oxidation catalyst or a NOx storage catalyst, downstream of the catalyst 52 a particle filter 54 with a coating for the selective, catalytic reduction of nitrogen oxides and further downstream an SCR catalytic converter 56 are arranged. It is downstream of the catalyst 52 and upstream of the particulate filter 54 a first dosing module 58 for dosing a reducing agent 70 provided which a first exhaust mixer 76 is connected downstream. Downstream of the particle filter 54 and upstream of the SCR catalyst 56 is a second dosing module 74 provided which a second exhaust mixer 78 is connected downstream.

Alternatively, the exhaust mixer 76 , 78 also omitted in all exemplary embodiments, if also without the respective exhaust gas mixer 76 , 78 sufficient mixing of reducing agents 70 and exhaust gas from the internal combustion engine 10th is achieved.

In 4th is a flowchart for a method according to the invention for operating such an internal combustion engine 10th shown. In a first method step <100>, a fuel, in particular the fuel of the internal combustion engine 10th , and oxygen-rich exhaust gas or fresh air into the combustion chamber 44 brought in. In a second process step <110>, this fuel-air mixture is ignited and in a process step <120> conducts combustion in the combustion chamber 44 a. Continuous combustion is preferably provided to ensure uniform energy input into the exhaust system 20th to ensure and the exhaust aftertreatment components 52 , 54 , 56 to heat up as quickly as possible to an operating temperature in a process step <140>. The hot exhaust gas drives out of the combustion chamber 44 in a process step <150> in addition to the exhaust gas flow of the internal combustion engine 10th the turbine 50 of the exhaust gas turbocharger 28 causing the waste heat from the combustion chamber 44 can be recovered at least in part.

Reference symbol list

10th

Internal combustion engine

12

Combustion chamber

14

crankshaft

16

inlet

18th

Outlet

20th

Intake tract

22

Intake duct

24th

Air filter

26

Air mass meter

28

Exhaust gas turbocharger

30th

compressor

32

Intercooler

34

electrical machine

36

drive shaft

38

Through drive

40

Exhaust system

42

Exhaust duct

44

Combustion chamber

46

supply line

48

Supply valve / check valve

50

turbine

52

Oxidation catalytic converter / NOx storage catalytic converter / three-way catalytic converter

54

Particle filter

56

SCR catalytic converter

58

Dosing element

60

Secondary air compressor

62

additional electrical compressor

64

mechanical additional compressor

66

Secondary air line

68

Secondary air valve

70

Reducing agent

72

electric drive motor

74

second dosing module

76

Exhaust mixer

78

Exhaust mixer

80

Control unit

QUOTES INCLUDE IN THE DESCRIPTION

This list of documents listed by the applicant has been generated automatically and is only included 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.

Patent literature cited

• DE 102008032601 A1 [0006]
• DE 102016205182 A1 [0007]
• EP 1469173 B1 [0008]

Claims (15)

Internal combustion engine (10) with a crankshaft (14) and at least one combustion chamber (12), the internal combustion engine (10) having its inlet (16) being connected to an intake tract (20), and the internal combustion engine (12) having its outlet ( 18) is connected to an exhaust system (40) and to an exhaust gas turbocharger (28) with a compressor and a turbine (50) which are connected to one another by a drive shaft (36), characterized in that in the flow direction of an exhaust gas of the internal combustion engine ( 10) a combustion chamber (44) is arranged through the exhaust system (40) downstream of the outlet (18) of the internal combustion engine (10) and upstream of the turbine (50) of the exhaust gas turbocharger (28), the drive shaft (36) of the exhaust gas turbocharger (28) at least indirectly with the crankshaft (14) of the internal combustion engine (10), and wherein in the exhaust system (40) downstream of the turbine (50) at least one exhaust gas aftertreatment component (52, 54, 56) for exhaust gas aftertreatment an exhaust gas of the internal combustion engine (10) is arranged. Internal combustion engine (10) after Claim 1 , characterized in that the drive shaft (36) of the exhaust gas turbocharger (28) is connected to an electrical machine (34) via which the compressor (30) can be driven independently of the exhaust gas flow of the internal combustion engine (10). Internal combustion engine (10) after Claim 1 or 2nd , characterized in that the shaft (38) of the exhaust gas turbocharger (28) is mechanically connected to the crankshaft (14) via a through drive (38). Internal combustion engine (10) after Claim 2 , characterized in that the electrical machine (34) generates electrical current which is transmitted to an electrical drive motor (72) on the crankshaft (14). Internal combustion engine (10) according to one of the Claims 1 to 4th , characterized in that a supply line (46) is provided, by means of which the intake tract (20) downstream of the compressor (30) is connected to the combustion chamber (44). Internal combustion engine (10) after Claim 5 , characterized in that a supply valve (48) is arranged in the supply line. Internal combustion engine (10) according to one of the Claims 1 to 4th , characterized in that a secondary air compressor (60) is provided which is connected to the combustion chamber (44) via a secondary air line (66). Internal combustion engine (10) after Claim 7 , characterized in that the secondary air compressor (60) is designed as a mechanical additional compressor (64) which is driven by the internal combustion engine (10) by means of a traction means. Internal combustion engine (10) after Claim 7 , characterized in that the secondary air compressor (60) is designed as an additional electrical compressor (62). Internal combustion engine (10) according to one of the Claims 7 to 9 , characterized in that a secondary air valve (68) is arranged in the secondary air line (66). Method for operating an internal combustion engine (10) according to one of the Claims 1 to 10th , comprising the following steps: - introducing a fuel into the combustion chamber (44), - supplying a superstoichiometric exhaust gas or secondary air into the combustion chamber (44), wherein - the fuel with the oxygen from the superstoichiometric exhaust gas or the secondary air exothermic in the combustion chamber ( 44) is implemented, - applying the hot exhaust gas from the combustion chamber (44) to the turbine (50) of the exhaust gas turbocharger (28), the turbine (50) driving the drive shaft (36), and - the at least one exhaust gas aftertreatment component (52 , 54, 56) is heated to an operating temperature by the hot exhaust gas from the combustion chamber (44) or is kept at this operating temperature. Method for operating an internal combustion engine (10) according to Claim 11 , characterized in that the drive shaft (36) is at least indirectly connected to the crankshaft (14) of the internal combustion engine (10), the hot exhaust gas from the combustion chamber (44) driving the crankshaft (14) at least indirectly. Method for operating an internal combustion engine (10) according to Claim 11 or 12 , characterized in that the internal combustion engine (10) is operated with a superstoichiometric combustion air ratio (Ä> 1), the oxygen necessary for the combustion of the fuel introduced into the combustion chamber (44) being fed to the combustion chamber (44) via the exhaust gas duct (42) . Method for operating an internal combustion engine (10) according to Claim 11 or 12 , characterized in that the intake air is compressed by the compressor (30), the compressed intake air being supplied to the combustion chamber (44) via the supply line (46). Method for operating an internal combustion engine (10) according to Claim 11 or 12 , characterized in that secondary air is compressed by a secondary air compressor (60), the compressed secondary air being fed to the combustion chamber (44) via a secondary air line (66).

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