阅读说明：本技术 用于运行增压系统的方法 (Method for operating a supercharging system ) 是由 S.海因肯 A.戈隆齐 M.卡拉布里亚 S.米勒 T.纳塞尔特 于 2020-01-20 设计创作，主要内容包括：本发明涉及一种用于在与内燃机作用连接的变速器的换挡过程期间借助于增压压力调节运行用于内燃机的增压系统的方法,其中,增压系统具有带有压缩机和驱动器的增压级。在此,获取运行状态额定量、尤其由内燃机待产生的扭矩。由运行状态额定量推导出额定增压压力。借助于增压压力调节,增压系统被调整以达到额定增压压力,其中,增压压力调节包括预控制,其考虑用于达到运行状态额定量的点火角度调节和/或气缸抑制。此外描述了一种用于内燃机的增压系统的控制部、一种带有增压系统的内燃机和一种带有内燃机的机动车。(The invention relates to a method for operating a supercharging system for an internal combustion engine during a shifting operation of a transmission operatively connected to the internal combustion engine by means of supercharging pressure regulation, wherein the supercharging system has a supercharging stage with a compressor and a drive. In this case, a setpoint value for the operating state, in particular the torque to be generated by the internal combustion engine, is determined. The setpoint charging pressure is derived from the operating state setpoint quantity. The charging system is adjusted to achieve the target charging pressure by means of a charging pressure regulation, wherein the charging pressure regulation comprises a pilot control which takes into account the ignition angle regulation and/or the cylinder suppression for achieving a target quantity of operating states. Furthermore, a control unit for a supercharging system of an internal combustion engine, an internal combustion engine with a supercharging system and a motor vehicle with an internal combustion engine are described.)

1. Method for operating a supercharging system for an internal combustion engine during a shifting process of a transmission operatively connected to the internal combustion engine by means of a supercharging pressure regulation, wherein the supercharging system has a supercharging stage with a compressor and a drive, with:

-obtaining a nominal quantity of operating state (M)_Moment) In particular the torque to be generated by the internal combustion engine;

-deriving a nominal boost pressure from said operating state nominal amount;

-adjusting the charging system by means of the charging pressure regulation to reach the nominal charging pressure,

wherein the boost pressure regulation comprises a pre-control which takes into account a target quantity (M) for reaching the operating state_Moment) Ignition angle adjustment and/or cylinder suppression.

2. Method according to claim 1, characterized in that the adjustment of the supercharging system is effected via an adjustment assembly, in particular a wastegate valve or a VTG control.

3. The method of claim 2, further comprising:

-determining a firing angle adjustment value for the adjustment assembly; and

-determining a cylinder suppression adjustment value for the adjustment assembly.

4. The method of claim 3, wherein the determining of the firing angle adjustment value further comprises:

-obtaining a firing angle adjustment value;

-determining an absolute part of the ignition angle adjustment value by means of the ignition angle adjustment value; and

-determining a dynamic part of the ignition angle adjustment value from the time variation of the ignition angle adjustment.

5. The method of claim 3, wherein the determination of the cylinder suppression adjustment value further comprises:

-acquiring the number of cylinders to be inhibited;

-determining an absolute portion of the cylinder deactivation adjustment value from the number of cylinders to be deactivated; and

-determining a dynamic part of the cylinder suppression adjustment value from the time variation of the cylinder suppression.

6. A method according to claim 4 or 5, characterized in that the determination of the ignition angle adjustment value is effected by multiplying the absolute and dynamic parts thereof with each other.

7. A method according to claim 5 or 6, characterized in that the determination of the cylinder suppression adjustment value is carried out by adding the absolute and dynamic parts thereof.

8. A method according to any one of claims 3-7, characterised in that the determination of the ignition angle adjustment value and the determination of the cylinder suppression adjustment value are carried out by means of characteristic lines and/or characteristic curves.

9. The method according to claim 8, characterized in that the dynamic part of the ignition angle adjustment value and the absolute and dynamic parts of the cylinder suppression adjustment value are determinable in dependence on the rotational speed of the internal combustion engine.

10. The method of any one of claims 3 to 9, further comprising:

-selecting the ignition angle adjustment value and the cylinder suppression adjustment value depending on an operating point of the internal combustion engine.

11. The method of any of the preceding claims, further comprising:

-acquiring a gear shift process of a transmission operatively connected to the internal combustion engine.

12. Method according to any one of the preceding claims, characterized in that the pre-control additionally takes into account the basic turbocharger equation.

13. Control portion for a supercharging system for an internal combustion engine, characterized in that the control portion is provided for implementing a method according to any one of the preceding claims.

14. Internal combustion engine with a supercharging system with a supercharging stage, wherein the supercharging stage has a compressor and a drive, and with a control according to claim 13.

15. Motor vehicle with an internal combustion engine according to claim 14.

Technical Field

The invention relates to a method for operating a charging system for an internal combustion engine by means of charging pressure regulation, to a control unit for a charging system for an internal combustion engine, to an internal combustion engine having a charging system, and to a motor vehicle having an internal combustion engine.

Background

Supercharging systems for internal combustion engines are generally known, in particular in the motor vehicle sector, in order to supply the cylinders of the internal combustion engine with air with an overpressure for the combustion of fuel.

In order to provide air with an overpressure, for example turbochargers and compressors (kompresor) are known. A turbocharger has a compressor and can be equipped with its own drive for the compressor (for example an electric motor) or it can be operated, for example, with the exhaust gas of an internal combustion engine, wherein the exhaust gas drives a turbine which is operatively connected/coupled to the compressor via a shaft. The latter is also referred to as an exhaust gas turbocharger.

In the case of highly dynamic shifting processes of a transmission (or transmission gear, Schaltgetriebe) and in particular of an automatic transmission, the operating point of the internal combustion engine and accordingly of the turbocharger changes abruptly.

It is known to comfortably design the shifting process in such a way that the torque generated by the internal combustion engine is reduced during the gear ratio, i.e. the shifting, in which the drive and the internal combustion engine and the clutch are decoupled from one another and the transmission changes the torque.

The combustion engine is connected to the transmission via the inertia of the turbocharger, at which point there is no dynamic correction in the control, however, the enthalpy (of the exhaust gas) to the turbine of the turbocharger is suddenly increased, as a result of which the boost pressure rises and possibly overshoots (ü berschwing), the enthalpy increases, since the temperature of the exhaust gas discharged from the cylinder increases due to the ignition angle adjustment in the retard direction, which is demonstrated by the fact that the combustion of the gas mixture in the cylinder no longer proceeds optimally and the engine efficiency is deteriorated, as a result of the combustion of the exhaust gas mixture in the cylinder, and the combustion of the exhaust gas mixture is retarded in the exhaust passage, the more the exhaust gas mixture is retarded, and the more the exhaust gas mixture is burned out, the more the exhaust gas temperature is retarded, and the exhaust gas temperature is retarded, the exhaust gas temperature is pushed back into the exhaust gas passage L.

In particular in the case of gasoline engines controlled by (air) quality, these enthalpy changes lead to an overshoot in the boost pressure (L addruck ü berschwingungen) and an undershoot in the boost pressure (L addrucksuntschwingen), which may have a torque effect.

It is known, for example, from DE 4214648 a1 that the oxygen sensor regulation has a pilot control in order to be able to respond sufficiently quickly to sudden changes in the operating state. Furthermore, DE 4107639 a1 describes a system for regulating and controlling a supercharger of an internal combustion engine, in which a pilot control detects a sudden drop in the load signal and outputs a corresponding signal for closing the wastegate in order to maintain the boost pressure. The setpoint position of the actuating element is determined by the pilot control of DE 102009032372 a1 on the basis of the basic equation of the turbocharger in order to determine the charging pressure at the output of the compressor of the exhaust gas turbocharger. The turbocharger fundamental equation does not take the inertia of the turbocharger into account as a static equation. This equation is calculated in terms of physical model values, however it does not depict, among other things, highly dynamic processes.

Disclosure of Invention

It is an object of the present invention to provide a method which at least partly overcomes the above-mentioned disadvantages. The pre-control (or so-called "pre-control", i.e. Vorsteuerung) should take into account the highly dynamic process described above during the transmission gear change.

This object is achieved by a method according to claim 1, by a control unit according to claim 13, by an internal combustion engine according to claim 14 and by a motor vehicle according to claim 15.

Further advantageous embodiments of the invention result from the dependent claims and the following description of preferred embodiments of the invention.

According to a first aspect, the invention provides a method for operating a supercharging system for an internal combustion engine during a shifting process of a transmission operatively connected to the internal combustion engine by means of supercharging pressure regulation, wherein the supercharging system has a supercharging stage with a compressor and a drive. The method comprises the following steps:

-obtaining (or known as detecting, Erfassen) a nominal quantity of operating state, in particular the torque to be generated by the internal combustion engine;

-deriving a nominal boost pressure from the operating state setpoint quantity;

adjusting the charging system by means of a charging pressure regulation to reach a nominal charging pressure,

the charge pressure regulation comprises a pilot control which takes into account the ignition angle regulation and/or the cylinder inhibition for reaching a nominal operating state quantity.

Here, the above-described shift process of the transmission is represented by "shift process". The transmission is arranged together with the internal combustion engine and is designed in the drive train of a motor vehicle in order to convert the rotational speed/torque of the internal combustion engine into a driving rotational speed/driving force. The transmission can be designed as an "automatic transmission", in which the starting, the selection of the gear ratios and gear steps and the shifting between the gear steps are carried out automatically by the transmission (and its control). The internal combustion engine (engine) may be configured, for example, as a gasoline engine.

The supercharging system may in particular comprise an exhaust-gas turbocharger with Variable Turbine Geometry (VTG) and/or with a wastegate (with at least one bypass valve).

In the case of a shift in an (automatic) transmission, the clutch (of the internal combustion engine, in particular of its output shaft) is opened, the transmission is decoupled from the internal combustion engine and the torque generated by the internal combustion engine is reduced. The acquisition of the nominal operating state quantity just acquires the relatively low setpoint torque of the engine. Additionally or alternatively, a nominal operating state quantity of the engine can also be determined, from which the torque of the engine can be derived.

In order to achieve a target value for the operating state of the engine, in particular a target torque, from which a target charging pressure is derived, a charging system is used, which is adjusted by means of a charging pressure regulation, wherein the charging pressure regulation regulates/controls the charging system as a function of the (target) charging pressure which serves as a control variable (or is referred to as a reference variable, i.e. F ü hrungsgr ö β e).

The concept of monitoring, regulating, controlling, regulating in the context of this invention includes not only control in the sense of the word (without feedback) but also regulation (with one or more regulation loops).

The control behavior of the charge pressure control (or control behavior, i.e., F ü hrungsverhalten) can be improved by the pilot control in such a way that the control quantity requirements to be expected from the operating state target quantity curve and/or the setpoint charge pressure curve are taken into account.

Furthermore, the adjustment of the supercharging system can be effected via an adjusting component (Stellanordnung). For example, the regulating assembly can be configured as a wastegate (valve) or, if the charging system has an exhaust-gas turbocharger with a VTG, as a VTG control. Via the adjusting arrangement, the turbine (drive) output can be adjusted in such a way that the (combustion) exhaust gases flowing out of the combustion chamber by means of the wastegate are guided around the turbine or the orientation of the turbine guide vanes is adjusted by means of the VTG control. Since the compressor output is dependent on the turbine (drive) output, the boost pressure can be influenced by adjusting the adjustment assembly, in particular to achieve the target boost pressure.

In the alternative, a firing angle adjustment value (control amount) and a cylinder suppression adjustment value for the adjustment assembly may be determined. The adjusting components, i.e. the VTG operator and/or the wastegate, can then be adjusted accordingly by means of the determined adjustment values. In other words, the adjustment assembly may be adjusted depending on the ignition angle adjustment and cylinder suppression.

In further embodiments, the determination of the ignition angle adjustment value may further comprise the following:

-obtaining a firing angle adjustment value;

-determining an absolute part of the ignition angle adjustment value by means of the ignition angle adjustment value; and

-determining the dynamic part of the firing angle adjustment value from the temporal change of the firing angle adjustment.

The engine torque is reduced for the shift process and the clutch is opened. This torque reduction can be achieved by ignition angle adjustment. In this case, the ignition angle is set in the retard direction, i.e. the ignition time is shifted backwards (with reference to the crankshaft angle). The acquisition of the ignition angle adjustment value (ignition angle change) then acquires what value or how many degrees the ignition point/ignition angle is changed/moved, in particular in the retard direction. In this case, the torque reduction is dependent at least in part on the firing angle adjustment value. The increase in enthalpy provided to the turbine is also dependent at least in part on the firing angle adjustment value, among other things. The increase in enthalpy provided is thereby linked to an increase in exhaust gas temperature due to the adjustment of the ignition angle in the retard direction.

In order to take into account the boost pressure increase caused by the ignition angle adjustment in the retard direction in the pre-control, the absolute and dynamic part of the ignition angle adjustment value is determined. The enthalpy change does not occur suddenly here, but is subject to a delay therein due to the path between the cylinder outlet and the turbine of the exhaust gas turbocharger. The ignition angle adjustment can also be effected in stages, i.e. the (complete) adjustment of the ignition angle from the starting value to the final value for a particular cylinder is not effected from one working cycle of the cylinder to its next working cycle, but over a plurality of working cycles, so that the desired ignition angle (final value) is reached at the latest at the moment when the clutch is (again) coupled to the engine. In other words, the ignition angle is adjusted in the retard direction in stages with regard to the gas changes, i.e. after each gas change in the cylinder, so that each cylinder fires later than before. Thus, a continuous torque reduction may be made possible. In particular, the ignition angle adjustment can be implemented such that the representation of the time derivative of the ignition angle adjustment resembles a bell curve. By means of the absolute and dynamic part of the actuating value, the pilot control can take into account, in particular, the delay of the enthalpy change and adjust the actuating element accordingly.

In the alternative, the determination of the cylinder suppression adjustment value may further include:

-acquiring the number of cylinders to be inhibited;

-determining the absolute part of the cylinder suppression adjustment value from the number of cylinders to be suppressed; and

-determining a dynamic part of the cylinder inhibition adjustment value from the time variation of the cylinder inhibition.

The reduction in enthalpy provided to the turbine is dependent, inter alia, at least in part on the number of cylinders inhibited. In order to take account of the resulting reduction in the charging pressure by means of the pilot control, the absolute and dynamic portions of the cylinder suppression adjustment value are determined. Therefore, the change in enthalpy resulting from the cylinder suppression does not occur suddenly, but is also subject to the above-mentioned delay. Furthermore, the cylinder inhibition can be realized in particular in such a way that the representation of the time derivative of the cylinder inhibition (or cylinder inhibition process) resembles a bell curve. By adjusting the absolute and dynamic part of the value, the pre-control can take into account, in particular, the delay in enthalpy reduction at least in part and adjust the adjustment component accordingly.

In a further method, the determination of the ignition angle adjustment value can be carried out in such a way that the absolute and dynamic portions thereof are multiplied by one another.

Furthermore, the determination of the cylinder deactivation adjustment value can be carried out in such a way that its absolute and dynamic partial additions (summations) are made.

In a further embodiment, the determination of the ignition angle adjustment value and the determination of the cylinder suppression adjustment value can be carried out by means of characteristic lines and/or characteristic curves. These adjustment values may be stored in characteristic lines and curves depending on the engine speed at the time, the torque of the engine at the time, the time derivative of the firing angle adjustment, the time derivative of the cylinder suppression, the firing angle adjustment value and/or the number of cylinders to be suppressed.

Furthermore, the dynamic part of the ignition angle adjustment value and the absolute and dynamic part of the cylinder suppression adjustment value may be determined depending on the rotational speed of the internal combustion engine. In particular, the characteristic lines/characteristic curves mentioned above can be used for this purpose.

In further embodiments, the ignition angle adjustment value and the cylinder suppression adjustment value may be selected/determined depending on the operating point of the internal combustion engine.

Furthermore, a shifting operation of a transmission (automatic transmission) operatively connected to the internal combustion engine can be detected. A shift schedule enable signal can be generated. It is thus ensured that the boost pressure control takes into account the control value generated by the pilot control only in the case of a shift, i.e. when a shift process of the transmission is detected or a shift process detection signal is present.

In the alternative, the pre-control may also take into account a basic turbocharger equation. In particular, the pre-control may determine the adjustment value depending on a basic turbocharger equation for the adjustment assembly. The adjustment value can be calculated, in particular added, as an ignition angle adjustment value or a cylinder suppression adjustment value.

The basic turbocharger equation is as follows:

here, the,Is the supercharging pressure proportion of the compressor,Is the pressure upstream of the compressor,Is the pressure downstream of the compressor (boost pressure),Is the pressure upstream of the turbine,Is the pressure downstream of the turbine,Is the temperature upstream of the compressor,Is the temperature upstream of the turbine,Is the (exhaust gas) mass flow through the turbine,Is the mass flow of (combustion) air through the compressor,Is a turbineThe isentropic efficiency of,Is the isentropic efficiency of the compressor,Is the mechanical efficiency,Is the special heat capacity of the waste gas,Is the special heat capacity of combustion air,Is an isentropic index of the exhaust gas andis the isentropic index of combustion air.

In order to determine the specific heat capacityAnd isentropic powerThe values for can use a model that provides values depending on the gas composition at the turbine and compressor. Efficiency of,、Andcan also be determined via a model. Pressures upstream and downstream of the turbineCan be determined at least indirectly, if not directly, via the corresponding pressure sensor and/or modelAnd (4) determining.

Furthermore, the following equation for the rated turbine mass flow is derived from the basic turbocharger equation:

the setpoint turbo mass flow can be used to derive a control value depending on the basic turbocharger equation for the control unit, as a result of which the charging pressure can be influenced, in particular to achieve the setpoint charging pressure.

By taking the pre-control additionally into account the basic turbocharger equation, the charge pressure regulation can be at least partially relieved and/or its control characteristics additionally improved.

According to a second aspect, the invention provides a control for a supercharging system of an internal combustion engine, wherein the control is provided for carrying out the method according to the first aspect.

According to a third aspect, the invention provides an internal combustion engine with a supercharging system with a supercharging stage, wherein the supercharging stage has a compressor and a drive, and with a control according to the second aspect.

According to a fourth aspect, the invention provides a motor vehicle with an internal combustion engine according to the third aspect.

Drawings

Embodiments of the invention are now described, by way of example and with reference to the accompanying drawings. Herein, among others:

FIG. 1 schematically illustrates an embodiment of a motor vehicle with an internal combustion engine;

FIG. 2 shows a schematic diagram of a boost pressure regulation for an internal combustion engine according to the method according to the invention;

FIG. 3 shows a pre-control of boost pressure regulation according to the method according to the invention; and is

Fig. 4a shows schematically a curve for the nominal and actual charging pressure without and with the influence of the charging pressure regulation in the case of a shift process with cylinder suppression; and is

Fig. 4b shows schematically a curve for the nominal and actual boost pressure without and with the influence of the boost pressure regulation in the case of a shift process with ignition angle regulation.

List of reference numerals

1 Motor vehicle

3 internal combustion engine (Engine)

5 air pipeline

7 waste gas line

9 supercharging system

11 stages of pressure increase

13 compressor

14 shaft

15 turbine

17 VTG regulating mechanism (adjusting parts)

19 waste gate (adjusting component)

21 control part

25 rating preparation

27 pre-control

29 regulator

31 adjustment assembly

35 Engine speed acquisition

37 obtaining ignition angle adjustment

Determining the time derivative of the ignition angle adjustment 39

41 deriving the number of cylinder restrictions

43 determining the time derivative of cylinder suppression

45 characteristic curve

47 characteristic line

48 modules (or blocks)

49 characteristic line

Characteristic curve 51

53 characteristic line

57 Shift Process acquisition Module

59 switch (or called breaker, namely Schalter)

61 Module

63 Shift procedure acquisition Module

65 switch

EF scaling factor (or called scale factor, Einskalierung faktor)

n_MSpeed (internal combustion engine)

p_2,SollRated boost pressure

p_2,IstActual boost pressure

p_2,Soll,vorRated boost pressure under consideration of pre-control

p_2,Ist,vorActual boost pressure under consideration of pre-control

u_ZW,absIgnition angle adjustment value (Absolute part)

u_ZW,dynIgnition angle adjustment value (dynamic part)

u_ZWIgnition angle adjustment value

u_ZAS,absCylinder restraint adjustment value (Absolute part)

u_ZAS,dynCylinder restraint adjustment value (dynamic part)

u_ZASCylinder restraint adjustment value

u adjusted value

u_regRegulator-based adjustment value

u_vorAdjustment value based on pre-control

u_vor,dynAdjustment value based on pre-control (dynamic part)

u_vor,statAdjustment value based on pre-control (static part)

ZW ignition angle variation

ZW_gradTime derivative of ignition angle change

Number of ZAS suppressed cylinders

ZAS_gradTime derivative of cylinder suppression.

Detailed Description

Fig. 1 schematically shows a motor vehicle 1 having an engine 3, a charging system 9, a clutch 6 and a transmission 10, in particular an automatic transmission. The invention is not limited to a certain engine type. It may be an internal combustion engine, which may be embodied, for example, as a gasoline engine.

The control section 21, which may be designed as an engine controller, is provided, in particular programmed, for controlling the process of the method described in this disclosure. For this purpose, the control unit 21 is also provided for controlling the components necessary for the process.

The engine 3 includes one or more cylinders 4, one of which is shown here. The cylinders 4 are supplied with pressurized (combustion) air by a pressurization system 9.

Via the clutch 6, the torque generated by the engine 3, in particular the clutch torque, can be selectively transmitted to the transmission 20 via the crankshaft 2 of the engine and the drive shaft 8 of the transmission 10. The transmission 10 is designed to transmit the torque of the engine 2 transmitted via the clutch 6 at a desired transmission ratio to the output shaft 12 of the transmission 10.

The booster system 9 comprises a booster stage 11 with a compressor 13. The compressor 13 is driven or operated by a turbine (exhaust gas turbine) 15 with Variable Turbine Geometry (VTG) via a shaft 14. The VTG can be adjusted via the adjusting mechanism 17. The charging system 9 is in the embodiment shown an exhaust gas turbocharger.

The turbine 15 is supplied with exhaust gas from the engine 3 and is driven thereby. A wastegate 19 is provided alternatively/additionally to the VTG. Furthermore, an assembly which is pressurized in multiple stages can be provided. In other words, the supercharging system 9 may have a plurality of supercharging stages 11. Via the regulating structure 17 (and/or via the wastegate 19), the exhaust gas supplied to the turbine 15 and accordingly the power of the compressor 13 can be adjusted.

Fig. 2 shows a charging pressure regulation 23, which is used to operate the engine 3 and in particular the charging system 9 thereof.

The control circuit 23 comprises a setpoint value reserve 25, in which the torque M to be generated by the engine 3 is present_SollIs input as the rated operating state quantity. Rated value reserve 25 is set by rated torque M_SollDeriving the corresponding setpoint charging pressure p_2,SollWhich serves as a control amount of the adjusting portion 23.

The controlled system (or so-called regulation path, Regelstrecke)31 comprises a supercharging system 9 which can be adjusted via an adjustment value (control variable) u, so that it can be adjustedSo that the actual boost pressure p_2,IstIs output as an adjustment amount. In this case, the VTG regulating mechanism 17 (and/or the wastegate 19) is controlled/regulated via the regulating value u. The purpose of the adjusting part 23 is to adjust the amount p_2,IstFollowing (or called tracking, nachzuf ü hren) a predefined control variable p_2,SollAnd thus ideally corresponds to the pressure at the rated boost pressure p_2,SollWith the actual charging pressure p_2,IstThe adjustment deviation (adjustment difference) of the difference between them is as zero as possible. For this purpose, a regulator 29 is provided, the output of which is based on the regulating value u of the regulator_regSo as to adjust the actual boost pressure p_{2, Ist}Adapted to the rated charging pressure p_{2, Soll}. The regulator 29 comprises a PI regulator or is configured as a PI regulator.

To take into account the controlled quantity p_2,SollThe regulating unit 23 also includes a pilot control 27 for the desired setting requirement. The pre-control 27 outputs a pre-control-based adjustment value u_vor. The adjustment value u is determined by a regulator-based adjustment value u_regAnd an adjustment value u based on pre-control_vorAnd (4) forming. Thereby, the controlled system 9 can follow the nominal boost pressure p as quickly as possible_2,SollAnd the regulator 29 regulates the regulation deviation therein, which is derivable from the model accuracy of the pre-control 27.

The pilot control 27 of the charge pressure regulation 23 is shown in detail in fig. 3. The pilot control 27 takes into account the prevailing rotational speed n of the engine 3_M(engine speed), ignition angle adjustment, and cylinder suppression. Ignition angle adjustment and cylinder suppression are considered because an increase in enthalpy provided to the turbine 15 is correlated with ignition angle adjustment and a decrease in enthalpy provided is correlated with cylinder suppression. These enthalpy changes have a power to the pressure boosting stage 9 and accordingly to the actual boost pressure p producible by the pressure boosting stage 9_2,IstThe influence of (c).

The pilot control 27 takes into account the change in the ignition angle ZW and the time derivative ZW of the change in the ignition angle from the ignition angle adjustment_grad. By means of characteristic curve 45 from engine speed n_MAnd ignition angle variation ZW_gradCan determine the ignition angle adjustment value u_ZWDynamic part u of_ZW,dyn. The time derivative ZW of the change in the ignition angle is used here_gradIs similar to a bell-shaped curve. Absolute fraction u_ZW,absCan be determined by the firing angle change ZW and the characteristic line 47. Absolute and dynamic part u_ZW,abs, u_ZW,dynMultiply each other and obtain the ignition angle adjustment value u_ZWIn this way, the above-mentioned enthalpy change is taken into account and the pressure increase stage 9 can be adjusted accordingly in order to compensate for this change in enthalpy.

Furthermore, the number of cylinders to be suppressed ZAS and the time derivative of the cylinder suppression ZAS are taken into account by the cylinder suppression_grad. Cylinder restraint adjustment value u_ZASAlso comprising the absolute part u_ZAS,absAnd a dynamic part u_ZAS,dyn. Absolute fraction u_ZAS,absFrom the characteristic curve 51, the number ZAS of cylinders to be suppressed and the engine speed n are known_MMay be determined. Dynamic part u_ZAS,dynTime derivative ZAS suppressible by cylinder_gradEngine speed n_MAnd characteristic curve 53. Time derivative of cylinder suppression ZAS_gradIs similar to a bell-shaped curve. Cylinder restraint adjustment value u_ZASFrom its part u_ZAS,abs, u_ZAS,dynThe sum of the two results. Finally, the cylinder damping adjustment value u_ZASIs determined in such a way that its absolute and dynamic part u_ZAS,abs, u_ZAS,dynAre added. Cylinder restraint adjustment value u_ZASAnd then loaded (e.g., multiplied) with a scaling factor EF, which may be determined from the characteristic curve 49 with knowledge of the number of cylinders to be suppressed ZAS. Here, the scaling factor EF is a scaling factor with respect to the number of cylinders. Therefore, in the case of full suppression, i.e. when all cylinders are suppressed, the enthalpy supplied to the turbine 15 is substantially no longer present. In the case of partial suppression, enthalpy supply is dependent on the cylinder that is still (not) combusting. By means of the scaling factor EF, the enthalpy supply is taken into account in dependence on the number of suppressed cylinders ZAS.

Depending on the operating point of the engine 3, the torque reduction is effected by adjusting the ignition angle in the retard direction or by cylinder suppression. This means that the torque reduction is achieved either by the ignition angle adjustment in the retard direction or by the cylinder damping. This selection is implemented in block 48.

When there is no firing angle adjustment, the firing angle adjustment value u is set in block 48_ZWAs a zero value input. Accordingly, the output quantity is derived from block 48 (input-side scaling factor EF to be processed at block 48), which is then applied to the cylinder deactivation setpoint value u_ZASThe above. Accordingly, the scaled cylinder suppression adjustment value u is then_zasAs dynamic pre-control-based adjustment value u_vor,dynAs an input amount, to the switch 59.

If the torque reduction is effected via the ignition angle adjustment, a corresponding ignition angle adjustment value u is input at the input side at block 48_ZW. Cylinder suppression adjustment value u because cylinder suppression is not implemented_ZASCorresponding to a zero value and the scaling factor EF has no effect or has no effect, since it only acts in the case of cylinder suppression. Thus, the ignition angle adjustment value u is learned by module 48_ZWWhich corresponds to a cylinder suppression adjustment value u of zero_ZASAdded and then input into the switch 59. Thus, a dynamic pre-control-based adjustment value u is then obtained_vor,dynAdjusting the setting value u in accordance with the ignition angle_ZW。

The switch 59 therefore contains as input a dynamic pre-control-based adjustment value u_vor,dynThis makes it possible to show highly dynamic processes in the charge pressure regulation, that is to say the ignition angle regulation and the cylinder suppression. Dynamic pre-control-based adjustment value u_vor,dynAdjusting the setting value u in accordance with the firing angle_ZWOr cylinder suppression adjustment value u_ZAS。

As a further input variable, switch 59 has an adjustment value u for AT L9 based on an offset (offset)_off. Dynamic pre-control based adjustment u, via block 57_vor,dynAnd an offset-based adjustment value u_offCan be adjusted as an output of the switch 59. Here, the module 57 may be an application function, that is, the user may define the switching condition for the switch 59 by himself.

Switch 65 receives the output of switch 59. In addition, the switch 65 has a value of zero as an input quantity, which is shown as block 61. This zero value corresponds to the position of the adjusting means 17 and/or of the wastegate 19, in which the compression power of the charging system 9 is minimal. In other words, the VTG is set in such a way that the exhaust-gas-induced drive power of the turbine 15 is as low as possible. Alternatively/additionally, wastegate 19 is opened to such an extent that as much exhaust gas as possible is thus guided around turbine 15. Alternatively, the slave module 61, instead of a zero value, may also select an adjustment value such that it maximizes the compression power of the supercharging system 9. When the module 63 registers a gear change operation of the transmission, a corresponding gear change operation registration signal is sent to the switch 65, so that the output of the switch 59 is obtained as the output of the switch 65. If there is no switching process acquisition signal, the quantity provided by module 61 is the output quantity of switch 59.

If a switching process is detected, the module 63 sends a corresponding switching process detection signal to the switch 65, so that the switch 61 outputs the previous output quantity of the switch 59 as an output quantity, i.e. the dynamic pre-control-based adjustment value u_vor,dynOr on the basis of the adjustment value u of the deviation value_off. The output of the switch 65 is used as the regulation value u based on the pre-control_vorIs supplied to the boost pressure regulation 23. In an alternative not shown, pre-control 27 may be configured without switch 59 and module 57. In this alternative, the switch 65 may accordingly have only and accordingly output or transmit the dynamic, pre-control-based adjustment value u on the input side_{vor,dyn off}Or an adjustment value from module 61.

In addition, the module 67 may also determine an adjustment value u for the adjustment assembly by means of the basic turbocharger equation_vor,statWhich may be added to the output of switch 65. Thus, the adjustment value u is based on the pre-control_vorThe basic turbocharger equation may additionally be taken into account.

In fig. 4a, the nominal and actual boost pressure p for the shifting process of the transmission 10 is shown_2,Soll,p_2,IstIs plotted in timeWherein cylinder suppression is achieved during the shifting process and boost pressure regulation 23 is achieved without the pilot control 27. It is possible to identify the actual charging pressure p_2,IstRelatively significantly following the nominal boost pressure p_2,Soll。

If, on the other hand, the pilot control 27 is considered for such a shifting operation, then the target and actual charging pressure p is determined_2,Soll,vor, p_2,Ist,vorCurve in terms of which the actual boost pressure p is recognizable_2,Ist,vorFollows the nominal charging pressure p relatively better_2,Soll,vor。

FIG. 4b shows the above-mentioned curve pair p for a gear shift process_2,Soll,p_2,IstAnd p_2,Soll,vor,p_2,Ist,vorIn which the ignition angle adjustment is effected. It is also recognizable here that the actual charging pressure p takes into account the preliminary control 27_2,Ist,vorFollows the nominal charging pressure p relatively better_2,Soll,vor。

Curve pair p_2,Soll, p_2,IstAnd p_2,Soll,vor, p_2,Ist,vorDepicted at different pressure levels only for better illustration.