"Method for operating a charging system"

Abstract

The invention relates to a method for operating a charging system for an internal combustion engine by means of a boost pressure control system during a shifting operation of a transmission operatively connected to the internal combustion engine, wherein the charging system comprises a charging stage with a compressor and a drive. A target operating condition, in particular a torque to be generated by the internal combustion engine, is detected. A target boost pressure is derived from the target operating condition. The charging system is adjusted to achieve the target boost pressure by means of the boost pressure control system, wherein the boost pressure control system includes a feedforward control that takes into account ignition timing adjustment and / or cylinder deactivation to achieve the target operating condition.Furthermore, a control system for a charging system for an internal combustion engine, an internal combustion engine with a charging system, and a motor vehicle with an internal combustion engine are described.

Description

[0001] The invention relates to a method for operating a charging system for an internal combustion engine by means of a boost pressure control, a control for a charging system for an internal combustion engine, an internal combustion engine with a charging system and a motor vehicle with an internal combustion engine.

[0002] Generally, charging systems for internal combustion engines, especially in the motor vehicle sector, are known to supply the cylinders of the internal combustion engine with pressurized air for the combustion of fuel.

[0003] Turbochargers and compressors are examples of devices used to provide air under pressure. Turbochargers have a compressor and can be equipped with their own drive for the compressor, such as an electric motor, or they can be driven, for example, by the exhaust gas from an internal combustion engine, in which case the exhaust gas drives a turbine that is operatively connected / coupled to the compressor via a shaft. The latter are also called exhaust gas turbochargers.

[0004] During highly dynamic shifting processes of manual transmissions, and especially automatic transmissions, the operating point of the internal combustion engine and, accordingly, that of the turbocharger changes abruptly.

[0005] It is known to make a gear shifting process more convenient by reducing the torque generated by the internal combustion engine, while the drive and internal combustion engine are decoupled from each other by a clutch and the transmission changes the torque ratio, i.e., changes gear.

[0006] The torque can be reduced, for example, by deactivating cylinders, which reduces the enthalpy (of the exhaust gas) at the turbocharger turbine, causing it to reduce boost pressure. The connection of the combustion engine to the transmission after the torque reduction is delayed due to the turbocharger's inertia. Currently, there is no dynamic correction in the control system at this point.

[0007] Furthermore, there are approaches where the torque reduction implemented for the shifting process, such as upshifting, is not achieved via the cylinder deactivation described above. For example, this torque reduction can also be achieved by retarding the ignition timing. However, this abruptly increases the enthalpy (of the exhaust gas) at the turbocharger turbine, causing a sharp rise in boost pressure, potentially leading to overshoot. The enthalpy increases because retarding the ignition timing raises the temperature of the exhaust gas expelled from the cylinder. This is because the combustion of the gas mixture in the cylinder is no longer optimal, and the engine efficiency is reduced. This is due to the fact that the combustion of the gas mixture is "delayed" by the ignition timing intervention and thus shifts into the exhaust stroke of the charge exchange.This results in very hot exhaust gas being directed into the exhaust tract during the exhaust stroke, and the expansion of the combustion mixture no longer supports the downward movement of the piston. The later the ignition timing, the more the combustion is shifted into the exhaust stroke.

[0008] Especially at the mechanical and thermal component boundaries of the exhaust gas turbocharger, these enthalpy changes lead to undesirable operating conditions of the internal combustion engine. Particularly in gasoline engines that are (air) quality controlled, these enthalpy changes result in boost pressure overshoots and undershoots, which can influence torque. This dynamic process cannot be satisfactorily compensated for by current feedforward control structures.

[0009] For example, DE 42 14 648 A1 discloses that a lambda control system incorporates a feedforward control mechanism to react quickly enough to sudden changes in operating conditions. Furthermore, DE 41 07 693 A1 describes a system for regulating and controlling a turbocharger of an internal combustion engine, in which a feedforward control mechanism detects a sudden drop in a load signal and outputs a corresponding signal to close a wastegate in order to maintain boost pressure. A feedforward control mechanism from DE 10 2009 032 372 A1 determines a target position of an actuator, based on the turbocharger equation, to determine a boost pressure at the outlet of a compressor of an exhaust gas turbocharger. The turbocharger equation, being a steady-state equation, does not take into account the inertia of the turbocharger. The equation is calculated using physical model values, which, however, do not accurately represent the highly dynamic processes.

[0010] DE 10 2007 060 216 A1 relates to a method for operating a spark-ignition internal combustion engine with a manually operated transmission, in which the torque delivered by the internal combustion engine can be influenced by at least one control variable. An impending shift of the transmission and / or another operating situation of the internal combustion engine, during which a temporary reduction in the torque delivered by the internal combustion engine is necessary and / or desired, is detected, and the torque is reduced depending on the detection by changing at least one control variable of a fuel path. DE 195 19 381 A1 relates to a device that reduces boost pressure depending on a predetermined target engine torque, if the target engine torque or a related target operating variable of the engine is smaller than a corresponding operating variable of the engine without intervention in the boost pressure.

[0011] The object of the present invention is to provide a method that at least partially overcomes the aforementioned disadvantages. Among other things, a feedforward control system should take into account the highly dynamic processes described above during gear shifting.

[0012] This problem is solved by a method according to claim 1, by a control system according to claim 11, by an internal combustion engine according to claim 12 and by a motor vehicle according to claim 13.

[0013] Further advantageous embodiments of the invention will become apparent from the dependent claims and the following description of preferred embodiments of the present invention.

[0014] According to a first aspect, the present invention provides a method for operating a charging system for an internal combustion engine by means of a boost pressure control during a shifting operation of a transmission operatively connected to the internal combustion engine, wherein the charging system comprises a charging stage with a compressor and a drive. The method includes: - Determining a target operating condition value, in particular a torque to be generated by the internal combustion engine; - Deriving a target boost pressure from the operating state target value; - Adjusting the charging system to achieve the target boost pressure by means of boost pressure control, wherein the boost pressure control includes a pilot control that takes into account ignition timing adjustment and / or cylinder deactivation to achieve the target operating state value.

[0015] Here, "shifting process" refers to the shifting process of the manual transmission as described above. The manual transmission, together with the internal combustion engine, is arranged in the drivetrain of a motor vehicle and is designed to translate the engine's speed / torque into the engine's speed / torque. The manual transmission can be designed as an "automatic transmission" in which, among other things, starting, selecting gear ratios and gear stages, and shifting between gear stages are performed automatically by the transmission (and its control unit). The internal combustion engine (engine) can, for example, be a gasoline engine.

[0016] The charging system may in particular include an exhaust gas turbocharger with variable turbine geometry (VTG) and / or with a wastegate (with at least one bypass valve).

[0017] When shifting gears in (automatic) transmissions, a clutch (from the internal combustion engine, specifically its output shaft) is opened, the transmission is disconnected from the engine, and the torque generated by the engine is reduced. The acquisition of an operating state target value captures precisely this comparatively lower target torque of the engine. Additionally or alternatively, operating state target values ​​of the engine can also be acquired, from which the engine's torque can be derived.

[0018] To achieve the engine's target operating parameters, particularly the target torque, a target boost pressure is derived. A turbocharging system, controlled by a boost pressure regulator, is used to provide this target boost pressure. The boost pressure regulator controls the turbocharging system according to the target boost pressure, which serves as the reference value.

[0019] In the context of this invention, the terms control, adjustment, actuation, steering, regulation include both controls in the strict sense (without feedback) and regulations (with one or more control loops).

[0020] Boost pressure control includes a feedforward control system that incorporates, among other things, ignition timing adjustment and / or cylinder deactivation, which are necessary to achieve the target operating state. Ignition timing adjustment refers to a change in the ignition point. Ignition timing adjustment and cylinder deactivation are significant for boost pressure control because they cause a change in enthalpy upstream of the turbine, for example, by increasing the exhaust gas temperature and / or decreasing the exhaust gas volume. This, in turn, affects the turbine (drive) power and thus also the compressor that generates the boost pressure. As described above, this can lead to an (excessive) drop or build-up of boost pressure.Through feedforward control, the control behavior of the boost pressure control can be improved by taking into account the control variable requirement expected from an operating state target value profile and / or a target boost pressure profile.

[0021] According to the invention, the charging system is adjusted via an actuator. For example, the actuator can be a wastegate (valve) or, if the charging system includes an exhaust gas turbocharger with variable turbine geometry (VTG), a VTG control unit. The turbine (drive) power can be adjusted via the actuator by using the wastegate to direct exhaust gas flowing from the combustion chamber around the turbine or by using the VTG control unit to adjust the position of the turbine guide vanes. Since the compressor power depends, among other things, on the turbine (drive) power, the boost pressure can be influenced by adjusting the actuator, particularly to achieve the target boost pressure.

[0022] According to the invention, an ignition timing adjustment control value (control variable) and a cylinder deactivation control value are determined for the actuator. The actuator, i.e., the VTG control and / or the wastegate, can then be adjusted accordingly using the determined control values. In other words, the actuator can be adjusted depending on the ignition timing adjustment and the cylinder deactivation.

[0023] In further details, determining an ignition timing adjustment setpoint can also include the following: - Recording an ignition timing adjustment value; - Determining an absolute proportion of the ignition timing advance value using the ignition timing advance value; and - Determining a dynamic component of the ignition timing adjustment control value from a temporal change in the ignition timing adjustment.

[0024] During gear changes, the engine's torque is reduced while the clutch is disengaged. This torque reduction can be achieved by adjusting the ignition timing. The ignition timing is retarded, meaning the ignition point is advanced (relative to the crankshaft angle). Measuring the ignition timing advance value (the change in the ignition angle) therefore determines the value, or by how many degrees, the ignition timing / angle is changed / adjusted, particularly towards retarded. The torque reduction depends, at least partially, on the ignition timing advance value. Similarly, an increase in the enthalpy output to the turbine depends, at least partially, on the ignition timing advance value. This increase in enthalpy output is related to an increase in exhaust gas temperature resulting from the retarded ignition timing.

[0025] To account for the boost pressure increase resulting from retarding the ignition timing in the pilot control, an absolute and dynamic component of the ignition timing adjustment value is determined. The enthalpy change does not occur instantaneously, but is subject to a delay, due in part to the distance between the cylinder exhaust ports and the turbocharger turbine. The ignition timing adjustment can also be performed in stages; that is, the (complete) adjustment of the ignition timing from an initial to a final value for a cylinder does not occur from one cylinder cycle to the next, but over several cycles, so that the desired ignition timing (final value) is reached no later than the moment the clutch is (re)engaged to the engine. In other words, the ignition timing is retarded in stages after each charge cycle in the cylinder, so that each cylinder fires later than the previous one.As a result, a continuous reduction in torque can be achieved. In particular, the ignition timing adjustment can be implemented such that the graphical representation of the time derivative of the ignition timing adjustment resembles a bell curve. Through the absolute and dynamic components of the control value, the feedforward control can account for the delay in the enthalpy change, at least partially, and adjust the control arrangement accordingly.

[0026] Alternatively, determining the cylinder suppression setting can also include: - Determining the number of cylinders to be hidden; - Determining an absolute proportion of the cylinder deactivation setpoint from the number of cylinders to be deactivated; and - Determining a dynamic component of the cylinder suppression setpoint from a temporal change in cylinder suppression.

[0027] A reduction in the enthalpy supply to the turbine depends, at least partially, on the number of cylinders deactivated. To account for the resulting reduction in boost pressure using feedforward control, an absolute and a dynamic component of the cylinder deactivation control value are determined. Such an enthalpy change resulting from cylinder deactivation does not occur instantaneously, but is also subject to the aforementioned delay. Furthermore, cylinder deactivation can be implemented in such a way that a graphical representation of the time derivative of the cylinder deactivation (or the cylinder deactivation process) resembles a bell curve. Through the absolute and dynamic components of the control value, the feedforward control can account for the delay in the enthalpy reduction, at least partially, and adjust the actuator accordingly.

[0028] In other methods, the ignition timing angle adjustment setpoint can be determined by multiplying its absolute and dynamic components together.

[0029] Furthermore, the cylinder suppression setting can be determined by summing (adding up) its absolute and dynamic components.

[0030] In further implementations, the ignition timing adjustment setting and the cylinder deactivation setting can be determined using characteristic curves and / or maps. These setting values ​​can be stored in the characteristic curves and maps as a function of the current engine speed, the current engine torque, the time derivative of the ignition timing adjustment, the time derivative of the cylinder deactivation, the ignition timing adjustment value, and / or the number of cylinders to be deactivated.

[0031] Furthermore, the dynamic component of the ignition timing adjustment control value, as well as the absolute and dynamic component of the cylinder deactivation control value, can be determined as a function of the internal combustion engine's rotational speed. In particular, the characteristic curves / maps mentioned above can be used for this purpose.

[0032] In further versions, the ignition timing adjustment setting value and the cylinder deactivation setting value can be selected / determined depending on an operating point of the internal combustion engine.

[0033] Furthermore, the shifting process of the transmission (automatic transmission) connected to the internal combustion engine can be detected. A shift detection signal can then be generated from this. This ensures that the boost pressure control only considers the control values ​​resulting from the feedforward control when shifting gears, i.e., when the transmission shift has been detected or the shift detection signal is present.

[0034] Alternatively, the feedforward control can also take the turbocharger's main equation into account. In particular, the feedforward control can determine a control value for the actuator based on the turbocharger's main equation. This control value can be combined with, and especially added to, the ignition timing control value or the cylinder deactivation control value.

[0035] The main equation for turbochargers is as follows: πV=p2p1=[1+m˙Tm˙V⋅ηT⋅ηV⋅ηm⋅T3T1⋅c3c1⋅(1−(p4p3)κ3−1κ3)]κ1κ1−1

[0036] where π V The compressor boost pressure ratio, p1 the pressure upstream of the compressor, p2 the pressure downstream of the compressor (boost pressure), p3 the pressure upstream of the turbine, p4 the pressure downstream of the turbine, T1 the temperature upstream of the compressor, T3 the temperature upstream of the turbine, ṁ T the (exhaust gas) mass flow through the turbine,ṁ v the (combustion) air mass flow through the compressor, η T the isentropic efficiency of the turbine, η V the isentropic efficiency of the compressor, η m the mechanical efficiency, c3 the specific heat capacity of the exhaust gas, c1 the specific heat capacity of the combustion air, κ3 the isentropic index of the exhaust gas and κ1 the isentropic index of the combustion air.

[0037] To determine the values ​​for the specific heat capacities c1, c3 and the isentropic exponents κ1, κ3, models can be used that provide the values ​​depending on the gas composition at the turbine and the compressor. The efficiencies η can also be determined. T , η V and η m The pressure upstream and downstream of turbine p3, p4 can be determined at least indirectly, if not directly, using appropriate pressure sensors and / or models.

[0038] Furthermore, the following equation for the target turbine mass flow rate results from the main equation of the turbocharger: m˙T,Sollp1=m˙V⋅c1⋅T1⋅1ηV⋅((p2,Sollp1)κ1κ1−1−1)c1⋅T3⋅ηT⋅ηM⋅(1−(p4p3)κ3−1κ3)

[0039] The control value for the actuator arrangement can be derived from the target turbine mass flow rate as a function of the turbocharger main equation, which allows the boost pressure to be influenced, especially to achieve the target boost pressure.

[0040] By additionally taking the turbocharger's main equation into account with the feedforward control, the boost pressure control can be at least partially relieved and / or its control behavior can be further improved.

[0041] According to a second aspect, the present invention provides a control system for a charging system for an internal combustion engine, wherein the control system is configured to carry out the method according to the first aspect.

[0042] According to a third aspect, the present invention provides an internal combustion engine with a charging system comprising a charging stage, wherein the charging stage includes a compressor and a drive, and with a control system according to the second aspect.

[0043] According to a fourth aspect, the present invention provides a motor vehicle with an internal combustion engine according to the third aspect.

[0044] Exemplary embodiments of the invention will now be described by way of example and with reference to the accompanying drawing. This shows: Fig. 1 schematically an embodiment of a motor vehicle with an internal combustion engine; Fig. 2 a schematic representation of a boost pressure control for the internal combustion engine according to the method according to the invention; Fig. 3 a feedforward control of the boost pressure control according to the inventive method; and Fig. 4a Schematic diagrams of target and actual boost pressure curves without and with the influence of boost pressure control during a gear change with cylinder deactivation; and Fig. 4b schematic diagrams of target and actual boost pressure curves without and with influence of boost pressure control during a switching process with ignition timing adjustment.

[0045] The Fig. Figure 1 schematically shows a motor vehicle 1 comprising an engine 3, a charging system 9, a clutch 6, and a transmission 10, in particular an automatic transmission. The present invention is not limited to a specific type of engine. It can be an internal combustion engine, which, for example, can be designed as a gasoline engine.

[0046] A control unit 21, which may be configured as an engine control unit, is set up, in particular programmed to control the execution of one of the methods presented in the present disclosure. For this purpose, the control unit 21 is further configured to control the components required for the execution.

[0047] The engine 3 comprises one or more cylinders 4, one of which is shown here. The cylinders 4 are supplied with supercharged (combustion) air by the charging system 9.

[0048] A torque generated by the motor 3, in particular a clutch torque, can be selectively transmitted via the clutch 6 to the gearbox 20 via a crankshaft 2 of the motor and a transmission shaft 8 of the gearbox 10. The gearbox 10 is configured to transmit the torque of the motor 2 transmitted via the clutch 6 to an output shaft 12 of the gearbox 10 with the desired gear ratios.

[0049] The charging system 9 comprises a charging stage 11, which includes 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 is adjustable via an adjustment mechanism 17. In the illustrated embodiment, the charging system 9 is an exhaust gas turbocharger.

[0050] Turbine 15 is supplied with exhaust gas from engine 3 and thus driven by it. Alternatively / in addition to the VTG, a wastegate 19 is provided. Furthermore, a multi-stage turbocharged unit can also be provided. In other words, the turbocharging system 9 can have several turbocharging stages 11. The exhaust gas supplied to turbine 15 and, accordingly, the output of the compressor 13 can be adjusted via the adjustment mechanism 17 (and / or via the wastegate 19).

[0051] The Fig. Figure 2 shows a boost pressure control 23, which is used to operate the engine 3 and in particular its charging system 9.

[0052] The control loop 23 includes a setpoint preparation 25, in which a torque M to be generated by the motor 3 is soıı is entered as an operating state target variable. The setpoint processing 25 derives from the target torque M Soll a corresponding target boost pressure P 2,Soll ab, which serves as the guide parameter for Regulation 23.

[0053] A control loop 31 includes the charging system 9, which is adjustable via a control value (manipulated variable) u, so that an actual boost pressure p 2,Ist The controlled variable is output as a control variable. The VTG adjustment mechanism 17 (and / or the wastegate 19) is controlled / adjusted via the actuator value u. The aim of the control system 23 is to adjust the controlled variable p. 2,Ist the specified reference variable P 2,Soll to adjust so that ideally a control deviation (control difference) which corresponds to a difference between the target boost pressure P 2,Soll and the actual boost pressure p 2,Ist This corresponds to being as close to zero as possible. A controller 29 is provided for this purpose, which provides a controller-based setpoint u. reg outputs to display the actual boost pressure p 2,Ist to the target boost pressure p 2, Soll to adapt. The controller 29 includes a PL controller or is designed as a PL controller.

[0054] To select one from the control variable P 2,SollTo take into account the expected actuator requirement, regulation 23 also includes a feedforward control 27. The feedforward control 27 provides a feedforward-based actuator u vor The control value u is composed of the controller-based control value u. reg and the input-based control value u vor together. This allows the control loop 9 to reach the target boost pressure p as quickly as possible. 2,Soll are tracked while the controller 29 compensates for the control deviation, which may result, among other things, from a model inaccuracy of the feedforward control 27.

[0055] In the Fig. Figure 3 shows the feedforward control 27 of the boost pressure control 23 in detail. The feedforward control 27 takes into account a currently prevailing engine speed n. MThe engine speed (engine 3), ignition timing adjustment, and cylinder deactivation are all taken into account. Ignition timing adjustment and cylinder deactivation are considered because an increase in the enthalpy supply to turbine 15 is dependent on the ignition timing adjustment, and a decrease in the enthalpy supply is dependent on cylinder deactivation. These enthalpy changes influence the performance of boosting stage 9 and, consequently, the actual boost pressure p that can be generated by boosting stage 9. 2,Ist .

[0056] The feedforward control 27 takes into account, from the ignition timing adjustment, both the ignition timing change ZW and a time derivative of the ignition timing change ZW. grad Using a characteristic map 45, the engine speed n can be determined. M and the temporal derivative of the ignition angle change ZW grad a dynamic component u ZW,dyn of an ignition timing adjustment setpoint u ZWDeterminable. The course of the time derivative of the ignition timing change ZW is similar. grad a bell curve. An absolute proportion u ZW,abs is determined by the ignition timing change ZW and a characteristic curve 47. The absolute and dynamic components u ZW,abs , u ZW,dyn are multiplied together and yield the ignition timing adjustment setpoint u ZW , which takes into account the aforementioned enthalpy change and allows the charging stage 9 to be adjusted accordingly to compensate for this enthalpy change.

[0057] Furthermore, the cylinder deactivation determines the number of cylinders to be deactivated (ZAS) and the time derivative of the cylinder deactivation (ZAS). grad taken into account. A cylinder suppression setting u ZAS also includes an absolute proportion u ZAS,abs and a dynamic component ZAS,dyn The absolute proportion u ZAS,absis from a characteristic map 51, knowing the number of cylinders to be hidden (ZAS) and the engine speed (n). M Determinable. The dynamic component u ZAS,dyn is through the temporal derivative of the cylinder suppression ZAS grad , the engine speed n M and a characteristic map 53 can be determined. A progression of the temporal derivative of the cylinder deactivation ZAS. grad resembles a bell curve. The cylinder suppression setting u ZAS The sum of its shares yields u ZAS,abs , u ZAS,dyn Finally, the cylinder suppression setting u ZAS determined by its absolute and dynamic share u ZAS,abs , u ZAS,dyn to be summed up. The cylinder suppression setting u ZASThe value is then multiplied by a scaling factor EF (e.g., by multiplication), which can be determined from a characteristic map 49 knowing the number of cylinders ZAS to be deactivated. The scaling factor EF is a scaling factor based on the number of cylinders. Thus, with complete deactivation, i.e., when all cylinders are deactivated, the enthalpy supply to turbine 15 is essentially non-existent. With partial deactivation, the enthalpy supply depends on the number of cylinders still (not deactivated) firing. The scaling factor EF takes the enthalpy supply into account as a function of the number of deactivated cylinders ZAS.

[0058] Depending on the operating point of engine 3, torque reduction is achieved either by retarding the ignition timing or by cylinder deactivation. This means that the torque reduction is achieved either by retarding the ignition timing or by cylinder deactivation. This selection is made in block 48.

[0059] If no ignition timing adjustment is present, the ignition timing adjustment control value in block 48 is used. ZW as a zero value. Accordingly, the output variable from block 48 is the (scaling factor EF applied to block 48 on the input side), which is then applied to the cylinder suppression control value u. ZAS This has an effect. Accordingly, a scaled cylinder suppression setpoint u is then entered into switch 59. zas as a dynamic feedforward-based control variable u vor,dyn as an input variable.

[0060] If the torque reduction is achieved via the ignition timing adjustment, the corresponding ignition timing adjustment control value is sent to block 48 on the input side. ZW one. Since no cylinder suppression occurs, the cylinder suppression setting corresponds to u. ZAS A zero value and the scaling factor EF play no role or influence, as it only applies when a cylinder is deactivated. Therefore, the ignition timing adjustment setpoint u is derived from block 48. ZW the cylinder suppression control value corresponding to a zero value u ZAS is added and then fed into switch 59. Thus, the dynamic feedforward-based control value then corresponds to u. vor,dyn the ignition timing adjustment setting value u ZW .

[0061] Thus, a switch 59 receives the dynamic, feedforward-based control value u as its input variable. vor,dyn, with which the highly dynamic processes, i.e., ignition timing adjustment and cylinder deactivation, in boost pressure control can be represented. The dynamic, pre-control-based control value u vor,dyn corresponds either to the ignition timing adjustment setting value u ZW or the cylinder suppression setting u ZAS .

[0062] Switch 59 has an offset-based setpoint as a further input variable u. off for the ATL 9. Block 57 allows switching between the dynamic feedforward-based control value u vor,dyn and the offset-based setpoint u off The output value of switch 59 can be set. Block 57 can represent an application function, meaning a user can define a switching condition for switch 59 themselves.

[0063] Switch 65 receives the output signal from switch 59. Switch 65 also has a zero value as an input signal, represented by block 61. This zero value corresponds to a position of the adjustment mechanism 17 and / or the wastegate 19 in which the compression power of the charging system 9 is at its lowest. In other words, the VTG is set such that the exhaust-induced drive power of the turbine 15 is as low as possible. Alternatively / additionally, the wastegate 19 is opened as far as possible to allow as much exhaust gas as possible to bypass the turbine 15. Alternatively, instead of the zero value, a control value can be selected from block 61 that maximizes the compression power of the charging system 9. When block 63 detects a transmission shift, a corresponding shift detection signal is sent to switch 65, so that an output signal from switch 59 becomes the output signal of switch 65.If no switching process detection signal is present, the quantity provided by block 61 is the output quantity of switch 59.

[0064] When the switching operation is detected, block 63 sends the corresponding switching operation detection signal to switch 65, so that switch 61 outputs the output value of the previous switch 59 as its output value, i.e., the dynamic feedforward-based control value u. vor,dyn or the offset-based setpoint u off The output of switch 65 is defined as a feedforward-based control value u. vor supplied to the boost pressure control 23. In an alternative (not shown), the pilot control 27 can be configured without switch 59 and block 57. In this alternative, switch 65 can accordingly only input the dynamic pilot-controlled actuator u. vor,dyn off or display the setpoint value from block 61 and output or forward it accordingly.

[0065] Additionally, a control value u can be derived from block 67 using the turbocharger main equation. vor,stat for the actuator arrangement, which can be summed to the output variable of switch 65. Thus, the feedforward-based actuator value u can be determined. vor Additionally, the main equation for turbochargers must be taken into account.

[0066] In the Fig. 4a are curves for the target and actual boost pressure p 2,Soll , p 2,Ist The graph shows the following for a shift operation of the transmission 10 over time, whereby cylinder deactivation occurs during the shift operation and the boost pressure control 23 operates without the pilot control 27. It can be seen that the actual boost pressure p 2,Ist comparatively significantly below the target boost pressure p 2,Soll chasing after.

[0067] If, however, the feedforward control 27 is taken into account for such a switching process, the following curves result for the target and actual boost pressure P. 2,Soll,vor , P 2,Ist,vorfrom which it can be seen that the actual boost pressure p 2,Ist,vor the target boost pressure P 2,Soll,vor is comparatively better tracked.

[0068] The Fig. 4b shows the course pairs described above p 2,Soll , p 2,Ist and P 2,Soll,vor , P 2,Ist,vor for a switching process in which an ignition timing adjustment takes place. Here too, it can be seen that, taking into account the feedforward control 27, the actual boost pressure P 2,Ist,vor the target boost pressure P 2,Soll,vor is comparatively better tracked.

[0069] The course pairs p 2,Soll , p 2,Ist and P 2,Soll,vor , P 2,Ist,vor They are simply applied at different print levels for better visualization. Reference symbol list 1 motor vehicle 3 Internal combustion engine (motor) 5 Air duct 7 Exhaust pipe 9 Charging system 10 manual transmissions 11th charging stage 13 compressors 14 wave 15 Turbine 17 VTG adjustment mechanism (actuating arrangement) 19 Wastegate (actuator arrangement) 21 Control 25 Setpoint preparation 27 Feedforward control 29 controllers 31 Positioning arrangement 35 Motor speed detection 37 Detecting an ignition timing adjustment 39 Determining a time derivative of the ignition timing adjustment 41 Determining the number of cylinders being blocked 43 Determining a time derivative of the cylinder suppression 45 characteristic map 47 Characteristic curve 48 blocks 49 Characteristic curve 51 Characteristic map 53 Characteristic curve 57 Switching process detection block 59 switches Block 61 63 Switching process detection block 65 switches EF scaling factor n MEngine speed (internal combustion engine) p 2,Soll Target boost pressure p 2,Ist Actual boost pressure P 2,Soll,vor Target boost pressure taking into account the pilot control p 2,Ist,vor Actual boost pressure taking into account the feedforward control u ZW,abs Ignition timing adjustment value (absolute value) u ZW,dyn Ignition timing adjustment control value (dynamic component) u ZW Ignition timing adjustment setting value u ZAS,abs Cylinder suppression setting (absolute percentage) u ZAS,dyn Cylinder suppression setting (dynamic component) u ZAS Cylinder suppression setting u Position value u reg controller-based setpoint u vor Input-based control value u vor,dyn Input-based control value (dynamic component) u vor,stat Input-based control value (stationary component) ZW ignition timing change ZW grad Time derivative of the ignition angle change ZAS Number of hidden cylinders ZAS grad temporal derivative of cylinder suppression

Claims

[1] Method for operating a charging system (9) for an internal combustion engine (3) by means of a boost pressure control during a shifting operation of a manual transmission (10) operatively connected to the internal combustion engine (3), wherein the charging system (9) comprises a charging stage (11) with a compressor (13) and a drive (15), comprising: - Capturing an operating state target value (M) Moment ), in particular a torque to be generated by the internal combustion engine (3); - Deriving a target boost pressure (p 2,Soll ) from the operating state target value (M Moment ); - Adjusting the charging system (9) to achieve the target boost pressure (p 2,Soll ) by means of the boost pressure control, wherein the adjustment of the charging system (9) is carried out via an actuating arrangement (31), in particular a wastegate valve (19) or a VTG control (17), this is done wherein the boost pressure control includes a pilot control (27) which adjusts the ignition timing and / or deactivates cylinders to achieve the target operating state value (M Moment ) taken into account, the procedure further includes: - Determining an ignition timing adjustment setpoint (u ZW ) for the positioning arrangement (31); and - Determining a cylinder suppression setpoint (u ZAS,abs ) for the positioning arrangement (31). [2] Method according to claim 1, wherein the determination of the ignition timing adjustment setpoint (u ZW ) further includes: - Recording an ignition timing adjustment value (IQ); - Determining an absolute proportion (u ZW,abs ) of the ignition timing adjustment setpoint (u ZW ) by means of the ignition timing adjustment value (IQ); and - Determining a dynamic component u ZW,dyn ) of the ignition timing adjustment setpoint (u ZW) from a change in the ignition timing (Ignition timing) grad ). [3] Method according to claim 1, wherein determining the cylinder suppression setpoint (u ZAS,abs ) further includes: - Determining the number of cylinders to be hidden (ZAS); and - Determining an absolute proportion (u ZAS,abs ) of the cylinder suppression setting (u ZAS ) from the number of cylinders to be hidden (ZAS); and - Determining a dynamic component (u ZAS,dyn ) of the cylinder suppression setting (u ZAS,abs ) from a temporal change in cylinder suppression (ZAS) grad ). [4] Method according to claim 2 or 3, wherein determining the ignition timing adjustment setpoint (u ZW ) is done by determining its absolute and dynamic component (u ZW,abs ; u ZW,dyn ) are multiplied together. [5] Method according to claim 3 or 4, wherein determining the cylinder suppression setpoint (u ZAS,abs ) is done by determining its absolute and dynamic component (u ZAS,abs ; u ZAS,abs,dyn ) are summed up. [6] Method according to any one of claims 1 to 5, wherein the determination of the ignition timing adjustment setpoint (u ZW ) and determining the cylinder suppression setpoint (u ZAS,abs ) using characteristic curves (47, 49) and / or characteristic maps (45, 51, 53). [7] Method according to claim 6, wherein the dynamic component (u ZW,ayn ) of the ignition timing adjustment setpoint (u ZW ) as well as the absolute and dynamic component (u ZAS,abs ; u ZAS,abs,dyn ) of the cylinder suppression setting (u ZAS,abs ) depending on a rotational speed (n M ) of the internal combustion engine (3) can be determined. [8] Method according to any one of claims 1 to 7, further comprising: - Selecting the ignition timing adjustment setting value (u ZW ) and the cylinder suppression setting (u ZAS,abs ) depending on an operating point of the internal combustion engine (3). [9] A method according to any of the preceding claims, further comprising: - Recording the shifting process of the gearbox (10) connected to the internal combustion engine (3). [10] Method according to one of the preceding claims, wherein the feedforward control (27) further takes into account the turbocharger main equation. [11] Control (21) for a charging system (9) for an internal combustion engine (3), wherein the control (21) is configured to perform the method according to one of the preceding claims. [12] Internal combustion engine (3) with a charging system (9) with a charging stage (11), wherein the charging stage (11) comprises a compressor (13) and a drive (15), and with a control (21) according to claim 11. [13] Motor vehicle (1) with an internal combustion engine (3) according to claim 12.

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