DE102006001852B3 - Internal combustion engine e.g. petrol engine, operating method for motor vehicle, involves determining reference value of secondary air-mass flow by gas pipe and controlling phase-adjusting device depending on reference value - Google Patents

Abstract

The method involves coupling a camshaft with a gas inlet valve and adjusting a phase between the camshaft and a crank shaft. A compressor in a gas pipe is mechanically coupled with a turbine. A reference value of a secondary air-mass flow is determined from a suction part to another suction part by the pipe based on an internal combustion engine`s operating value. A phase-adjusting device is controlled depending on the reference value. An independent claim is also included for a device for operating an internal combustion engine.

Description

The The invention relates to a method and an apparatus for operating an internal combustion engine. The internal combustion engine has an intake tract and an exhaust tract that depends from a switching position of at least one gas inlet valve or a gas outlet valve communicate with a combustion chamber of a cylinder. In the cylinder is axially movable a piston with a crankshaft coupled. The cylinder is assigned an injection valve for metering a fuel mass in the respective combustion chamber of the cylinder. Furthermore, the internal combustion engine has at least one camshaft and a Phase adjusting device. The camshaft is coupled to the gas inlet valve. By the Phase adjustment is a phase between the camshaft and the crankshaft adjustable. Communicated through a gas line dependent from the switching position of a gas line valve of the exhaust system with the intake tract. In the intake tract is an actuator for influencing arranged an air mass flow in the combustion chamber. In a bypass to the actuator, a turbine is arranged. A compressor in the gas line is coupled to the turbine.

From the DE 10 2004 009 290 A1 For example, a method and an apparatus for controlling an internal combustion engine is known. The internal combustion engine has an intake tract, an exhaust tract, an exhaust gas turbocharger, at least one cylinder which communicates with the intake tract depending on the position of a gas inlet valve and which communicates with the exhaust tract in dependence on the position of a gas outlet valve. It also has an injector associated with the cylinder which meters fuel, and an exhaust gas recirculation line via which the exhaust tract communicates with the intake tract depending on the position of an exhaust gas recirculation valve. The exhaust gas recirculation valve is controlled as a function of a rotational speed of a crankshaft and a variable characterizing the load of the internal combustion engine such that a gas mass flows from the intake tract through the exhaust gas recirculation line into the exhaust gas tract.

In the DE 103 57 038 A1 a method and a device for controlling a secondary air flow in the exhaust system of an internal combustion engine for a motor vehicle is described. There are control devices for the evaluation of control and sensor signals of the engine control and for adjusting the secondary air flow available. As a sensor size for inclusion in the control with the control device, the position of the accelerator pedal of the motor vehicle is included for adjusting the secondary leakage current. The device has no phase adjustment, with the aid of a phase between a camshaft and a crankshaft is adjustable.

From the DE 102 52 153 A1 For example, an internal combustion engine having an intake passage is known in which a throttle element is disposed, and further comprising an exhaust system including a gas delivery system having an air driven turbine to which a turbine inlet line and a turbine outlet line are connected. It has a compressor drivable by the turbine with a compressor inlet line and a compressor outlet line, via which gas can be supplied to the exhaust system. There is provided a first actuator downstream of the turbine in the turbine outlet conduit, and a second actuator disposed downstream of the compressor in the compressor outlet conduit. This device also has no phase adjustment, by which a phase between a camshaft and a crankshaft of the internal combustion engine is adjustable.

In the DE 102 51 363 A1 For example, a method and a device for controlling a drive unit, in particular of a vehicle, with an internal combustion engine are proposed, which enable a correct charge control when using a secondary air charger and a diagnosis of the secondary air charger. In this case, secondary air is blown in an exhaust line of the internal combustion engine by means of the secondary air charger. The secondary air charger is driven by a pressure gradient across an actuator for adjusting an air supply from the engine. The actuator is controlled to set a dependent on a turbine of the Sekudärluftladers driving air mass flow corrected air supply to the engine. A phase adjusting device, by means of which a phase between the camshaft and the crankshaft is adjustable, is not provided in this device.

In the DE 102 43 317 A1 is an internal combustion engine with a gas delivery system with a driven by an air flow turbine and a turbine driven by the pump, with which the exhaust system gas can be supplied described. In this case, during a starting process of the internal combustion engine, its fuel injection quantity is set as a function of the delivery rate of the pump. A phase adjusting means with which a phase between a camshaft and a crankshaft of the internal combustion engine is adjustable is not provided.

In the article Peter Lückert, Erhard Rau, Anton Waltner: New V8 gasoline engine from Mercedes -Benz - MTZ 12/2005, year 66, pages 932-941, a phase adjustment for internal combustion engines is described, with the optimization of the mixture preparation by means of kontinuierli camshaft adjustment, the camshafts can be brought into a special position that is ideal for secondary air operation. In this position, hot exhaust gas is returned to the intake manifold. To increase the exhaust gas temperature of the ignition is adjusted in the direction of "late". In order to achieve good mixing of engine exhaust and secondary air, the injection point was placed as close to each outlet valve as possible to the bottom of the outlet channels. Here, during the Ausschiebevorgangs the exhaust gas dynamically creates a negative pressure area, whereby the air is sucked into the exhaust stream and can mix there almost perfectly.

task The invention is a method and an apparatus for operating to provide an internal combustion engine, the or a precise operation the internal combustion engine allows.

The Task is solved by the characteristics of the independent Claims. Advantageous embodiments of the invention are characterized in the subclaims.

The Invention is characterized by a method and an apparatus for operating an internal combustion engine. The internal combustion engine has an intake and an exhaust tract, which depends on a switching position at least one gas inlet valve or a gas outlet valve communicate with a combustion chamber of a cylinder. In the cylinder is axially movable, a piston coupled to a crankshaft.

the Cylinder is associated with an injection valve for metering a fuel mass into the respective combustion chamber of the cylinder. Furthermore, the internal combustion engine at least one camshaft and a phase adjusting device. The camshaft is coupled to the gas inlet valve. By the Phase adjusting is a phase between the camshaft and the crankshaft adjustable. Through a gas line communicates depending on the switching position a gas line valve the exhaust tract with the intake. In the intake tract is an actuator for influencing an air mass flow arranged in the combustion chamber. In a bypass to the actuator is a turbine arranged. A compressor in the gas line is with coupled to the turbine. It becomes a setpoint of a secondary air mass flow determined from the intake tract through the gas line to the exhaust tract dependent of at least one operating variable of the internal combustion engine. The phase adjusting device becomes dependent controlled by the setpoint of the secondary air mass flow.

A Speed of the turbine and thus also the speed of the compressor depends on from a pressure difference of the pressure upstream of the actuator and the Downstream pressure of the actuator. If at a given indicated torque the secondary air mass flow changed must be, so by adjusting the phase, a medium pressure downstream of the actuator and upstream of the gas inlet valve can be specified. This will affect the performance the turbine specified. The secondary air mass flow is used, to unburned residues of the Fuel in the exhaust tract with oxygen of the secondary air mass flow to react. This reaction is exothermic, causing the Exhaust tract heats up. This is preferably after a cold start the internal combustion engine exploited to a catalyst in the exhaust tract to heat up and thus promptly to the cold start of the internal combustion engine a preferably optimal exhaust gas treatment by the catalyst to ensure.

In An advantageous embodiment of the method becomes an actual value the pressure upstream of the Detected actuator. A setpoint of the mean pressure downstream of the Actuator and upstream of the gas inlet valve dependent from the actual value of the pressure upstream of the actuator and dependent on the setpoint of the secondary air mass flow determined. The phase adjuster is used to set the Reference value of the secondary air mass flow dependent from the set value of the mean pressure downstream of the actuator and upstream of the Gas inlet valve controlled. This allows a particularly precise setting the secondary air mass flow.

In a further advantageous embodiment of the method is a Actual value of the mean pressure downstream of the actuator and upstream of the gas inlet valve determined. Furthermore, a mean-pressure correction contribution is determined dependent from the actual value and the set value of the mean pressure downstream of the Actuator and upstream of the gas inlet valve. The phase adjusting device is dependent on controlled the medium-pressure correction contribution. This contributes to one very precise Specifying the secondary air mass flow because, by the regulation of the mean pressure downstream of the actuator and upstream the gas inlet valve possible system tolerances of the internal combustion engine can be compensated.

In a further advantageous embodiment of the method, the desired value of the secondary air mass flow is determined depending on a predetermined desired value of an air / fuel ratio, taking into account the secondary air mass flow and / or dependent on a predetermined desired value of the air mass flow into the combustion chamber and / or depending on a target value of Air / fuel ratio in the combustion chamber. This contributes to a particularly precise determination of the secondary air mass flow.

In a further advantageous embodiment of the method is a Actual value of the secondary air mass flow detected and a fuel mass correction contribution determined depending on the actual value of the secondary air mass flow, the setpoint of the secondary air mass flow and the set point of the air / fuel ratio taking into account the Secondary air mass flow. The setpoint of the fuel mass to be metered depends on the Fuel mass correction contribution, the setpoint of the air / fuel ratio in the combustion chamber and dependent predetermined by the desired value of the air mass flow. This makes possible, the secondary air mass flow already to be considered when determining the fuel mass. This carries to help that independent from the predetermined indicated torque a suitable secondary air mass flow guaranteed is.

The advantageous embodiments of the method are readily available to advantageous embodiments of the device for operating the Internal combustion engine transferable.

The The invention is described below with reference to schematic drawings explained in more detail.

It demonstrate:

1 an internal combustion engine,

2 another view of the internal combustion engine,

3 a program for operating the internal combustion engine,

4 a block diagram of an apparatus for operating the internal combustion engine.

elements same construction or function are cross-figurative with the same Reference number marked.

An internal combustion engine ( 1 ) comprises an intake tract 1 , an engine block 2 , a cylinder head 3 and an exhaust tract 4 , The intake tract 1 preferably includes a throttle 5 and a collector 6 and a suction tube 7 Towards a combustion chamber 9 a cylinder Z1 via an inlet channel in the engine block 2 is guided. The engine block 2 further comprises a crankshaft 8th , which has a connecting rod 10 with the piston 11 of the cylinder Z1 is coupled. In the exhaust tract is preferably a catalyst 29 arranged, which is formed for example as a three-way catalyst.

The cylinder head 3 includes a valve train with gas exchange valves, the gas inlet valves 12 and gas outlet valves 13 are, and associated with these valve actuators 14 . 15 ,

A camshaft 18 is provided ( 2 ), which has a cam 16 includes, on the gas inlet valve 12 acts. A phase adjusting device 20 is provided by means of a phase between the crankshaft 8th and the camshaft 18 can be adjusted. This adjustment of the phase can be done, for example, by increasing a hydraulic pressure in high-pressure chambers of the phase adjusting device 20 or lowering the corresponding pressure, depending on the direction in which the adjustment of the phase is to take place. The phase adjusting device 20 may also be formed in any other manner known to those skilled in the art. The phase is representative of a phase angle between a reference mark on the camshaft 18 and a reference mark on the crankshaft 8th in a reference position of the crankshaft 8th ,

It can also be a second camshaft 18 ' be provided. The second camshaft 18 ' is the respective gas outlet valves 13 assigned.

The cylinder head 3 further comprises an injection valve 22 and a spark plug 23 , Alternatively, the injection valve 22 also in the intake manifold 7 be arranged.

A control device 25 is provided, the sensors are assigned, which detect different parameters and each determine the value of the measured variable. Operating variables include the measured variables and variables derived from the measured variables. The control device 25 determined depending on at least one of the measured variables manipulated variables, which are then converted into one or more control signals for controlling the actuators by means of appropriate actuators. The control device 25 may also be referred to as a device for operating the internal combustion engine.

The sensors are a pedal position transmitter 26 , the accelerator pedal position of an accelerator pedal 27 detected, an air mass sensor 28 that flap an air mass flow upstream of the throttle 5 detected, a throttle position sensor 30 , the opening degree of a throttle valve 5 detected, a temperature sensor 32 , which has an intake air temperature TAM in the intake tract 1 detected, an intake manifold pressure sensor 34 that produces a manifold pressure in the collector 6 detected, a crankshaft sensor 36 which detects a crankshaft angle, which is then assigned a speed N. Further, a camshaft angle sensor 39 provided that detects a camshaft angle. If two camshafts 18 . 18 ' in front are present, is preferred each camshaft 18 . 18 ' a camshaft angle sensor 39 . 40 assigned. It can also be provided a separate sensor for detecting the phase. However, the at least one sensor for detecting the phase is preferred by the camshaft sensor 39 . 40 and / or the crankshaft sensor 36 educated.

ever according to embodiment The invention may be any subset of said sensors be present or it can also additional Sensors be present.

The actuators are, for example, the throttle 5 , the gas inlet and outlet valves 12 . 13 , the phase adjuster 20 , the injection valve 22 , the spark plug 23 , a bypass valve 44 and / or a gas line valve 50 ,

The bypass valve 44 and a turbine 42 are in a bypass 40 to the throttle 5 arranged. The turbine 42 communicates with the intake tract 1 upstream of the throttle 5 depending on a switching position of the bypass valve 44 , The turbine 42 is with a compressor 48 mechanically coupled. The compressor 48 is in a gas pipe 46 arranged. The compressor 48 communicates with the exhaust tract 4 depending on a switching position of the gas line valve 50 , In an alternative embodiment, the bypass valve may 44 and / or the gas line valve 50 at another position in the bypass 40 or in the gas line 46 be arranged. For example, the bypass valve 44 downstream of the turbine 42 or the gas line valve 50 upstream of the compressor 48 be arranged. The gas line 46 can also be used for external exhaust gas recirculation. Furthermore, in addition to the gas line 46 an exhaust gas recirculation line may be formed, through which the exhaust gas tract 4 with the intake tract 1 can communicate.

Next Cylinders Z2 to Z4 are preferably also provided for cylinder Z1. which then associated with appropriate actuators and possibly sensors are. It can but also be provided more cylinders.

If due to the position of the throttle 5 a pressure differential with respect to the pressure upstream of the throttle 5 and downstream of the throttle 5 is present, it can with appropriate position of the bypass valve 44 the turbine 42 be driven depending on the pressure gradient. Will the turbine 42 driven, so the compressor promotes 48 Fresh air from the intake tract 1 to the exhaust tract 4 , This allows a reaction of the oxygen of the fresh air with combustion residues of a fuel mass in the exhaust tract 4 , This reaction turns the exhaust tract 4 heated. This is particularly advantageous promptly to a cold start of the internal combustion engine when the catalyst 29 not yet reached a predetermined minimum temperature. By a targeted heating of the catalyst 29 This is faster to use than without targeted heating.

A program for operating the internal combustion engine is preferably in the control device 25 stored. The program serves to generate a secondary air mass flow from the intake tract 1 over the gas line 46 to the exhaust tract 4 specify and to control the internal combustion engine for setting the predetermined secondary air mass flow. The program is preferably started shortly after the start of the internal combustion engine in a step S1. If necessary, variables are initialized in step S1.

In a step S2, a desired value SAF_SP of the secondary air mass flow is determined as a function of a desired value LAM_SP of an air / fuel ratio in the combustion chamber 9 , a desired value MAF_SP of a mass air flow into the combustion chamber 9 and a target value LAM_SP_EG an air / fuel ratio, taking into account the secondary air mass flow, preferably after the calculation rule specified in step S2.

In a step S3, an actual value P_TPS_UP_AV of the pressure upstream of the throttle valve 5 determined. The actual value P_TPS_UP_AV of the pressure upstream of the throttle valve 5 can be detected for example with a corresponding sensor or determined depending on one of the measured variables. In this embodiment, the pressure is upstream of the throttle 5 the ambient pressure. In an alternative embodiment, the pressure upstream of the throttle may also deviate greatly from the ambient pressure, for example, with a corresponding arrangement of a turbocharger. The throttle 5 is suitable for influencing the air mass flow into the combustion chamber 9 ,

In a step S4, a desired value MAP_SP of a medium pressure downstream of the throttle valve 5 and upstream of the gas inlet valve 12 determined depending on the setpoint SAF_SP of the secondary air mass flow and the actual value P_TPS_UP_AV of the pressure upstream of the throttle valve 5 , The desired value MAP_SP of the medium pressure can also be determined as a function of the intake air temperature TAM. The desired value MAP_SP of the medium pressure can be determined, for example, on the basis of a first medium-pressure characteristic map. In this embodiment, the mean pressure is downstream of the throttle 5 and upstream of the gas inlet valve 12 the pressure in the suction tube 7 and the collector 6 , In an alternative embodiment, further actuators may be provided for influencing the air mass flow into the combustion chamber 9 in the suction pipe 7 and / or the collector 6 be arranged. At each of these other actuators for influencing the air mass flow into the combustion chamber 9 can then be dependent on a position of the other actuators for influencing the air mass flow into the combustion chamber 9 a pressure gradient across the corresponding actuator for influencing the air mass flow in the combustion chamber 9 to adjust. Downstream of the throttle 5 and upstream of the gas inlet valve 12 Thus, several different pressures can occur simultaneously in each case in the flow direction between the corresponding further actuators for influencing the air mass flow into the combustion chamber 9 , These different pressures are, depending on the position of the other actuators for influencing the air mass flow into the combustion chamber 9 , interdependent. This dependence of the different pressures should then when determining the setpoint SAF_SP of the secondary air mass flow and when determining a target value CAM_IN_SP a position of the camshaft 18 be taken into account.

In a step S5, the target value CAM_IN_SP becomes the position of the camshaft 18 determined depending on the setpoint MAP_SP of the mean pressure downstream of the throttle 5 and upstream of the gas inlet valve 12 , The nominal value CAM_IN_SP can be determined, for example, on the basis of a camshaft position characteristic map. The camshaft position map and / or other maps that are used to operate the internal combustion engine may be included, for example, on an engine test bench and / or by a simulation, and preferably in the control device 25 be stored.

As an alternative to the step S4, the processing after the step S3 can also be continued in a step S6. In step S6, a desired value PQ_SP of a pressure quotient is determined as a function of the desired value SAF_SP of the secondary air mass flow and as a function of an intake air temperature TAM. The pressure quotient is the quotient of the mean pressure downstream of the throttle valve 5 and upstream of the gas inlet valve 12 and the pressure upstream of the throttle 5 , The desired value PQ_SP can be determined, for example, on the basis of a turbine characteristic map.

In a step S7, the desired value MAP_SP of the medium pressure downstream of the throttle valve 5 and upstream of the gas inlet valve 12 determined depending on the setpoint PQ_SP of the pressure quotient and dependent on the actual value P_TPS_UP_AV of the pressure upstream of the throttle valve 5 , preferably according to the calculation rule specified in step S7.

In In step S8, the processing can be ended. Preferably however, the edit is looped back into the step S1 continued.

A control and a control for operating the internal combustion engine is explained in more detail below ( 4 ).

A block B1 comprises a first determination unit, which supplies the desired value MAF_SP of the air mass flow into the combustion chamber 9 determined depending on a target value TQI_SP an indexed torque and depending on the speed N of the internal combustion engine, for example based on an air mass flow map and / or according to the steps S6 and S7 of the program for operating the internal combustion engine.

A block B2 comprises a first multiplier unit which transmits a desired value MFF_SP of a fuel mass to be metered as a function of the desired value MAF_SP of the air mass flow into the combustion chamber 9 and depending on a target value LAM_SP of the air-fuel ratio in the combustion chamber 9 , preferably by simple multiplication of the setpoint value MAF_SP of the air mass flow into the combustion chamber 9 with the reciprocal of the target value LAM_SP of the air-fuel ratio in the combustion chamber 9 , The fuel mass desired value MFF_SP may be adjusted depending on a fuel mass correction contribution MFF_SAF_DIF. The adjustment of the target value MFF_SP of the fuel mass is explained in more detail below.

A block B3 comprises a second determination unit which determines the desired value SAF_SP of the secondary air mass flow as a function of a desired value LAM_SP_EG of an air / fuel ratio in the combustion chamber 9 taking into account the secondary air mass flow and depending on the target value LAM_SP of the air / fuel ratio in the combustion chamber 9 and the setpoint MAF_SP of the air mass flow into the combustion chamber 9 , The desired value SAF_SP can be determined, for example, based on a secondary air mass flow characteristic map.

One Block B4 includes a third determination unit that sets the setpoint PQ_SP of the pressure quotient is determined as a function of the setpoint SAF_SP the secondary air mass flow. Preferably, the desired value PQ_SP of the pressure quotient is additionally dependent on the intake air temperature TAM determined. The setpoint PQ_SP of the pressure quotient is preferably determined based on the turbine map.

A block B5 comprises a second multiplier unit, the setpoint MAP_SP of the mean pressure downstream of the throttle 5 and upstream of the gas inlet valve 12 determined depending on the setpoint PQ_SP of the pressure quotient and dependent on the actual value P_TPS_UP_AV of the pressure upstream of the throttle valve 5 , For this purpose, for example, the setpoint PQ_SP of the pressure quotient with the actual value P_TPS_UP_AV of the pressure upstream of the throttle valve 5 multiplied.

A block B6 comprises a pilot control device. The pilot control device determines a pilot control value CAM_IN_PRE of the position of the camshaft 18 depending on the setpoint MAP_SP of the mean pressure downstream of the throttle 5 and upstream of the gas inlet valve 12 and depending on the rotational speed N of the internal combustion engine. The precontrol value CAM_IN_PRE of the position of the camshaft 18 is preferably determined based on a camshaft position map.

A block B7 comprises the internal combustion engine with its actuators and sensors. The block B7 comprises, in particular, the phase adjustment device, which is actuated to set the precontrol value CAM_IN_PRE of the position of the camshaft 18 ,

When using only the blocks B1 to B7 in the manner shown, a precise control of the internal combustion engine is possible. Due to system-related tolerances in the internal combustion engine, the internal combustion engine can react differently to an internal combustion engine of the same type. The system-related tolerances can, for example, different injection holes of the injection valve 22 and / or a different response of the actuators and / or many other design or functional deviations. These system-related tolerances can be compensated by a control of the internal combustion engine. The control of the internal combustion engine with respect to the present invention will be explained in more detail below.

A first summing unit A1 determines a mean-pressure difference MAP_DIF between the setpoint value MAP_SP and the actual value MAP_AV of the mean-pressure downstream of the throttle flap 5 and upstream of the gas inlet valve 12 , The mean-pressure difference MAP_DIF between the setpoint MAP_SP and the actual value MAP_AV of the mean-pressure downstream of the throttle flap 5 and upstream of the gas inlet valve 12 For example, by simply summing the setpoint MAP_SP and the actual MAP_AV value of the mean pressure downstream of the throttle 5 and upstream of the gas inlet valve 12 be determined with appropriate signs. For example, the actual value MAP_AV of the mean pressure downstream of the throttle 5 and upstream of the gas inlet valve 12 received a negative sign before summing.

A block B9 comprises a fourth determination unit which determines the actual value MAP_AV of the mean pressure downstream of the throttle valve 5 and upstream of the gas inlet valve 12 preferably dependent on the speed N and a signal TPS of the throttle position sensor 30 determined. Actual value MAP_AV of the mean pressure downstream of the throttle 5 and upstream of the gas inlet valve 12 is preferably determined by means of a Saugrohrmodell. Alternatively, the actual value MAP_AV of the mean pressure downstream of the throttle 5 and upstream of the gas inlet valve 12 with the intake manifold pressure sensor 34 in the suction pipe 7 be determined.

A block B8 includes a first controller that determines a correction value MAP_COR depending on the mean-pressure difference MAP_DIF between the target value MAP_SP and the actual value MAP_AV of the mean-pressure downstream of the throttle 5 and upstream of the gas inlet valve 12 , The first controller and other controllers are, for example, PID controllers.

A block B10 comprises a conversion unit which has a correction value CAM_IN_COR of the position of the camshaft 18 depending on the MAP_COR correction value of the mean pressure downstream of the throttle valve 5 and upstream of the gas inlet valve 12 determined. The blocks B8 and B10 may alternatively be included in a second controller.

A second summing unit A2 determines the position of the camshaft as a function of the precontrol value CAM_IN_PRE 18 and the correction value CAM_IN_COR of the position of the camshaft 18 the control signal for the phase adjustment. Furthermore, the setting signal for the phase adjusting device in the fourth determination unit in the block B9 for determining the mean pressure downstream of the throttle valve 5 and upstream of the gas inlet valve 12 be used.

A third summation unit A3 determines a difference SAF_DIF of the secondary air mass flow depending on the setpoint SAF_SP of the secondary air mass flow and the actual value SAF_AV of the secondary air mass flow.

A block B11 includes a third controller. The third controller determines a fuel mass correction contribution MFF_SAF_DIF depending on the difference SAF_DIF of the secondary air mass flow and the target value LAM_SP_EG of the air / fuel ratio in the combustion chamber 9 U.N taking into account the secondary air mass flow. The third controller is for example a PID controller.

With a fourth summation unit A4, the setpoint MFF_SP the fuel mass dependent from the fuel mass correction contribution MFF_SAF_DIF be adjusted, preferably by adding the setpoint MFF_SP the fuel mass and the fuel mass correction contribution MFF_SAF_DIF. The fuel mass correction contribution MFF_SAF_DIF may also have a assume negative value.

One Block B12 includes a map correction unit. The map correction unit can preferably with a permanent deviation between the setpoint SAF_SP and the actual value SAF_AV of the secondary air mass flow dependent from the difference SAF_DIF of the setpoint SAF_SP and the actual value SAF_AV of the secondary air mass flow adjust the turbine map by the setpoint in block B4 PQ_SP of the pressure quotient is determined.

Claims (6)

Method for operating an internal combustion engine with - an intake tract ( 1 ) and an exhaust tract ( 4 ), which depends on a switching position of at least one gas inlet valve ( 12 ) or a gas outlet valve ( 13 ) with a combustion chamber ( 9 ) of a cylinder (Z1-Z4) in which axially movable a piston ( 11 ) with a crankshaft ( 8th ), - an injection valve associated with the cylinder (Z1-Z4) ( 22 ) for metering a fuel mass into the respective combustion chamber ( 9 ) of the cylinder (Z1-Z4), - at least one camshaft ( 18 ) connected to the gas inlet valve ( 12 ), - a phase adjusting device ( 20 ), through which a phase between the camshaft ( 18 ) and the crankshaft ( 8th ) is adjustable, - a gas line ( 46 ), by which, depending on the switching position of a gas line valve ( 50 ) the exhaust tract ( 4 ) with the intake tract ( 1 ) communicates, - an actuator in the intake tract for influencing an air mass flow into the combustion chamber ( 9 ), - a turbine ( 42 ), which is arranged in a bypass to the actuator, - a compressor in the gas line, which is mechanically coupled to the turbine, in which a desired value (SAF_SP) of a secondary air mass flow from the intake tract ( 1 ) through the gas line ( 46 ) to the exhaust tract ( 4 ) is determined depending on at least one operating variable of the internal combustion engine and in which the phase adjusting device is controlled depending on the desired value (SAF_SP) of the secondary air mass flow. Method according to Claim 1, in which an actual value (P_TPS_UP_AV) of a pressure upstream of the actuator is detected and in which a desired value (MAP_SP) of a mean pressure downstream of the actuator and upstream of the gas inlet valve ( 12 ) is determined as a function of the actual value (P_TPS_UP_AV) of the pressure upstream of the actuator and of the setpoint value (SAF_SP) of the secondary air mass flow and in which the phase adjustment device for setting the setpoint value (SAF_SP) of the secondary air mass flow depends on the desired value (MAP_SP) of the medium pressure downstream of the actuator and upstream of the gas inlet valve ( 12 ) is driven. Method according to Claim 2, in which an actual value (MAP_AV) of the mean pressure downstream of the actuator and upstream of the gas inlet valve ( 12 ) is determined and in which a mean-pressure correction contribution (MAP_COR) is determined as a function of the actual value and the desired value (MAP_AV, MAP_SP) of the mean pressure downstream of the actuator and upstream of the gas inlet valve ( 12 ) and the phase adjusting device is controlled as a function of the mean-pressure correction contribution (MAP_COR). Method according to one of the preceding claims, wherein the desired value (SAF_SP) of the secondary air mass flow is determined as a function of a predetermined desired value (LAM_SP_EG) of an air / fuel ratio taking into account the secondary air mass flow and / or dependent on a predetermined desired value (MAF_SP) of the air mass flow in the combustion chamber ( 9 ) and / or depending on a desired value (LAM_SP) of an air / fuel ratio in the combustion chamber ( 9 ). The method of claim 4, wherein an actual value (SAF_AV) of the secondary air mass flow is detected and in which a fuel mass correction contribution (MFF_SAF_DIF) is determined depending on the actual value (SAF_AV) of the secondary air mass flow, the setpoint (SAF_SP) of the secondary air mass flow and the setpoint (LAM_SP_EG ) of the air / fuel ratio taking into account the secondary air mass flow and in which the desired mass (MFF_SP) of the fuel mass to be metered is determined depending on the fuel mass correction contribution (MFF_SAF_DIF), the desired value (LAM_SP) of the air / fuel ratio in the combustion chamber ( 9 ) and dependent on the desired value (MAF_SP) of the air mass flow into the combustion chamber ( 9 ). Device for operating an internal combustion engine with - an intake tract ( 1 ) and an exhaust tract ( 4 ) which depends on a switching position of at least one gas inlet valve ( 12 ) or a gas outlet valve ( 13 ) with a combustion chamber ( 9 ) of a cylinder (Z1-Z4) in which axially movable a piston ( 11 ) with a crankshaft ( 8th ), - an injection valve associated with the cylinder (Z1-Z4) ( 22 ) for metering a fuel mass into the respective combustion chamber ( 9 ) of the cylinder (Z1-Z4), - at least one camshaft ( 18 ) connected to the gas inlet valve ( 12 ), - a phase adjusting device ( 20 ), through which a phase between the camshaft ( 18 ) and the crankshaft ( 8th ) is adjustable, - a gas line ( 46 ), by which, depending on the switching position of a gas line valve ( 50 ) the exhaust tract ( 4 ) with the intake tract ( 1 ) communicates, - an actuator in the intake tract for influencing an air mass flow into the combustion chamber ( 9 ), - a turbine ( 42 ), which is arranged in a bypass to the actuator, - a compressor in the gas line, which is mechanically coupled to the turbine, wherein the device is designed to determine a desired value (SAF_SP) of a secondary air mass flow from the intake tract ( 1 ) through the gas line ( 46 ) to the exhaust tract ( 4 ) depending on at least one operating variable of the internal combustion engine and for driving the phase adjusting device depending on the desired value (SAF_SP) of the secondary air mass flow.