DE102019124961A1 - Combustion engine with switchable exhaust valves - Google Patents

Abstract

The invention relates to a method for operating an internal combustion engine (10) as a function of a load mode (100, 200), the internal combustion engine having at least two cylinders (1, 2, 3, 4) each with a first (R) and a second (L ) Having exhaust valve, and wherein the method comprises at least the following steps: activating all exhaust valves (R, L) of the cylinders in a high-load mode (200), and activating the first exhaust valve (R) and deactivating the second exhaust valve (L) one or more or all cylinders (1, 2, 3, 4) in a partial load mode (200). The invention also relates to an internal combustion engine, a drive arrangement and a motor vehicle, each operated according to such a method.

Description

The invention relates to a method for operating an internal combustion engine with at least four cylinders, each with a first and at least one second exhaust valve, and an internal combustion engine which is set up to be operated with such a method. The invention also relates to a drive arrangement with such an internal combustion engine and a motor vehicle with such a drive arrangement.

Various operating methods for such internal combustion engines are well known. In addition, internal combustion engines are known in which the gas exchange valves are actuated via switchable rocker arms. In an activated state, such rocker arms interact with a camshaft and can thus operate the gas exchange valves. In a deactivated state, the rocker arms do not operate the gas exchange valves regardless of a position of the camshaft. The exhaust valves can also be deactivated via other mechanisms such as sliding cams.

An internal combustion engine equipped with such rocker arms can therefore assume two operating states. The gas exchange valves are activated in normal operation and deactivated in deactivation operation. The deactivation operation can e.g. B. can be used to reduce an engine drag torque.

If both exhaust valves are either activated jointly or jointly deactivated, the required power cannot be provided in the most efficient way possible in every operating state of the internal combustion engine. Likewise, an optimal ratio of favorable fuel consumption and environmentally friendly emissions behavior cannot be achieved in every operating state.

From the DE 10 2016 219 343 A1 a method is known in which the internal combustion engine is operated as a function of an engine speed and an engine load and comprises at least two cylinders, each with a first and a second exhaust valve. In a full load mode, all exhaust valves of all cylinders are activated, while in a part load mode only the first exhaust valves and not the second exhaust valves of all cylinders are activated.

In modern, supercharged internal combustion engines with more than three cylinders, exhaust manifolds with separate ignition sequences are normally used, which are connected to a multi-flow (twin-flow or segment) turbine of an exhaust gas turbocharger and / or to several exhaust gas turbochargers. This avoids the conflict of objectives between long exhaust control times for good gas exchange at high outputs on the one hand and avoiding the pushing back of residual gas from the cylinder to be ignited at low outputs on the other hand, which can lead to a loss of output and combustion instabilities. With a flow separation, long exhaust control times also bring gas exchange and thus consumption advantages in the partial load.

In return, however, disadvantages in the build-up of back pressure at high power levels, in the thermodynamics of the turbine and in the effort and costs of the associated drive arrangement are accepted.

On this basis, it is an object of the invention to achieve a further improvement in the operation of the internal combustion engines and drive arrangements mentioned at the outset.

This object is achieved by a method with the features of claim 1, an internal combustion engine with the features of claim 5, a drive arrangement with the features of claim 10 and a motor vehicle with the features of claim 14.

According to one aspect of the invention, a method for operating an internal combustion engine as a function of a load mode is provided. The internal combustion engine has at least two cylinders, each with a first and a second exhaust valve.

1. a) Aktivieren aller Auslassventile der Zylinder in einem Hochlastmodus, und
2. b) Aktivieren des ersten Auslassventils und Deaktivieren des zweiten Auslassventils eines, mehrerer oder aller Zylinder in einem Teillastmodus.

The method has at least the following steps:

1. a) activating all exhaust valves of the cylinders in a high load mode, and
2. b) Activating the first exhaust valve and deactivating the second exhaust valve of one, several or all of the cylinders in a partial load mode.

A high-load mode is to be understood in particular as an operating mode of the internal combustion engine that is activated when the internal combustion engine is operated under full load or in a higher partial load range. A partial load mode is to be understood in particular as an operating mode of the internal combustion engine that is activated when the internal combustion engine is operated in a lower partial load range or under low load, zero load or, if necessary, in overrun mode.

In both, in particular all, load modes, the first outlet valves are operated with a first outlet control time which is shorter than a second outlet control time with which the second outlet valves are operated. In particular, the different exhaust control times and thus in particular also different valve lift profiles are achieved by different forms of the cams on a camshaft.

This means that an exhaust gas turbocharger with a mono-scroll turbine can also be used in engines with more than one cylinder group. Because of the shorter exhaust control time of the first exhaust valves - which are operated in partial load mode without opening the second exhaust valves - there is no undesirable crosstalk between the exhausted exhaust gas in the subsequent igniting cylinder even without complete flow separation into the turbine of the exhaust gas turbocharger. A larger exhaust gas pulse on the turbine of an exhaust gas turbocharger and thus a good low-end torque can also be achieved. In high-load operation, on the other hand, the good efficiency of a mono-scroll turbine combined with a high performance potential can be used.

According to another aspect of the invention, an internal combustion engine is provided. The internal combustion engine has at least four, in particular five or six or eight, cylinders, in particular two cylinders of the internal combustion engine being assigned to a cylinder group. Each cylinder has a first and at least one second exhaust valve.

According to one embodiment, the internal combustion engine is a four-cylinder with two cylinder groups or a six-cylinder with three cylinder groups. The cylinder groups are in particular assigned in such a way that cylinders firing at adjacent times are not in a group.

In addition, the internal combustion engine has a control unit which differs from known control units at least in that it is set up to operate the internal combustion engine with a method according to an embodiment of the invention.

According to a further aspect of the invention, a drive arrangement is provided, having an internal combustion engine according to an embodiment of the invention, which has an exhaust manifold for discharging the exhaust gases, and an exhaust gas turbocharger with a mono-scroll turbine, which via the exhaust manifold for exhaust gas guidance with the first and second exhaust valves of the internal combustion engine is connected. A mono-scroll turbine typically has a better degree of efficiency and a higher thermomechanical strength than a twin-flow or segment turbine, while being of the same size. In addition, it has a simpler structure and is therefore cheaper.

According to a further aspect, a motor vehicle with a drive arrangement according to an embodiment of the invention is provided.

The invention is based, inter alia, on the consideration that turbo-charged four-cylinder with the previously known operating strategies to achieve low fuel consumption and environmentally friendly emission values require a flow-separated turbine of the exhaust gas turbocharger and thus also a flow-separated exhaust manifold. By sending the exhaust gases from cylinders firing adjacent in time in this way over long distances, the exhaust gases can be prevented from crosstalking into the next firing cylinder and a long exhaust control time can still be maintained for a good gas exchange.

The invention is based, inter alia, on the idea of resolving the conflict of objectives between a long exhaust control time for a good gas exchange on the one hand and avoiding crosstalk of exhaust gases into the next-igniting cylinder on the other hand.

This is described below using the example of a four-cylinder in-line engine. According to the invention - especially below a switching point to be determined - the valve is deactivated with a long exhaust control time for a good gas exchange in a partial load mode via a valve switch-off of each of the exhaust valves of a cylinder - for example by means of suitably controlled exhaust rocker arms. The outlet switch rocker arms can be switched, for example, by means of a switch shaft or some other suitable device known per se.

The exhaust gas only flows out via the valve with a short opening time, which prevents residual gas from flowing back. In a high-load mode - especially above the switching point - all valves are activated and the advantages of the long opening time in connection with the good efficiency and throughput behavior of a mono-scroll turbine are used. A switchover point between four- and eight-valve operation is determined depending on the operating point in the map and the driver's request according to criteria for maximizing the torque or minimizing consumption. In particular, several engine parameters, which are listed in the next paragraph, individually and / or weighted or combined unweighted, are included in the decision.

According to one embodiment, a switching point with regard to the load mode is determined as a function of one or more engine parameters and / or boundary conditions from the operation and / or the environment of the engine, in particular as a function of an applied engine torque and / or a load requirement and / or a speed and / or a residual gas content and / or a boost pressure requirement and / or a back pressure and / or a center of gravity of the combustion and / or a wastegate position and / or a lift of the intake valves and / or a spread of the intake and exhaust camshafts and / or a rate an external EGR and / or a position of a variable turbine nozzle. According to one embodiment, at least an applied engine torque and a speed are taken into account as engine parameters for determining the load mode. This means that the switchover can take place, depending on the operating point in the map and the driver's request, according to criteria for maximizing torque or minimizing consumption.

The internal combustion engine can thus be operated efficiently with regard to fuel consumption and emissions, since it can be operated in partial load mode if necessary without the disadvantages of the known solutions mentioned.

In the present case, deactivation means in particular that the exhaust valve is closed regardless of a camshaft rotational position. In the present case, activation means in particular that the exhaust valve can be opened and closed as a function of a rotary position of a camshaft. The engine speed is in particular an actual engine speed, and the engine load is in particular an actual engine load.

According to one embodiment, the first exhaust valves, in particular during the first exhaust control time, are operated with a first valve lift curve which differs from a second valve lift curve with which the second exhaust valves are operated, in particular during the second exhaust control time, with regard to a lift maximum and / or a lift gradient differs when opening and / or closing.

In this way, for example, the somewhat stronger throttling can be compensated for by the shorter first outlet control time at partial load. Compensation for the slightly weaker counterpressure reduction than with eight “long” exhaust valve times (with four-cylinder engines) can also be made.

According to one embodiment, the first and second exhaust valves are each assigned a suitable switching device, such as a rocker arm and / or a sliding cam or a fully variable valve train, the drag device of the second exhaust valves being designed as an exhaust rocker arm or a sliding cam arrangement or with a fully variable valve train, so that in particular the second outlet valves can be activated and deactivated by activating and deactivating the respective associated switching device.

According to one embodiment, the first outlet valves cannot be activated and deactivated by activating and deactivating the respective associated switching device. This makes it possible to make the first switching devices simple, so that they are smaller and cheaper.

According to an alternative embodiment, the first outlet valves can be activated and deactivated by activating and deactivating the respective associated switching device - analogously to the second outlet valves - in particular by designing the switching devices of the first outlet valves as outlet rocker arms. This enables a fuel-efficient and emission-optimized engine towing operation.

According to one embodiment, the switching device can actuate the exhaust valve in an activated state in cooperation with a camshaft, and does not actuate the exhaust valve in a deactivated state regardless of a position of the camshaft.

According to one embodiment, the internal combustion engine has an adjusting device, for example an adjusting shaft, which is configured to activate all exhaust valves of all cylinders in a high load mode and to activate the first exhaust valve of the cylinders of one, several or all cylinder groups in a partial load mode and the second Deactivate the exhaust valve of the cylinders of these cylinder groups. This supports operation with one or more deactivated cylinder groups. This operating mode is also provided in a "toggle" mode with alternately deactivated cylinder groups.

According to one embodiment, the mono-scroll turbine has an adjustable stator, that is to say is designed in particular as a VTG turbine. By adjusting the angle of incidence of the turbine blades of the stator, the transmission of impulses from the exhaust gas to the turbine can be optimized and thus the response of the turbine can be improved.

According to one embodiment, the exhaust manifold is a partially flow-separated exhaust manifold. This means in particular that the exhaust gas flows of all cylinders are at least essentially only at a connection point between the exhaust manifold and the Exhaust gas turbochargers are merged. Due to the relatively late merging of the tides, the transmission of momentum to the turbine blades can be improved.

In particular, with regard to an exhaust gas flow in the exhaust manifold, the exhaust gas flows of a first cylinder group (with cylinders that do not ignite immediately one after the other with regard to a cylinder sequence) are combined to form a first group flow and the exhaust gas flows of a second cylinder group to form a second group flow. The two group flows are then brought together, in particular at a distance from the starting points of the respective group flow. In addition to the improved pulse transmission, such a configuration of the exhaust manifold also counteracts the tendency of the system to crosstalk.

• 1 zeigt schematisch eine Antriebsanordnung nach einer beispielhaften Ausführung der Erfindung in einem Teillastmodus.
• 2 zeigt schematisch die Antriebsanordnung nach 1 in einem Hochlastmodus.
• 3 zeigt schematisch einen schaltbaren Schlepphebel eines zweiten Auslassventils in seiner Einbauumgebung eines der Zylinder im Verbrennungsmotor der Antriebsanordnung nach 1.
• 4 zeigt zur Verdeutlichung eines Verfahrens nach einer beispielhaften Ausführung der Erfindung ein Diagramm, in welchem der Hubverlauf der Auslassventile des Verbrennungsmotors der Antriebsanordnung nach 1 über den Kurbelwinkel dargestellt ist.
• 5 zeigt zur Verdeutlichung des Verfahrens ein Diagramm, in welchem die Zuteilung der verschiedenen Lastmodi in Abhängigkeit von einer Motordrehzahl und einem Motormoment dargestellt ist.

Further advantages and possible applications of the invention emerge from the following description in connection with the figures.

• 1 shows schematically a drive arrangement according to an exemplary embodiment of the invention in a partial load mode.
• 2 shows schematically the drive arrangement according to 1 in a high load mode.
• 3 shows schematically a switchable rocker arm of a second exhaust valve in its installation environment of one of the cylinders in the internal combustion engine after the drive arrangement 1 .
• 4th shows a diagram to illustrate a method according to an exemplary embodiment of the invention, in which the stroke profile of the exhaust valves of the internal combustion engine according to the drive arrangement 1 is shown over the crank angle.
• 5 shows a diagram to clarify the method in which the allocation of the various load modes is shown as a function of an engine speed and an engine torque.

The 1 and 2 show a drive arrangement 8th with a four-cylinder internal combustion engine 10 , which has four cylinders 1, 2, 3 and 4. Each of the cylinders 1-4 includes a first exhaust valve R. and a second exhaust valve L. .

In addition, the drive arrangement 8th an exhaust gas turbocharger 12th with a mono-scroll turbine 18th (i.e. with a single inlet on the turbine inlet housing 16 on the turbine 18th of the exhaust gas turbocharger 12th ) on. The first exhaust valves R. as well as the second exhaust valves R. are with the turbine inlet casing 16 via an exhaust manifold 20th flow connectable. Between the exhaust manifold 20th and the turbine inlet casing 16 the turbine 18th branches off a wastegate 22nd to bypass the turbine 18th from.

Downstream of the turbine 18th is an exhaust aftertreatment with a close-coupled catalytic converter 24 and an underfloor catalyst 25th arranged.

A compressor 26th of the exhaust gas turbocharger 12th compresses ambient air by an intake silencer 27 is derived, and leads this via an intercooler 28 and a throttle 29 the cylinders 1-4 to.

The exhaust manifold 20th is designed as a partially flow-separated exhaust manifold, with respect to an exhaust gas flow in the exhaust manifold 20th first the exhaust gas flows of a first cylinder group (cylinders 2 and 3) to a first group flow 5 and the exhaust gas flows of a second cylinder group (cylinders 1 and 4) to a second group flow 6th are brought together, and then spaced from the starting points of the respective group flood 5 or. 6th the two group floods are merged.

In a similar exemplary embodiment, the two cylinder flows of one of the group flows can also be fed individually to another, already combined group flow, or all individual cylinder flows can be brought together at a merging point. Ultimately, it is relevant that the individual flows or the group flows only as close as possible to the turbine inlet casing 16 the turbine 18th of the exhaust gas turbocharger 12th are brought together, in particular only immediately before a branch to a waste gate 22nd .

The first exhaust valves R. and the second exhaust valves L. are made by means of a valve train 30th operated (compare 3 ), a first switching device (not shown, for example designed as a rocker arm) for the first exhaust valves R. and the switching device, designed for example as an outlet rocker arm 32 for the second exhaust valves L. having.

Depending on a load mode, they are either in a high load mode 200 all exhaust valves R. , L. the cylinder 1-4 activated, or in a partial load mode 100 the first exhaust valves R. activated and the second exhaust valves L. deactivated.

The partial load mode 100 is in 1 shown. The second exhaust valves filled in black L. symbolize that this is in partial load mode 100 regardless of the rotation of a camshaft 36 are not actuated (ie, a valve lift of the second exhaust valves L. is in partial load mode 100 constant zero).

The high load mode 200 is in 2 shown. The second exhaust valves filled in white L. symbolize that this is in high load mode 200 accordingly built contour of the camshaft 36 be operated.

To switch between the load modes 100 or. 200 works in the valve train 30th a switchable second rocker arm 32 on a valve stem 34 . The valve stem 34 is representative of each of the second exhaust valves L. shown.

In an activated state, the rocker arm 32 from a camshaft 36 actuated. The rocker arm 32 then moves the valve stem 34 such that the associated second outlet valve L. is opened and closed. In a deactivated state, the rocker arm operates 32 the valve stem 34 regardless of a rotary position of the camshaft 36 Not.

The rocker arm 32 is made by an adjusting device designed as an adjusting shaft in the exemplary embodiment 38 switched between its activated state and its deactivated state. The adjustment device 38 includes a switching contour for this 40 , which is designed as a switching cam in the present embodiment.

The adjusting shaft 38 extends essentially over the entire width of the cylinder 1-4 of the internal combustion engine 10 .

On the adjustment device 38 is one of the number of exhaust valves L. and R. corresponding number of switching contours 40 educated. In the case of the internal combustion engine 10 are on the adjustment device 38 so eight switching contours 40 available.

The adjustment device 38 is designed in the exemplary embodiment so that each of the load modes described 100 , 200 of the internal combustion engine 10 a rotary position of the adjustment device 38 corresponds to.

To implement the invention, it is not absolutely necessary that the first towing devices (not shown) for the first outlet valves R. not be switchable. However, these shift levers can be analogous to the second shift lever 32 be designed if operating cases with a complete engine shutdown, for example during overrun, are to be provided for the internal combustion engine.

In the present embodiment, the first exhaust valves R. with a first exhaust timing T1 operated which is shorter than a second exhaust timing T2 with which the second exhaust valves L. operate. The first exhaust timing T1 is related to a crank angle KW regardless of whether the drive arrangement 8th in partial load mode 100 or high load mode 200 is operated. The second exhaust timing T2 is in high load mode 200 based on the crank angle KW constant. In partial load mode 100 the second exhaust timing is zero because the second exhaust valves L. not be raised.

In the diagram 400 of the 4th is a stroke H of the exhaust valves R. or. L. about the crank angle KW the camshaft 36 registered. This is for the high load mode 200 a first stroke H1 of the first exhaust valves R. and a second stroke H2 the second exhaust valves L. shown.

Due to the shorter first exhaust control time T1 can in partial load mode 100 crosstalk of exhaust gas from the previously ignited cylinder into the cylinder with the currently open first exhaust valve R. be avoided.

In high load mode 200 can due to the longer second exhaust control time T2 on the other hand, a good charge exchange can be ensured.

In the illustrated embodiment (solid lines), both exhaust valves R. and L. with the same maximum stroke Hmax operated.

In another exemplary embodiment, however, it would also be conceivable that the first outlet valves R. can be operated with a stroke curve H1 'with a larger maximum stroke Hmax', in particular in order to compensate for a (possibly even) shorter first outlet control time T1 'during the gas change. A steeper stroke gradient would then also be associated with this. This variant is in the diagram 400 shown with a dashed line.

In the diagram 500 of the 5 is shown in simplified form, like a switching point (here as a switching line S. designed) with regard to the load mode 100 or. 200 depending on several engine parameters M. and or n and or RG and or LB and or GD and or SV and or SW and or HE and or SN and or RA and or PT through the control unit 11 is determined. This list of engine parameters is an example of the design shown. In other versions, other engine parameters can be used in whole or in part.

The diagram 500 shows an engine map in which an engine torque M. about the engine speed n is applied. Below a line of maximum engine torque (limit torque 501 ) the motor torque-speed field is shown by the switching line S. divided into an area in which the internal combustion engine 10 in partial load mode 100 is operated, and an area in which the internal combustion engine 10 High load mode 200 is operated.

This two-dimensional representation is used, among other things, to easily convey the principle of switching between the two load modes 100 or. 200 on the shift line S. . The shift line S. is by means of the control unit 11 depending, among other things, on the engine parameters applied M. and n calculated. In the exemplary embodiment flow into the calculation of the switching point S. various other engine parameters, such as a residual gas content ( RG ) and / or a boost pressure requirement ( LB ) and / or a counter pressure ( GD ) and / or a center of gravity of the combustion ( SV ) and / or a wastegate position ( SW ) and / or a lift of the intake valves ( HE ) and / or a spread of the intake and exhaust camshafts ( SN ) and / or a rate of an external EGR ( RA ) and / or a position ( PT ) of a variable turbine nozzle. Other motor parameters or boundary conditions not mentioned before can also be included in the calculation of the switching point. In different exemplary embodiments, different, in particular also more or less, of the parameters can be taken into account. Switching between the load modes takes place depending on the operating point in the map and the driver's request according to criteria for maximizing torque or minimizing consumption.

By using different exhaust timing T1 and T2 in high load mode 200 and the deactivation of the longer open second exhaust valves L. in partial load mode 100 can be an exhaust gas turbocharger with a mono-scroll turbine 18th even for engines with more than one cylinder group 5 , 6th can be used. A mono-scroll turbine of the same size typically has a better efficiency, higher thermomechanical strength and lower costs than a twin-flow or segment turbine.

1. 1) Ermitteln von Ausprägungen derjenigen Motorkenngrößen 501, 502, die für die Bestimmung des Lastmodus herangezogen werden; 2) Bestimmung des zu verwendenden Lastmodus (also entweder Teillastmodus 100 oder Hochlastmodus 200) in Abhängigkeit von den ermittelten Ausprägungen der herangezogenen Motorkenngrößen; 3) Ansteuern der Verstellwelle 38 zum Aktivieren oder Deaktivieren der zweiten Auslassventile L in Abhängigkeit von dem bestimmten Lastmodus. Falls die Turbine 18 des Abgasturboladers 12 mit einem variablen Leitrad ausgebildet ist, kann die Steuereinheit 11 zudem dazu eingerichtet sein, eine Winkelstellung der Schaufeln des Leitrads unter anderem in Abhängigkeit von dem bestimmten Lastmodus 100 oder 200 zu verstellen.

A control unit 11 of the internal combustion engine 10 is in particular also used as a control unit of the drive arrangement 8th educated. It can also be used as an interactive or separately working part of a higher-level engine control system for the internal combustion engine 10 be trained. For the purposes of the drive arrangement described in the exemplary embodiments 8th the control unit is set up in particular for the following tasks:

1. 1) Determination of the characteristics of those engine parameters 501 , 502, which are used to determine the load mode; 2) Determination of the load mode to be used (i.e. either part load mode 100 or high load mode 200 ) depending on the determined characteristics of the engine parameters used; 3) Controlling the adjusting shaft 38 to activate or deactivate the second exhaust valves L. depending on the particular load mode. If the turbine 18th of the exhaust gas turbocharger 12th is designed with a variable stator, the control unit 11 also be set up to set an angular position of the blades of the stator, inter alia, depending on the specific load mode 100 or 200 to adjust.

List of reference symbols

1-4

cylinder

5

first group flood

6th

second group flood

8th

Drive arrangement

10

Internal combustion engine

11

Control unit

12th

Exhaust gas turbocharger

16

Turbine inlet casing

18th

Mono scroll turbine

20th

Exhaust manifold

22nd

Wastegate

24

close-coupled catalytic converter

25th

Underbody catalytic converter

26th

compressor

27

Intake silencer

28

Intercooler

29

throttle

30th

Valve train

32

Switching device (e.g. switchable, second rocker arm)

34

Valve stem

36

camshaft

38

Adjusting device (e.g. adjusting shaft)

40

Switching contour

100

Partial load mode

200

High load mode

400

Stroke curve-crank angle diagram

500

Engine torque / engine speed diagram

501

Limit motor torque via the speed

R.

first exhaust valves

T1

first, shorter exhaust timing

H1

first stroke

L.

second exhaust valves

T2

second, shorter exhaust timing

H2

second stroke

Hmax

maximum valve lift

KW

Crank angle

M.

Engine torque

n

Engine speed

S.

Switching point, especially switching line

RG

Residual gas content

LB

Boost pressure requirement

GD

Back pressure

SV

Center of gravity of the combustion

SW

Wastegate position

HE

Inlet valve lift

SN

Spread of the inlet and outlet camshafts

RA

Rate of an external EGR

PT

Position of a variable turbine nozzle

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was 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.

Patent literature cited

• DE 102016219343 A1 [0005]

Claims (14)

Method for operating an internal combustion engine (10), depending on a load mode (100, 200), wherein the internal combustion engine has at least four cylinders (1, 2, 3, 4) each with a first (R) and at least one second (L) exhaust valve and wherein the method comprises at least the following steps: a) activating all exhaust valves (R, L) of the cylinders in a high-load mode (200), and b) activating the first exhaust valve (R) and deactivating the second exhaust valve (L) , several or all cylinders (1, 2, 3, 4) in a partial load mode (200), characterized in that the first exhaust valves (R) are operated with a first exhaust control time (T1) which is shorter than a second exhaust control time (T2 ) with which the second exhaust valves (L) are operated. Procedure according to Claim 1 , characterized in that the first exhaust valves (R) are operated with a first valve lift curve (H1) which differs from a second valve lift curve (H2), with which the second exhaust valves (L) are operated, with regard to a lift maximum and / or a lift gradient differs when opening and / or closing. Method according to one of the preceding claims, characterized in that a switching point (S) with regard to the load mode is determined as a function of one or more engine parameters (M, n). Procedure according to Claim 3 , characterized in that at least an applied engine torque (M) and an applied engine speed (n) are taken into account as engine parameters (M, n) for determining the load mode. Internal combustion engine (10), comprising - at least four cylinders (1, 2, 3, 4) each with a first (R) and at least one second (L) exhaust valve, characterized by - a control unit (11) which is set up to control the To operate internal combustion engine with a method according to one of the preceding claims. Internal combustion engine according to Claim 5 , characterized in that the first and second exhaust valves are each assigned a switching device, the switching device of the second exhaust valves (L) being designed as a switchable rocker arm (32) or as a sliding cam arrangement or with a fully variable valve train. Internal combustion engine according to Claim 6 , characterized in that the first outlet valves (R) can also be activated and deactivated by activating and deactivating the respective associated switching device. Internal combustion engine according to Claim 6 or 7th , characterized in that the switching device (32) can actuate the exhaust valve (R, L) in an activated state in cooperation with a camshaft (36), and does not actuate the exhaust valve in a deactivated state regardless of a position of the camshaft. Internal combustion engine according to one of the Claims 6 to 8th , characterized in that with an adjusting device (38) which is set up to activate all exhaust valves (R, L) of all cylinders (1, 2, 3, 4) in a high-load mode (200), and in a part-load mode (200 ) to activate the first exhaust valve (R) of the cylinders of one, several or all cylinder groups and to deactivate the second exhaust valve (L) of the cylinders of these cylinder groups. Drive arrangement (8), comprising an exhaust gas turbocharger (12) with a mono-scroll turbine (18), which is connected to the first (R) and second (L) exhaust valves of the internal combustion engine via the exhaust manifold for exhaust gas routing, and characterized by an internal combustion engine (10) according to one of the Claims 5 to 9 having an exhaust manifold (20) for discharging the exhaust gases. Drive arrangement according to Claim 10 , characterized in that the mono-scroll turbine (18) has an adjustable stator. Drive arrangement according to Claim 10 or 11 , characterized in that the exhaust manifold (20) is a partially flow-separated exhaust manifold. Drive arrangement according to Claim 12 , characterized in that first the exhaust gas flows of a first cylinder group are merged to form a first group flow 5 and the exhaust gas flows of a second cylinder group to form a second group flow 6, and then the two group flows 5, 6 are merged. Motor vehicle, characterized by a drive arrangement (8) according to one of the Claims 10 to 13th .

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