Method for operating a supercharging system

Abstract

The invention relates to a method for operating a supercharging system for an internal combustion engine by means of a supercharging pressure adjustment during a gear shift process of a transmission which is operatively connected to the internal combustion engine, wherein the supercharging system has a supercharging stage with a compressor and a drive. Here, an operating state requirement quantity is ascertained, in particular a torque to be generated by the internal combustion engine. A target supercharging pressure is derived from the operating state requirement quantity. By means of the supercharging pressure adjustment, the supercharging system is adjusted to achieve the target supercharging pressure, wherein the supercharging pressure adjustment comprises a pre-control which takes into account a spark angle adjustment and / or a cylinder deactivation for achieving the operating state requirement quantity. 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.

Description

TECHNICAL FIELD

[0001] The present application relates to a method for operating a supercharging system for an internal combustion engine by means of a boost pressure regulation, a control unit for a supercharging system for an internal combustion engine, an internal combustion engine with a supercharging system and a motor vehicle with an internal combustion engine. BACKGROUND

[0002] Supercharging systems for internal combustion engines are generally known, especially in the field of motor vehicles, in order to supply the cylinders of the internal combustion engine with air for the combustion of fuel with overpressure.

[0003] In order to provide air with overpressure, for example turbochargers and compressors are known. Turbochargers have a compressor and can be equipped with their own drive for the compressor, for example an electric motor, or they are operated, for example, with the exhaust gas of the internal combustion engine, wherein the exhaust gas drives a turbine, which is in action connection / coupled with the compressor via a shaft. The latter is also referred to as exhaust turbocharger.

[0004] In the case of highly dynamic gearshift processes in a transmission (also referred to as a gearshift transmission, i.e. Schaltgetriebe) and especially in an automatic transmission, the operating point of the internal combustion engine and accordingly the operating point of the turbocharger is suddenly changed.

[0005] It is known to design the gearshift process comfortably in such a way that the torque generated by the internal combustion engine is reduced during the decoupling of the drive and the internal combustion engine from the clutch and the change in the transmission ratio of the transmission, i.e. during the gearshift.

[0006] The torque can be reduced, for example, by a cylinder deactivation (or also called a cylinder cut-off, Ausblendung), whereby the (exhaust gas) enthalpy at the turbine of the exhaust-gas turbocharger is reduced and this in turn reduces the boost pressure. The coupling of the internal combustion engine to the transmission is delayed after the torque reduction due to the inertia of the turbocharger. There is currently no dynamic correction in this regard in the actuation. Furthermore, there are ways in which the torque reduction that is carried out for a shift process, for example a shift-up process, is not achieved via the above-mentioned cylinder deactivation. For example, the torque reduction can also be achieved via a spark angle adjustment in the retard direction. However, the (exhaust gas) enthalpy onto the turbine of the turbocharger is thereby suddenly increased, whereby the boost pressure rises sharply and can overshoot (or also called over- swing, überschwingt). The enthalpy increases because the temperature of the exhaust gas that is expelled from the cylinder due to the spark angle adjustment in the retard direction rises. This is evidenced by the fact that the combustion of the gas mixture that is in the cylinder no longer takes place optimally and the engine efficiency is worsened. The reason for this is that the combustion of the gas mixture is "delayed" due to the spark angle intervention and thus postponed into the expulsion phase of the gas exchange (Ladungswechsel). Very hot exhaust gas is thereby conducted into the exhaust tract in the expulsion case and the expansion of the mixture combustion no longer supports the downward movement of the piston. The later the spark angle, the more the combustion is postponed into the exhaust phase.

[0007] Just at the mechanical and thermal limits of the exhaust-gas turbocharger, these enthalpy changes cause undesirable operating states of the internal combustion engine. In particular in the case of (air) mass-controlled gasoline engines, these enthalpy changes cause boost pressure overshoots (Ladedrucküberschwingern) and boost pressure undershoots (Ladedruckunterschwingern), which can have a torque effect. This dynamic process cannot be satisfactorily balanced by the current pre-control structure with regulation.

[0008] It is known, for example, from DE 42 14 648 Al that an oxygen sensor regulation has a pre-control in order to be able to respond sufficiently quickly to sudden changes in the operating state. Furthermore, DE 41 07 639 Al describes a system for regulating and controlling a supercharger of an internal combustion engine, in which a pre-control recognizes a sudden drop in the load signal and outputs a corresponding signal for closing the wastegate in order to maintain the boost pressure. The pre-control from DE 10 2009 032 372 Al determines a target position of an adjusting element in order to determine the boost pressure at the output of the compressor of the exhaust-gas turbocharger on the basis of the turbocharger basic equation. The turbocharger basic equation does not take into account the inertia of the turbocharger as a static equation. The equation is calculated with physical model values, however, which do not depict highly dynamic processes, among other things. SUMMARY

[0009] It is an object of the present application to provide a method which at least partially overcomes the above-mentioned disadvantages. Therein, the pre-control (or also referred to as Vorsteuerung) should take into account the above-mentioned highly dynamic processes during the gear shift of the transmission.

[0010] This object is achieved by a method as described below, by a control as described below, by an internal combustion engine as described below and by a motor vehicle as described below.

[0011] Further advantageous design forms of the present application result from the following description of preferred embodiments of the present application.

[0012] According to a first aspect, the present application provides a method for operating a supercharging system for an internal combustion engine during a gear shift process of a transmission which is in operative connection with the internal combustion engine, wherein the supercharging system has a supercharging stage with a compressor and a drive. The method comprises:

[0013] - acquiring (or also referred to as Erfassen) an operating state requirement, in particular a torque to be generated by the internal combustion engine;

[0014] - deriving a required supercharging pressure from the operating state requirement;

[0015] - adjusting the supercharging system by means of a supercharging pressure regulation to achieve the required supercharging pressure,

[0016] wherein the supercharging pressure regulation comprises a pre-control which takes into account a spark angle regulation and / or a cylinder deactivation for achieving the operating state requirement.

[0017] Here, the above-mentioned gear shift process of the transmission is meant by "gear shift process". The transmission is arranged and configured in the drive train of the motor vehicle together with the internal combustion engine in order to transform the rotational speed / torque of the internal combustion engine into a drive rotational speed / drive torque. Here, the transmission can be configured as an "automatic transmission", in which the start, the selection of the transmission ratio and the switching between the transmission stages is automatically carried out by the transmission (and its control). The internal combustion engine (engine) can be configured, for example, as a gasoline engine.

[0018] The supercharging system can in particular comprise a turbocharger with variable turbine geometry (VTG) and / or with a wastegate (with at least one bypass valve).

[0019] In the case of a switching in the (automatic) transmission, a clutch (of the internal combustion engine, in particular of the driven 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 operating state requirement acquires exactly this relatively low required torque of the engine. In addition or alternatively, the operating state requirement of the engine can also be acquired, from which the torque of the engine can be derived.

[0020] In order to achieve the operating state target quantity, in particular the target torque, a target boost pressure is derived therefrom. In order to provide the target boost pressure, a boost system is used, which is adjusted by means of a boost pressure regulation. Here, the boost pressure regulation regulates / controls the boost system in accordance with the (target) boost pressure as a control quantity (or as a reference quantity, i.e. Führungsgröße).

[0021] The concepts of monitoring, adjusting, manipulating, controlling, regulating in the context of the present invention include not only control in the proper sense (without feedback) but also regulation (with one or more regulation loops).

[0022] The boost pressure regulation comprises a pre-control, which takes into account the ignitions angle regulation and / or the cylinder deactivation executable in order to achieve the operating state target quantity. Here, the ignition angle regulation denotes a change in the ignition time. The ignition angle regulation and the cylinder deactivation are notable insofar as the boost pressure regulation causes an enthalpy change in the turbine in that the ignition angle regulation and the cylinder deactivation, for example, increase the exhaust gas temperature and / or reduce the exhaust gas volume. Accordingly, this has an effect on the turbine (drive) power and thus also on the compressor, which generates the boost pressure. As described above, a (excessive) boost pressure drop or boost pressure build-up can thus be generated. By means of the pre-control, the control characteristics (or the control behaviour, i.e. Führungsverhalten) of the boost pressure regulation can be improved in that the control quantity requirement to be expected from the operating state target quantity curve and / or the target boost pressure curve is taken into account.

[0023] Furthermore, the adjustment of the boost system can be effected via an adjustment assembly (Stellanordnung). For example, the adjustment assembly can be configured as a wastegate (valve) or as a VTG manipulation when the boost system has a turbocharger with VTG. Via the adjustment assembly, the turbine (drive) power can be adjusted in that the (combustion) exhaust gas flowing out of the combustion chamber is guided around the turbine by means of the wastegate or the orientation of the turbine guide vanes is adjusted by means of the VTG manipulation. Since the compressor power depends on the turbine (drive) power, the adjustment by means of the adjustment assembly can influence the boost pressure, in particular for achieving the target boost pressure.

[0024] In an alternative, an ignition angle regulation adjustment value (control quantity) and a cylinder deactivation adjustment value can be determined for the adjustment assembly. The adjustment assembly, i.e. the VTG manipulation and / or the wastegate, can then be adjusted accordingly by means of the determined adjustment values. In other words, the adjustment assembly can be adjusted in dependence on the ignition angle regulation and the cylinder deactivation.

[0025] In a further embodiment, the determination of the ignition angle regulation adjustment value can furthermore comprise the following:

[0026] - obtaining a spark angle adjustment value;

[0027] - determining an absolute portion of the spark angle adjustment adjustment value by means of the spark angle adjustment value; and

[0028] - determining a dynamic portion of the spark angle adjustment adjustment value from a temporal change of the spark angle adjustment.

[0029] For the shift process, the torque of the engine is reduced and the clutch is opened. This torque reduction can be achieved by means of the spark angle adjustment. Here, the spark angle is adjusted in the retard direction, that is to say the spark time is moved back (with reference to the crank angle). The spark angle adjustment value (spark angle change) is obtained, which obtains the value or the degrees by which the spark time / spark angle is changed / moved, in particular in the retard direction. Here, the torque reduction depends, in particular at least partially, on the spark angle adjustment value. The increase in the enthalpy provided to the turbine also depends, in particular at least partially, on the spark angle adjustment value. Here, the increase in the enthalpy provided is associated with an increase in the exhaust gas temperature as a result of the spark angle adjustment in the retard direction.

[0030] In order to take into account the increase in the boost pressure caused by the spark angle adjustment in the retard direction in the pre-control, the absolute and dynamic portions of the spark angle adjustment adjustment value are determined. Here, the enthalpy change does not occur abruptly, but is subject to a delay in which the path between the cylinder outlet and the turbine of the exhaust gas turbocharger is delayed. The spark angle adjustment can also be implemented in stages, that is to say the (complete) adjustment of the spark angle from a starting value to an end value for a cylinder is not implemented from one working cycle of the cylinder to the next working cycle thereof, but is implemented over a plurality of working cycles, so that the desired spark angle (end value) is reached at the latest at the time at which the clutch is (again) coupled to the engine. In other words, the spark angle is adjusted in the retard direction in stages with respect to the gas exchange, that is to say after each gas exchange in the cylinder, so that each cylinder is fired later than the previous one. As a result, a continuous torque reduction can be made possible. In particular, the spark angle adjustment can be implemented such that a plot of the time derivative of the spark angle adjustment is similar to a bell curve. By means of the absolute and dynamic portions of the adjustment value, the pre-control can take into account, in particular at least partially, the delay of the enthalpy change and adjust the adjustment components accordingly.

[0031] In an alternative, the determination of the cylinder suppression adjustment value can further comprise:

[0032] - obtaining a number of cylinders to be suppressed;

[0033] - determining an absolute portion of the cylinder suppression adjustment value from the number of cylinders to be suppressed; and

[0034] - determining a dynamic portion of the cylinder suppression adjustment value from a temporal change of the cylinder suppression.

[0035] The reduction of the enthalpy provided to the turbine depends, inter alia, at least partly on the number of cylinders suppressed. In order to take into account the resulting reduction of the charge pressure by means of the pre-control, an absolute and dynamic portion of the cylinder suppression adjustment value is determined. Thus, the enthalpy change resulting from the cylinder suppression does not occur abruptly, but is also subject to the above-mentioned delay. Furthermore, the cylinder suppression can be implemented, inter alia, such that a plot of the time derivative of the cylinder suppression (or of the cylinder suppression process) is similar to a bell curve. By means of the absolute and dynamic portion of the adjustment value, the pre-control can take into account, inter alia, at least partly, the delay of the enthalpy reduction and adjust the adjustment assembly accordingly.

[0036] In a further method, the determination of the ignition angle adjustment adjustment value can be implemented in such a way that its absolute and dynamic portions are multiplied by one another.

[0037] Furthermore, the determination of the cylinder suppression adjustment value can be implemented in such a way that its absolute and dynamic portions are added (cumulative).

[0038] In a further embodiment, the determination of the ignition angle adjustment adjustment value and the determination of the cylinder suppression adjustment value can be implemented by means of characteristic lines and / or characteristic curves. These adjustment values can be stored in the characteristic lines and characteristic curves depending on the engine speed at the time, the torque of the engine at the time, the time derivative of the ignition angle adjustment, the time derivative of the cylinder suppression, the ignition angle adjustment value and / or the number of cylinders to be suppressed.

[0039] Furthermore, the dynamic portion of the ignition angle adjustment adjustment value and the absolute and dynamic portions of the cylinder suppression adjustment value can be determined depending on the rotational speed of the internal combustion engine. In particular, for this purpose the above-mentioned characteristic lines / characteristic curves can be used.

[0040] In a further embodiment, the ignition angle adjustment adjustment value and the cylinder suppression adjustment value can be selected / determined depending on the operating point of the internal combustion engine.

[0041] Furthermore, a gearshift process of a transmission (automatic transmission) acting in conjunction with the internal combustion engine can be acquired. Thereby a gearshift process acquisition signal can be generated. It can thus be ensured that the charge pressure regulation takes into account the adjustment value resulting from the pre-control only in the case of a switch, i.e. when a gearshift process of the transmission is acquired or a gearshift process acquisition signal is present.

[0042] In an alternative, the pre-control can furthermore take into account the turbocharger basic equation. In particular, the pre-control can determine an adjustment value depending on the turbocharger basic equation for the adjustment assembly. This adjustment value can be calculated, inter alia, added, from the ignition angle adjustment adjustment value or the cylinder suppression adjustment value.

[0043] The turbocharger basic equation is as follows:

[0044]

[0045] Herein, is the boost pressure ratio 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 (combustion air) mass flow through the compressor, is the isentropic efficiency of the turbine, is the isentropic efficiency of the compressor, is the mechanical efficiency, is the specific heat capacity of the exhaust gas, is the specific heat capacity of the combustion air, is the isentropic exponent of the exhaust gas and is the isentropic exponent of the combustion air.

[0046] Herein, for determining the values for the specific heat capacities and the isentropic power models can be used which provide values depending on the gas composition at the turbine and the compressor. The efficiencies ,, and can also be determined via models. The pressures upstream and downstream of the turbine can be determined at least indirectly, if not directly, via respective pressure sensors and / or models.

[0047] Further, from the turbocharger basic equation follows the equation for the rated turbine mass flow:

[0048]

[0049] From the rated turbine mass flow adjustment values can be derived depending on the turbocharger basic equation for the adjustment components, by which the boost pressure can be influenced, in particular to achieve a rated boost pressure.

[0050] By additionally considering the turbocharger basic equation by the pre-control, the boost pressure regulation can be at least partially relieved of its burden and / or its control characteristics can be additionally improved.

[0051] According to a second aspect, the invention provides a control unit for a supercharging system of an internal combustion engine, wherein the control unit is configured to implement the method according to the first aspect.

[0052] According to a third aspect, the application 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 unit according to the second aspect.

[0053] According to a fourth aspect, the application provides a motor vehicle with an internal combustion engine according to the third aspect. BRIEF DESCRIPTION OF DRAWINGS

[0054] Embodiments of the application are now described exemplarily and with reference to the accompanying drawings. In this connection:

[0055] Figure 1 An embodiment of a motor vehicle with an internal combustion engine is schematically shown;

[0056] Figure 2 A schematic diagram of a supercharging pressure regulation for an internal combustion engine according to the method according to the application is shown;

[0057] Figure 3 A pre-control of a supercharging pressure regulation according to the method according to the application is shown; and

[0058] Figure 4a Curves for the target and actual supercharging pressure with and without influence of a supercharging pressure regulation in the case of a gear shift process with cylinder deactivation are schematically shown; and

[0059] Figure 4b Curves for the target and actual supercharging pressure with and without influence of a supercharging pressure regulation in the case of a gear shift process with spark angle regulation are schematically shown.

[0060] LIST OF REFERENCE SIGNS

[0061] 1 motor vehicle

[0062] 3 internal combustion engine (engine)

[0063] 5 air line

[0064] 7 exhaust line

[0065] 9 supercharging system

[0066] 11 supercharging stage

[0067] 13 compressor

[0068] 14 shaft

[0069] 15 turbine

[0070] 17 VTG adjustment mechanism (adjustment assembly)

[0071] 19 waste gate (adjustment assembly)

[0072] 21 control unit

[0073] 25 setpoint preparation

[0074] 27 pre-control

[0075] 29 regulator

[0076] 31 adjustment assembly

[0077] 35 engine speed acquisition

[0078] 37 acquisition of ignition angle adjustment

[0079] 39 determination of time derivative of ignition angle adjustment

[0080] 41 acquisition of number of cylinder deactivations

[0081] 43 determination of time derivative of cylinder deactivation

[0082] 45 characteristic curve

[0083] 47 characteristic line

[0084] 48 module (or block)

[0085] 49 characteristic line

[0086] 51 characteristic curve

[0087] 53 characteristic line

[0088] 57 shift process acquisition module

[0089] 59 switch (or schalter)

[0090] 61 module

[0091] 63 shift process acquisition module

[0092] 65 switch

[0093] EF scaling factor (or einskalierungsfaktor)

[0094] n M speed (internal combustion engine)

[0095] p 2,Soll setpoint boost pressure

[0096] p 2,Ist actual boost pressure

[0097] p2,Soll,vor in consideration of the pre-control situation

[0098] p 2,Ist,vor in consideration of the pre-control situation

[0099] u ZW,abs ignition angle regulation adjustment value (absolute part)

[0100] u ZW,dyn ignition angle regulation adjustment value (dynamic part)

[0101] u ZW ignition angle regulation adjustment value

[0102] u ZAS,abs cylinder suppression adjustment value (absolute part)

[0103] u ZAS,dyn cylinder suppression adjustment value (dynamic part)

[0104] u ZAS cylinder suppression adjustment value

[0105] u adjustment value

[0106] u reg regulator-based adjustment value

[0107] u vor pre-control-based adjustment value

[0108] u vor,dyn pre-control-based adjustment value (dynamic part)

[0109] u vor,stat pre-control-based adjustment value (static part)

[0110] ZW ignition angle change

[0111] ZW grad time derivative of the ignition angle change

[0112] ZAS number of suppressed cylinders

[0113] ZAS grad time derivative of the cylinder suppression. DETAILED DESCRIPTION

[0114] Figure 1 A motor vehicle 1 is shown schematically, which has an engine 3, a supercharging system 9, a clutch 6 and a transmission 10, in particular an automatic transmission. The present application is not limited to a certain engine type. An internal combustion engine can be involved, which can be configured as a gasoline engine, for example.

[0115] The control unit 21, which can be designed as an engine controller, is provided, in particular programmed, for controlling the procedure of the method described in this disclosure. To this end, the control unit 21 is furthermore provided for controlling the components necessary for the procedure.

[0116] The engine 3 comprises one or more cylinders 4, one of which is shown here. The cylinder 4 is supplied with pressurized (combustion) air by a supercharging system 9.

[0117] 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 configured to continue the transmission of the torque of the engine 2, which is transmitted via the clutch 6, to the driven shaft 12 of the transmission 10 with a desired transmission ratio.

[0118] The supercharging system 9 comprises a supercharging stage 11 with a compressor 13. The compressor 13 is driven or operated via a shaft 14 by a turbine (exhaust gas turbine) 15 with variable turbine geometry (VTG). The VTG can be adjusted via an adjusting mechanism 17. The supercharging system 9 is an exhaust gas turbocharger in the embodiment shown.

[0119] The turbine 15 is supplied with and driven by exhaust gas from the engine 3. In addition or alternatively to the VTG, a wastegate 19 is provided. A multi-stage supercharging assembly can furthermore be provided. In other words, the supercharging system 9 can have a plurality of supercharging stages 11. Via the adjusting mechanism 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.

[0120] Figure 2 A supercharging pressure regulation 23 is shown, which is used to operate the engine 3 and in particular the supercharging system 9 thereof.

[0121] The regulating loop 23 comprises a rating preparation 25, in which a torque M Soll is input as an operating state rating. The rating preparation 25 derives a corresponding rating supercharging pressure p Soll from the rating torque M 2,Soll , which serves as a control quantity for the regulating unit 23.

[0122] The controlled system (or regulating path, Regelstrecke) 31 comprises the supercharging system 9, which can be adjusted via an adjusting value (control quantity) u, so that an actual supercharging pressure p 2,Ist is output as a regulating quantity. Here, the VTG adjusting mechanism 17 (and / or the wastegate 19) is controlled / adjusted via the adjusting value u. The purpose of the regulating unit 23 is to bring the regulating quantity p 2,IstFollowing (or tracking, i.e., nachzuführen) a pre-given control quantity p 2,Soll Thus, ideally corresponding to the rated boost pressure p 2,Soll Compared with the actual boost pressure p 2,Ist The adjustment deviation (adjustment error) between the two values ​​should be as close to zero as possible. To this end, a regulator 29 is provided, whose output is based on the regulator's adjustment value u. reg In order to facilitate the actual boost pressure p 2, Ist Matched to rated boost pressure p 2, Soll Regulator 29 includes or is configured as a PI regulator.

[0123] To consider the control quantity p 2,Soll To meet the anticipated adjustment value requirement, the regulating unit 23 further includes a pre-control 27. The pre-control 27 outputs an adjustment value u based on the pre-control. vor The adjustment value u is based on the regulator's adjustment value u. reg and the adjustment value u based on pre-control vor Composition. Therefore, the controlled system 9 can follow the rated boost pressure p as quickly as possible. 2,Soll The regulator 29 adjusts the adjustment deviation that can be derived from the model accuracy of the pre-control 27.

[0124] exist Figure 3 The pre-control 27 of the boost pressure regulation 23 is shown in detail. Pre-control 27 takes into account the current primary engine speed n of engine 3. M (Engine speed), ignition timing, and cylinder deactivation. Ignition timing and cylinder deactivation are considered because the increase in enthalpy supplied to turbine 15 is correlated with ignition timing, and the decrease in enthalpy supplied is correlated with cylinder deactivation. These enthalpy changes have an impact on the power output of boost stage 9 and, correspondingly, on the actual boost pressure p that can be generated by boost stage 9. 2,Ist The impact.

[0125] Pre-control 27, based on ignition angle adjustment, considers both the ignition angle change ZW and the time derivative ZW of the ignition angle change. grad Using characteristic curve 45, the engine speed n M and ignition angle change ZW grad The time derivative can determine the ignition angle adjustment value u. ZW The dynamic part u ZW,dyn Here, the time derivative ZW of the ignition angle change... grad The curve resembles a bell curve. The absolute part u ZW,abs It can be determined by varying the ignition angle ZW and the characteristic curve 47. The absolute and dynamic parts u... ZW,abs , u ZW,dyn Multiply them together to obtain the ignition angle adjustment value u.ZW , with consideration of the above-mentioned enthalpy change and the supercharging stage 9 can be adjusted accordingly in order to compensate for the enthalpy change.

[0126] Furthermore, the number of cylinders to be suppressed ZAS and the time derivative of the cylinder suppression ZAS grad is considered by the cylinder suppression adjustment value u ZAS . The cylinder suppression adjustment value u ZAS,abs consists of an absolute part u ZAS,dyn and a dynamic part u ZAS,abs . The absolute part u M can be determined by a characteristic curve 51 in the case of knowledge of the number of cylinders to be suppressed ZAS and the engine speed n ZAS,dyn . The dynamic part u grad can be determined by the time derivative of the cylinder suppression ZAS M , the engine speed n grad and a characteristic curve 53. The curve of the time derivative of the cylinder suppression ZAS ZAS is similar to a bell curve. The cylinder suppression adjustment value u ZAS,abs is derived from the sum of its parts u ZAS,dyn , u ZAS . Finally, the cylinder suppression adjustment value u ZAS,abs is determined in such a way that its absolute and dynamic parts u ZAS,dyn , u ZAS are added. The cylinder suppression adjustment value u ZW is then loaded, for example multiplied, with a scaling factor EF, wherein the scaling factor can be determined by a characteristic curve 49 in the case of knowledge of the number of cylinders to be suppressed ZAS. Here, the scaling factor EF is a proportionality factor with respect to the number of cylinders. Thus, in the case of full suppression, i.e. when all cylinders are suppressed, the enthalpy provided at the turbine 15 is substantially no longer present. In the case of partial suppression, the enthalpy provision depends on the cylinders which are also (not suppressed) combusted. By means of the scaling factor EF, the enthalpy provision is taken into account depending on the number of suppressed cylinders ZAS.

[0127] Depending on the operating point of the engine 3, the torque reduction is achieved by means of the ignition angle adjustment in the retardation direction or by means of the cylinder suppression. This means that the torque reduction is either achieved by means of the ignition angle adjustment in the retardation direction or by means of the cylinder suppression. The selection is implemented in the module 48.

[0128] When there is no ignition angle adjustment, the ignition angle adjustment adjustment value u ZW is input as a zero value in the module 48. Accordingly, as an output quantity from the module 48 (the scaling factor EF to be processed at the input side of the module 48), it is known which is then acted on the cylinder suppression adjustment value u ZAS . Accordingly, the scaled cylinder suppression adjustment value u zasas dynamic precontrol-based adjustment value u vor,dyn as input quantity to the switch 59.

[0129] If the torque reduction is achieved via the ignition angle adjustment, the corresponding ignition angle adjustment adjustment value u ZW is input at the input side at the module 48. ZAS The cylinder deactivation adjustment value u ZW corresponds to zero and the scaling factor EF does not act or has no influence, since it only acts in the case of cylinder deactivation. Thus, the ignition angle adjustment adjustment value u ZAS is added by the module 48, which corresponds to zero, and then input to the switch 59. Thus, the dynamic precontrol-based adjustment value u vor,dyn corresponds to the ignition angle adjustment adjustment value u ZW .

[0130] Thus, the switch 59 as input quantity contains the dynamic precontrol-based adjustment value u vor,dyn , with which a highly dynamic process in the boost pressure regulation, that is to say the ignition angle adjustment and the cylinder deactivation, can be shown. The dynamic precontrol-based adjustment value u vor,dyn corresponds to either the ignition angle adjustment adjustment value u ZW or the cylinder deactivation adjustment value u ZAS .

[0131] The switch 59 as further input quantity has an offset-based adjustment value u off for the ATL 9. Via the module 57, between the dynamic precontrol-based adjustment value u vor,dyn and the offset-based adjustment value u off can be adjusted as output quantity of the switch 59. Here, the module 57 can be an application function, that is to say the user can define the switching conditions for the switch 59 himself.

[0132] Switch 65 receives the output of switch 59. Furthermore, switch 65 has a zero value as an input quantity, which is shown as module 61. This zero value corresponds to the orientation of the regulating mechanism 17 and / or the exhaust valve 19, where the compression power of the supercharging system 9 is minimized. In other words, the VTG is adjusted such that the exhaust-induced drive power of the turbine 15 is minimized. Alternatively / supplementarily, the exhaust valve 19 is opened to such an extent that as much exhaust gas as possible is directed around the turbine 15. Alternatively, an adjustment value can be selected from module 61 as an alternative to the zero value to maximize the compression power of the supercharging system 9. When module 63 acquires a shift in the transmission, a corresponding shift acquisition signal is directed to switch 65, thereby deriving the output of switch 59 as the output of switch 65. If no shift acquisition signal is available, the quantity provided by module 61 is the output of switch 59.

[0133] If the switching process is detected, module 63 sends the corresponding switching process detection signal to switch 65, causing switch 61 to output the previous output of switch 59, i.e., a dynamic adjustment value u based on pre-control. vor,dyn Or an adjustment value u based on the deviation value off The output of switch 65 is used as the adjustment value u based on pre-control. vor The pressure is supplied to the booster regulator 23. In an alternative not shown, the pre-control 27 can be configured without the switch 59 and module 57. In this alternative, the switch 65 can correspondingly have only and correspondingly output or transmit a dynamic pre-control-based adjustment value u on the input side. vor,dyn off Or an adjustment value from module 61.

[0134] Additionally, module 67 can determine the adjustment value u for the adjustment components using the fundamental equations of the turbocharger. vor,stat This can be added to the output of switch 65. Therefore, based on the pre-control adjustment value u vor Additionally, the fundamental equations for turbochargers can be considered.

[0135] exist Figure 4a In the context of the gear shifting process of transmission 10, the rated and actual boost pressure p are... 2,Soll ,p 2,Ist The curve is plotted over time, where cylinder suppression is achieved during the shift process and boost pressure regulation 23 is implemented without pre-control 27. The actual boost pressure p can be identified. 2,Ist The pressure increase p is relatively obvious after the rated boost pressure. 2,Soll .

[0136] If, in contrast, a pre-control 27 is taken into account for such a gear shift process, it follows for the nominal and actual boost pressures p 2,Soll,vor , p 2,Ist,vor that the curve, recognizable from which, the actual boost pressure p 2,Ist,vor follows the nominal boost pressure p 2,Soll,vor relatively better.

[0137] Figure 4b The above-mentioned curves for the gear shift process are shown for p 2,Soll , p 2,Ist and p 2,Soll,vor , p 2,Ist,vor , in which the ignition angle adjustment is implemented. It is also recognizable here that the actual boost pressure p 2,Ist,vor follows the nominal boost pressure p 2,Soll,vor relatively better in the case of the pre-control 27.

[0138] The curve pairs p 2,Soll , p 2,Ist and p 2,Soll,vor , p 2,Ist,vor are depicted only for better illustrability at different pressure levels.

Claims

1. A method for operating a turbocharging system for an internal combustion engine during a gear shift in a transmission coupled to an internal combustion engine by means of boost pressure regulation, wherein, The booster system has a booster stage with a compressor and a driver, and the method includes: - Obtain the rated quantity of operating status (M) Moment That is, the torque to be generated by the internal combustion engine; - The rated boost pressure is derived from the rated operating conditions; - The boost pressure system is adjusted by means of the boost pressure regulation to achieve the rated boost pressure. The boost pressure regulation includes the following pre-control, which takes into account the rated amount (M) for achieving the operating state. Moment ) Ignition angle adjustment and / or cylinder suppression, The adjustment of the booster system is achieved via an adjustment component. The method further includes: - Determine the ignition angle adjustment value for the adjustment component; and - Determine the cylinder suppression adjustment value for the adjustment component. The determination of the ignition angle adjustment value further includes: - Obtain the ignition angle adjustment value; - Determine the absolute portion of the ignition angle adjustment value using the ignition angle adjustment value; and - The dynamic portion of the ignition angle adjustment value is determined by the time variation of the ignition angle adjustment. Furthermore, the determination of the cylinder suppression adjustment value also includes: - Obtain the number of cylinders to be suppressed; - The absolute portion of the cylinder suppression adjustment value is determined by the number of cylinders to be suppressed; and - The dynamic portion of the cylinder suppression adjustment value is determined by the time variation of the cylinder suppression.

2. The method according to claim 1, characterized in that, The ignition angle adjustment value is determined by multiplying its absolute part and dynamic part together.

3. The method according to claim 1 or 2, characterized in that, The cylinder suppression adjustment value is determined by adding its absolute part and dynamic part.

4. The method according to claim 1 or 2, characterized in that, The determination of the ignition angle adjustment value and the cylinder suppression adjustment value are achieved by means of characteristic lines and / or families of characteristic lines.

5. The method according to claim 4, characterized in that, The dynamic portion of the ignition angle adjustment value and the absolute and dynamic portions of the cylinder suppression adjustment value can be determined depending on the speed of the internal combustion engine.

6. The method according to claim 1 or 2, further comprising: - The ignition angle adjustment value and the cylinder suppression adjustment value are selected based on the operating point of the internal combustion engine.

7. The method according to claim 1 or 2, further comprising: - Obtain the shifting process of the transmission that is connected to the internal combustion engine.

8. The method according to claim 1 or 2, characterized in that, The pre-control also takes into account the fundamental equations of the turbocharger.

9. The method according to claim 1, characterized in that, The adjustment component is an exhaust bypass valve or a VTG control unit.

10. A control unit for a turbocharging system of an internal combustion engine, characterized in that, The control unit is configured to implement the method according to any one of the preceding claims.

11. An internal combustion engine having a supercharging system, the supercharging system having a supercharging stage, wherein the supercharging stage has a compressor and a driver, and has a control unit according to claim 10.

12. A motor vehicle equipped with an internal combustion engine according to claim 11.

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