Method for determining a maximum position setting value of a turbine of a turbocharger

Abstract

The invention relates to a determination method for determining a final setting value (Cf) of an opening characteristic quantity of a turbine of a turbocharger equipped with an internal combustion engine during a torque rise transient phase of said engine, in which a first setting value (C1) of this characteristic quantity is determined as a function of at least one operating parameter of said engine, characterized in that this first setting value (C1) is compared (54) with a predetermined maximum allowable limit value (Pos_max) of this characteristic quantity, for which value of the operating parameter of said engine, the torque rise of said engine is considered to be optimal, and in that, when said first setting value (C1) is less than said maximum value (Pos_max), said first setting value (C1) is applied as said final setting value (Cf), otherwise said predetermined maximum limit value (Pos_max) is applied as said final setting value (Cf).

Description

Technical Field

[0001] This invention claims priority to French application No. 2010697, filed on October 19, 2020, the contents of which (text, drawings and claims) are incorporated herein by reference.

[0002] This invention relates to the field of control of internal combustion engine turbocharging systems. The objective of this invention is to provide a method for determining the final set value of the turbine opening characteristic quantity of a turbocharger. Background Technology

[0003] The adoption of pollution control standards has guided the automotive industry to continuously optimize internal combustion engine efficiency. The use of turbocharging, combined with engine downsizing, represents a significant step forward in this direction. Today, to further reduce emissions within the context of European €7 regulations, US Sulev 30 regulations, and Chinese China 7 regulations, the adoption of Miller cycle combustion systems combined with turbochargers with variable geometry is gaining traction. These solutions also reduce fuel consumption in vehicles with thermal engines.

[0004] To maximize the torque of a thermal engine, as much air as possible needs to be contained within the combustion chamber while maintaining stable and efficient combustion. In most cases, this filling of the engine with fresh air is achieved primarily by increasing the pressure at the cylinder inlet using a compressor. However, for fresh air to be drawn in, the gases in the combustion chamber must be properly expelled.

[0005] During normal operation, under stable operating conditions, the gradual closing of the turbine actuator allows the intake pressure to increase. In this condition, the cylinder fill increases, and combustion efficiency is maintained because the residual unburned gases remain unchanged or almost unchanged. Therefore, torque increases. This method is known from document US7124582B2.

[0006] However, the more significant closure of the actuator continues to increase the pressure at the exhaust, but this increase now leads to an increase in combustion gases in the combustion chamber, which reduces the amount of fresh air supplied and consequently reduces combustion efficiency. In this case, despite the increased intake pressure, airflow decreases and combustion degrades. Furthermore, the increase in pumping losses is exacerbated because the exhaust pressure increases faster than the intake pressure. The resulting engine torque is thus degraded.

[0007] During the load transient, the principle remains the same, but this time it is dynamic. The closing of the actuator will cause an increase in intake pressure, which is converted into airflow. This increase in air is then consumed by the turbine, which increases the pressure upstream of the turbine.

[0008] However, when the turbine is over-closed, the pressure at the exhaust can cause poor venting of gases trapped in the combustion chamber. This increases the amount of residual combustion gases in the chamber, which may be unexhausted or re-inhaled gases. This leaves less space for trapping fresh air and makes combustion less stable. Therefore, this limits airflow and thus limits torque accretion, analogous to stable operation. Summary of the Invention

[0009] The present invention aims to effectively overcome these shortcomings by providing a determination method for determining a final set value of the opening characteristic quantity of the turbine of a turbocharger equipped in an internal combustion engine during the torque rise transient phase of the engine, wherein a first set value of the characteristic quantity is determined based on at least one operating parameter of the engine, characterized in that the first set value is compared with a predetermined maximum allowable limit value of the characteristic quantity, wherein the maximum allowable limit value is considered to be optimal for the value of the operating parameter of the engine, and wherein when the first set value is less than the maximum value, the first set value is applied as the final set value; otherwise, the predetermined maximum limit value is applied as the final set value.

[0010] Its technical advantage lies in its ability to optimize engine torque during transients by continuously adapting the final set value of the turbine position to the engine operating conditions during the transient phase.

[0011] The following additional functions can be configured individually or in combination:

[0012] According to an embodiment, the operating parameter of the engine is the engine speed, and the predetermined maximum allowable limit value of this characteristic quantity is determined by a mapping that establishes the value based on the engine speed.

[0013] According to an embodiment, in order to determine the maximum allowable value of this feature quantity:

[0014] - Determine the maximum permissible pressure upstream of the turbine.

[0015] - Determine the pressure downstream of the turbine.

[0016] - Determine the exhaust gas flow rate.

[0017] - The expansion ratio is determined based on the ratio of the maximum allowable pressure upstream of the turbine to the pressure downstream of the turbine.

[0018] - Determine a predetermined maximum allowable limit value for the characteristic quantity based on the expansion ratio and the exhaust gas flow rate.

[0019] According to an embodiment, in order to determine the maximum allowable pressure upstream of the turbine:

[0020] - Determine the engine speed.

[0021] - The maximum allowable pressure upstream of the turbine is determined based on a mapping that establishes the pressure according to the engine speed.

[0022] According to a variant of this implementation, the intake pressure is determined, and the maximum permissible pressure upstream of the turbine is determined based on a mapping established according to the engine speed and the intake pressure.

[0023] According to an embodiment, in order to determine the maximum allowable pressure upstream of the turbine:

[0024] - Determine the engine speed.

[0025] - Determine the intake pressure.

[0026] - Determine the initial intake pressure at the start of the transient phase of torque increase in the engine.

[0027] -The intake pressure is dimensionlessly measured from the initial intake pressure.

[0028] - A dimensionless maximum allowable pressure upstream of the turbine is determined based on a mapping established according to the engine speed and the dimensionless intake pressure.

[0029] - The maximum allowable pressure upstream of the turbine is determined by the product of the dimensionless maximum allowable pressure upstream of the turbine and the initial intake pressure.

[0030] According to an embodiment, the engine is equipped with camshaft phase shifters and management components for managing these phase shifters. The method includes at least one specific management mode for managing these phase shifters and, for each specific mode, includes a mapping that establishes a dimensionless maximum permissible pressure upstream of the turbine based on the initial intake pressure. The maximum permissible pressure upstream of the turbine is then selected according to the specific mode.

[0031] According to an embodiment,

[0032] - A first pressure correction value is determined based on a mapping that establishes the first correction value based on the engine speed and camshaft croisement.

[0033] - A second pressure correction value is determined based on a mapping that establishes the second correction value based on the engine speed and camshaft cross position.

[0034] - The maximum permissible pressure upstream of the turbine, obtained by multiplying the dimensionless maximum permissible pressure upstream of the turbine with the initial intake pressure, is corrected by adding these two pressure correction values.

[0035] According to an embodiment, the maximum permissible pressure upstream of the turbine is selected between the maximum permissible pressure upstream of the turbine obtained according to the specific mode and the maximum permissible pressure upstream of the turbine obtained using the pressure correction value.

[0036] According to an embodiment, when the turbocharger is a turbocharger with variable geometry, the opening characteristic of the turbine is the position of the turbine blade actuator; or, when the turbocharger is a turbocharger with fixed geometry, the opening characteristic of the turbine is the position of the turbine unloading valve actuator.

[0037] The present invention also relates to a vehicle equipped with an internal combustion engine supercharged by a turbocharger, characterized in that the vehicle includes a computer, the computer including acquisition and processing components for acquisition and processing via software instructions stored in a memory, and control components required for carrying out the method of the present invention. Attached Figure Description

[0038] Other features and advantages of the invention will become more apparent from the following detailed description and accompanying drawings of non-limiting specific embodiments, in which:

[0039] - Figure 1 The internal combustion engine of the present invention is illustrated schematically.

[0040] - Figure 2 The following parameters are shown over time in several boxes labeled A through F: airflow, intake pressure, turbine upstream pressure, CA50, pumping losses, and engine torque, with the evolution pertaining to four positions of the actuator between 75% and 90% actuator closure.

[0041] - Figure 3 The following parameters are shown over time in several boxes labeled A through F: airflow, intake pressure, turbine upstream pressure, CA50, pumping losses, and engine torque, with the evolution relative to the four intake and exhaust positions of the phase shifter.

[0042] - Figure 4The turbine field is shown, which establishes the maximum position of the blades based on the expansion ratio and exhaust gas flow rate.

[0043] - Figure 5 An embodiment of the method of the present invention is shown.

[0044] - Figure 6 The effect of dimensionless measurement by initial pressure is shown.

[0045] - Figure 7 Another embodiment of the method of the present invention is shown.

[0046] - Figure 8 Another embodiment of the method of the present invention is shown.

[0047] - Figure 9 Another embodiment of the method of the present invention is shown.

[0048] - Figure 10 Another embodiment of the method of the present invention is shown.

[0049] - Figure 11 Another embodiment of the method of the present invention is shown.

[0050] - Figure 12 Another embodiment of the method of the present invention is shown. Detailed Implementation

[0051] Figure 1 An internal combustion engine 1, either controlled ignition or compression ignition, is shown. This engine includes an engine block having at least one cylinder 2 (e.g., four cylinders) for combustion. Such a thermal engine can be fitted to a vehicle (e.g., a motor vehicle) to allow for the movement of the vehicle.

[0052] The intake valves and / or exhaust valves of cylinder 2 are actuated by camshafts, which are themselves connected to actuators called camshaft "phase shifters". These actuators are capable of modifying the angular positioning of the camshaft assembly relative to the crankshaft, and thus modifying the adjustment of the values ​​for the opening and closing times of the intake valves and / or the exhaust valves.

[0053] The thermal engine also includes a computer (not shown) comprising acquisition and processing components for acquiring and processing via software instructions stored in a memory, and control components required for implementing the methods detailed below.

[0054] The heat engine is connected to an air intake line 3, which directs the air required for its operation toward the heat engine 1. The intake line 3 conventionally comprises, according to the direction of air flow in the line, components in the following order:

[0055] -Air inlet E,

[0056] - Air filter 4, this air filter is used to trap dust contained in the intake air.

[0057] - Compressor 5 of turbocharger 13

[0058] - Cooler 6, used to cool compressed air

[0059] - Air metering valve 7, which controls the flow rate of air drawn into engine 1, and is conventionally, for example, a butterfly valve box.

[0060] - Air distributor 8, which is used to distribute air toward the cylinder 2 of the heat engine.

[0061] The heat engine is further connected to an exhaust line 9, which discharges combustion gases generated in the cylinder 2 during engine operation. The exhaust line 9 conventionally comprises, according to the direction of gas flow in the line, components in the following order:

[0062] -Exhaust gas collector 10,

[0063] The turbine 11 of the turbocharger 13 is used for the expansion of the exhaust gas and the drive of the compressor 5. The turbine 11 of the turbocharger 13 and the compressor 5 are connected by a drive shaft 14.

[0064] -At least one decontamination component 12 (e.g., oxidation catalyst, particulate filter),

[0065] -Exhaust gas outlet S.

[0066] The turbocharger 13 can be of a type with variable geometry, which includes movable blades, and the inclination of the stator blades (which guide the introduction of gas into the turbine rotor blades) is, for example, variable and computer-controlled. In this case, the opening characteristic of the turbine 11 can be a value characterizing the position of the blades.

[0067] The turbocharger 13 can also be a turbocharger with fixed geometry, and the turbine may include a wastegate equipped with a computer-controlled solenoid valve capable of adjusting the flow rate and, consequently, the pressure at the turbine inlet 11. In this case, the opening characteristic of the turbine 11 may be a value characterizing the opening of the actuator of the wastegate.

[0068] This invention provides a solution that limits upstream turbine pressure to optimize engine torque during the transient phase of torque rise in the engine. This solution eliminates the need for an upstream turbine pressure sensor and inherently takes into account variations in atmospheric pressure and the initial conditions of the transient. The advantage of this solution lies in its optimization for the operation of turbochargers with variable geometry, while also providing gains in turbocharging systems equipped with turbochargers with fixed geometry.

[0069] The objective of this invention is to establish a constraint on the position setpoint of the actuator of a turbocharger with variable geometry, a constraint that optimizes the torque transients of an internal combustion engine. More specifically, a constraint is established on the upstream pressure setpoint of the turbine, a constraint that maximizes the engine torque during transients. This constraint is subsequently expressed by the inverse turbine model as the position of the turbocharger blades.

[0070] Figure 2 An example of the transient evolution at a fixed cam position on a turbocharger with variable geometry as the actuator closes is shown. It is noted that the optimal torque increase (box F) and airflow increase (box A) are not necessarily when the turbine actuator is most closed. In fact, for a test with 90% closure, the upstream turbine pressure (box C) is much higher than with other closures, thus limiting the intake pressure increase (box B) and increasing pumping losses (box E). Furthermore, excessively significant closure causes combustion degradation (box D), resulting in a smaller torque increase (box F). Figure 2 This demonstrates the high dependence of the torque increase on the upstream turbine pressure, thus indicating that there is a maximum upstream turbine pressure that cannot be exceeded to optimize the engine's dynamic response.

[0071] Figure 3 The effect of the intake camshaft positioning on the engine's dynamic response is illustrated. In fact, the engine's exhaust is related to the opening timing of the exhaust valve (the difference between the pressure in the cylinder and the pressure in the exhaust collector), and the fresh air filling itself is related to the closing timing of the intake valve (intake pressure and cylinder pressure). Another phenomenon occurs: scavenging (the removal of residual gases from the chamber by fresh air), which is related to the time between the simultaneous opening of the intake and exhaust valves (intake open OA and exhaust closed FE). Furthermore, scavenging can become negative when the exhaust pressure is greater than the intake pressure, in which case the hot exhaust gases may return to the chamber or even rise into the intake manifold (referred to as re-intake and backscavenging, respectively). Thus, the engine's dynamic response is highly dependent on the camshaft positioning. Moreover, the acceptable exhaust pressure varies depending on the camshaft positioning.

[0072] Figure 2 and Figure 3 This can be shown as a unit phenomenon for a given speed. In fact, during torque transients, actuator adjustment changes according to load and speed. Camshaft positioning changes according to load; therefore, turbine position must be adapted to camshaft adjustment. This introduces two additional factors, not shown: engine load and engine speed.

[0073] Based on these observations, the retained solution thus lies in setting an upstream turbine pressure setpoint, which is then transformed into an expansion ratio using the downstream turbine pressure, and then into a position via a turbine field that establishes the position of the turbine blades based on the expansion ratio and exhaust gas flow rate.

[0074] [Equation 1]

[0075]

[0076] Figure 4 This turbine field is shown, which establishes the blade position Pact based on the expansion ratio Tdet and the exhaust gas flow rate Qech.

[0077] Figure 5 An embodiment of the setup strategy described above is shown, which is used to set the position of the turbine blades of a turbocharger with variable geometry. In this embodiment, mapping 51 calculates the maximum permissible upstream turbine pressure based on the intake pressure Padm and the engine speed N. Next, the expansion ratio is calculated based on the maximum permissible upstream turbine pressure and the downstream turbine pressure Pav_turb (block 52). Then, another mapping 53 determines the blade position Pos_max based on the exhaust gas flow rate Qech and the expansion ratio Tdet. At block 54, a comparison is performed between a first setpoint C1 (i.e., the position required by the boost regulator) and the value of the maximum permissible position Pos_max determined in the mapping (for which the torque increase of the engine is considered optimal). This comparison establishes a final setpoint Cf: when the first setpoint C1 is less than the maximum limit value Pos_max, the first setpoint C1 is applied as the final setpoint Cf; otherwise, the predetermined maximum limit value Pos_max is applied as the final setpoint Cf.

[0078] Additional testing on the engine bench also demonstrated the need to adapt the turbine upstream pressure to the transient initial intake pressure (referred to as the initial intake pressure). At the onset of the transient (when the initial intake pressure is greater than the average atmospheric pressure), maximizing the turbine upstream pressure to correspond to the initial intake pressure is crucial. Otherwise, excessive actuator closure leads to a degraded torque response.

[0079] Figure 6 The evolution of the allowable pressure Pam_turb_opti upstream of the turbine is shown on the left, based on two initial intake pressures Padm_init, and on the right, when the pressure Pam_turb upstream of the turbine is dimensionless from the initial intake pressure Padm_init.

[0080] Simulation studies at different altitudes also emphasize the concept of initial conditions and the necessity of adjusting the profile of the upstream pressure of the turbine according to altitude. In fact, by taking into account the initial pressure, the necessity of correction by external pressure has also been considered. Indeed, since the pressure considered is located upstream of the valve box, this pressure is directly related to ambient pressure and the natural boost of the turbocharger (the turbine speed is never truly zero; even with the actuator fully open, turbine rotation provides natural boost).

[0081] Figure 7 Another embodiment with limiting logic is shown, which limits the position while taking into account corrections implemented by the initial pressure Padm_init. The initial pressure Padm_init is the intake pressure measured at the beginning of the torque-increase transient phase. Thus, the intake pressure Padm is dimensionlessly dedimensionalized from the initial pressure Padm_init (block 55), and then mapping 51 determines the maximum permissible pressure upstream of the turbine, also dimensionlessly dedimensionalized from the initial intake pressure. This dimensionlessly dedimensionalized pressure is then multiplied by the initial pressure Padm_init (block 56) to provide the maximum permissible pressure Pam_turb_max upstream of the turbine. The expansion ratio Tdet (block 52) and the maximum position Pos_max (block 53) are then determined, which is used to saturate the setpoint (block 54).

[0082] Even if the engine is not equipped with a camshaft phase shifter, the solution described above remains effective. In this case, the calibration of the limiting map used to limit the upstream pressure of the turbine is approximate, and the final position of the blades is also approximate.

[0083] The turbine upstream pressure setpoint can be established in several different ways: either the position of the camshaft is known in advance (e.g., a fixed camshaft), or the camshaft evolves dynamically.

[0084] Multiple implementation variations are available. Figure 8 The variant shown is as simple as possible. This variant involves directly specifying the maximum blade position Pos_max based on the individual engine speed N via a simplified mapping 53a. However, this variant is far from precise and imposes too many restrictions because it does not take into account all the phenomena described above.

[0085] Figure 9 Another implementation variation is shown. This variation is also simplified. In fact, it simply means maximizing the upstream turbine pressure value by specifying the engine speed. In this variation, exhaust flow rate and the downstream turbine pressure, which evolves according to the load, are taken into account. The maximization position will therefore not be constant but evolving. Conversely, this model will be very inaccurate because it does not take into account the initial intake pressure and distribution settings.

[0086] Figure 10 Another implementation variation is shown. In the case where the engine is equipped with a camshaft phase shifter (where the position of the cam cannot be known in advance), this implementation needs to cover all plausible scenarios. This necessitates introducing corrections based on the position of the cam. The retained criteria are the crossover Cr and the crossover position Pos_cr during the cycle. The crossover (the duration during which the intake and exhaust valves are simultaneously open) affects the scavenging quality in the positive case and the mass of gas returning to the intake (backscavenging) at the same crossover moment. The crossover position (i.e., the position related to the top dead center that maximizes the crossover) affects the venting at the same crossover. The created model can thus be written in the following form:

[0087] [Equation 2]

[0088]

[0089] Wherein, ΔP1 is a first pressure correction value downstream of the turbine and is calculated in block 57. This first pressure correction value depends on the crossover (in DV) and engine speed N. ΔP2 is a second pressure correction value downstream of the turbine and is calculated in block 58. This second pressure correction value depends on the crossover position and engine speed during the cycle. The first pressure correction value ΔP1 is obtained based on a mapping established based on engine speed N and camshaft crossover Cr. The second pressure correction value ΔP2 is obtained based on a mapping established based on engine speed N and camshaft crossover position Pos_cr. The maximum permissible pressure upstream of the turbine, obtained in block 56 by multiplying the dimensionless maximum permissible pressure upstream of the turbine with the initial intake pressure, is then corrected by adding these two pressure correction values ​​ΔP1 and ΔP2. This yields the value of the maximum permissible pressure Pam_turb_max upstream of the turbine, which is used to determine the final position setpoint Cf.

[0090] This solution is an average solution that covers all possible scenarios. Therefore, this results in uncertainty in maximizing the permissible pressure upstream of the turbine and thus inaccuracy in the final setpoint value. This solution is therefore not optimal when some life conditions require finer precision. Furthermore, the calibration takes longer than the primary solution because it requires characterization for all possible life conditions.

[0091] Under specific management modes used to control the camshaft, without any specific calibration, the upstream pressure of the turbine is allowed to be excessively low under weak intake pressure, and the turbine actuator is over-opened. The result is insufficient engine torque.

[0092] Figure 11 Another implementation variation is shown. In the case of an engine equipped with a camshaft phaser, it has a specific management mode for managing the camshaft phaser. In this specific mode M1, the trajectory of the phaser is known, thus simplifying the calibration for maximizing the permissible exhaust pressure upstream of the turbine, since the correction performed according to the phaser is no longer useful on this branch. This calibration can thus be isolated from the rest and activated only when the engine is in this mode. The trajectory of the phaser may depend on the intake pressure.

[0093] Figure 11 A new schematic block is shown, which becomes Figure 7 solutions and Figure 10 The combination of variations. In the mapping adapted to a specific mode M1, a ratio of intake pressure to maximum permissible initial intake pressure is added (block 60), which is then transformed into maximizing turbine upstream pressure (block 61), and then a converter is performed that can switch from one regulation to another according to the Boolean value Bc (block 62). This addition enables the implementation of an optimal trade-off.

[0094] This solution maintains an average approach to cover most of the life scenarios and incorporates fine-tuning when needed. While it doesn't save time, it's not significantly faster than other solutions. Figure 10 The variants are more time-consuming because they do not require characterization of other life forms.

[0095] Figure 12 Another implementation variation is shown. In this embodiment, multiple life conditions M1 to Mn and the camshaft position are known. By using a converter (block 63) to select the activated mode, it is possible to combine these specific modes M1 to Mn, the mapping being inherent to each of these modes and establishing a dimensionless maximum allowable pressure upstream of the turbine. This variation thus becomes Figure 7The solution is repeated and becomes the selection implemented by converter 63 to select the maximum permissible pressure Pam_turb_max upstream of the turbine according to the specific mode, which is used to determine the final position setpoint Cf. This solution is thus calibrated more quickly and with the most accurate variation; however, it is less flexible in allocating adjustment variations.

[0096] The present invention can optimize the venting of the cylinder while recovering most of the energy at the turbine, which also optimizes the transient engine torque response.

[0097] Without the ingenious manipulation of this invention, the transient engine torque response degrades. This solution requires no additional sensors (e.g., turbine upstream pressure sensors) and can also be applied to turbines equipped with unloading valves (TGFs). This novel approach is universal and does not differentiate between turbochargers with fixed or variable geometries.

Claims

1. A method for determining a final set value (Cf) of the opening characteristic amount of the turbine (11) of a turbocharger (13) equipped in an internal combustion engine (1) during a torque-increase transient phase of the internal combustion engine (1), wherein: - Determine a first set value (C1) of the opening feature quantity based on at least one operating parameter of the internal combustion engine (1). Its features are, - Compare the first set value (C1) with the predetermined maximum allowable limit value (Pos_max) of the opening feature quantity (54). For the predetermined maximum allowable limit value, it is considered that the torque increase of the internal combustion engine is optimal for the value of the operating parameters of the internal combustion engine. - When the first set value (C1) is less than the predetermined maximum allowable limit value (Pos_max), the first set value (C1) is applied as the final set value (Cf); otherwise, the predetermined maximum allowable limit value (Pos_max) is applied as the final set value (Cf). To determine the pre-determined maximum allowable limit value (Pos_max) for the open feature quantity: - Determine the maximum allowable pressure (Pam_turb_max) upstream of the turbine. - Determine the pressure (Pav_turb) downstream of the turbine. - Determine the exhaust gas flow rate (Qech). - The expansion ratio (Tdet) is determined based on the ratio of the maximum allowable pressure (Pam_turb_max) upstream of the turbine to the pressure (Pav_turb) downstream of the turbine. - Based on the expansion ratio (Tdet) and the exhaust gas flow rate (Qech), determine (53) the pre-determined maximum allowable limit value (Pos_max) of the opening feature quantity. To determine the maximum allowable pressure (Pam_turb_max) upstream of the turbine: - Determine the engine speed (N). - Determine the intake pressure (Padm). - Determine the initial intake pressure (Padm_init) at the beginning of the torque increase transient phase of the internal combustion engine. - The initial intake pressure (Padm_init) is dimensionlessly reduced to the intake pressure (Padm) (55). - Based on the mapping (51a), determine the dimensionless maximum allowable pressure upstream of the turbine, which is derived from the initial intake pressure (Padm_init). The mapping establishes the maximum allowable pressure according to the engine speed (N) and the dimensionless intake pressure (Padm). - The maximum allowable pressure (Pam_turb_max) upstream of the turbine is determined by the product of the dimensionless maximum allowable pressure upstream of the turbine and the initial intake pressure (Padm_init).

2. The determination method according to claim 1, characterized in that, The internal combustion engine is equipped with camshaft phase shifters and management components for managing these camshaft phase shifters. The determination method includes at least one specific management mode (M1) for managing these camshaft phase shifters and includes a mapping for each specific management mode, the mapping establishing a dimensionless maximum allowable pressure upstream of the turbine based on the initial intake pressure, the maximum allowable pressure upstream of the turbine (Pam_turb_max) being selected according to the specific management mode (63).

3. The determination method according to claim 1, characterized in that, - Based on mapping, determine (57) the first pressure correction value ( P1), the mapping establishes the first pressure correction value based on the engine speed (N) and camshaft crossover (Cr). P1), - Based on mapping, determine (58) the second pressure correction value ( P2), the mapping establishes the second pressure correction value based on the engine speed (N) and camshaft cross position (Pos_cr). P2), - By adding these two pressure correction values ​​( P1; P2) to correct (59) the maximum allowable pressure (Pam_turb_max) at the upstream of the turbine obtained by multiplying the dimensionless maximum allowable pressure at the upstream of the turbine with the initial intake pressure (Padm_init).

4. The determination method according to claim 2, characterized in that, - Based on mapping, determine (57) the first pressure correction value ( P1), the mapping establishes the first pressure correction value based on the engine speed (N) and camshaft crossover (Cr). P1), - Based on mapping, determine (58) the second pressure correction value ( P2), the mapping establishes the second pressure correction value based on the engine speed (N) and camshaft cross position (Pos_cr). P2), - By adding these two pressure correction values ​​( P1; P2) to correct (59) the maximum allowable pressure (Pam_turb_max) at the upstream of the turbine, which is obtained by multiplying the dimensionless maximum allowable pressure at the upstream of the turbine with the initial intake pressure (Padm_init). The maximum permissible pressure (Pam_turb_max) upstream of the turbine is selected (62) from the maximum permissible pressure upstream of the turbine obtained according to the specific management mode (M1) and using the first pressure correction value. P1) and the second pressure correction value ( The maximum permissible pressure obtained at upstream of the turbine is P2).

5. The determining method according to any one of the preceding claims, characterized in that, When the turbocharger (13) is a turbocharger with variable geometry, the opening feature of the turbine (11) is the position of the turbine (11) blade actuator; or, when the turbocharger (13) is a turbocharger with fixed geometry, the opening feature of the turbine (11) is the position of the turbine (11) unloading valve actuator.

6. A vehicle equipped with an internal combustion engine (1) supercharged by a turbocharger (13), characterized in that, The vehicle includes a computer, which includes acquisition and processing components for acquiring and processing via software instructions stored in a memory, and control components for implementing the determination method according to any one of the preceding claims.

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