Control method and system for a supercharged spark-ignition internal combustion engine configured to purge the intake air cooler.

Abstract

A method (100) for controlling a supercharged spark-ignition internal combustion engine, comprising a heat exchanger mounted downstream of the compressor of a supercharging system and a control valve mounted between the compressor and the heat exchanger, includes the steps of: estimating the mass (M_water) of liquid water accumulating on the inner wall of the heat exchanger in real time; comparing the estimated mass (M_water) with a threshold (S); and activating a cooler purge by generating oscillations between the nominal flow rate and an increased flow rate of the intake air flowing into the heat exchanger and between the nominal advance angle and a decreased advance angle of the ignition advance angle when the estimated water mass (M_water) is higher than the threshold (S).

Description

Technical Field

[0001] The present invention relates particularly to the field of spark ignition internal combustion engines for motor vehicles, and more specifically to a supercharged internal combustion engine for gasoline, alcohol or LPG, comprising a partial exhaust gas recirculation system in the intake section of the engine.

[0002] More specifically, the present invention also relates to the reduction or purging of condensation in a charge air cooler.

Background Art

[0003] Due to the increasingly strict pollutant emission standards for internal combustion engines such as diesel engines, these engines are generally designed using an exhaust gas recirculation (EGR) system. This EGR system generally comprises a recirculation circuit for a high-pressure duct for collecting exhaust gas upstream of the turbine of a turbocharger, a recirculation circuit for a low-pressure duct for collecting exhaust gas downstream of a pollutant removal device in the exhaust line, and a heat exchanger for cooling the gas present in the low-pressure recirculation circuit and for reintroducing those gases at the inlet of the engine. The low-pressure EGR circuit makes it possible for the burned gases resulting from combustion to be drawn back into the intake section and reintroduced upstream of the supercharger.

[0004] These inert gases make it possible, in particular, to increase the total mass of gas introduced into the combustion chamber in a gasoline engine, thereby reducing the need to depressurize the intake manifold and manage the air load. This limits the pump losses and improves combustion. This leads to a reduction in fuel consumption.

[0005] More specifically, the present invention relates to a gas recirculation system comprising a cold water charge air cooler (W-CAC) located downstream of the compressor of a turbocharger system and upstream of the intake manifold.

[0006] To meet emission standards, internal combustion engines must use a low-temperature, low-pressure gas recirculation circuit. However, low-pressure gas recirculation circuits contain hydrated, previously burned gases. Therefore, when the engine is running at low temperatures, there is a risk of condensation of water present in the gas recirculation system onto the intake air cooler.

[0007] Therefore, using a low-pressure EGR circuit results in the problem of water condensation in the engine intake circuit. This water generally originates from moisture in the outside air entering through the outside air inlet and / or from water vapor contained in the exhaust gas recirculated by the low-pressure EGR circuit.

[0008] Subsequently, this condensed water: - Discharge of liquid water droplets from the upstream side of the compressor, which causes premature wear of the compressor wheels. - For example, water accumulation at low points in the intake circuit, which can lead to corrosion problems in the intake air cooler or EGR cooler. - Freezing in the intake circuit under extreme ambient conditions, either during operation or while the engine is cooling down when stopped. This can lead to the accumulation of ice. When the ambient temperature rises above 0°C, this ice turns into liquid, which can cause corrosion or premature wear of the compressor wheel. This water can also be sucked in by the engine, especially during engine startup, and can damage the engine.

[0009] Furthermore, during the operation phase that promotes water condensation, water vapor contained in the mixture of outside air and EGR gas is prone to condensation in the intake circuit and, in particular, on the surface of the intake air cooler, due to environmental conditions such as high ambient humidity and / or low ambient temperature, or due to engine operation.

[0010] This water can accumulate and deactivate within the cooler, potentially interrupting or extinguishing engine combustion. Naturally, water accumulation in the intake cooler can lead to abrupt release, particularly during sharp increases in the flow rate of the EGR air-fuel mixture drawn into the engine, such as after a full load request when the driver presses the accelerator pedal. This abrupt release of liquid water into the combustion chamber results in combustion quenching, also known as a lack of torque generation or misfire, which, in the long run, can damage the engine or some of its associated components, including the transmission catalyst.

[0011] To avoid this condensation phenomenon, the engine operates through a high-pressure exhaust gas recirculation circuit while waiting for the intake line temperature to reach a threshold that avoids condensation in the intake air cooler.

[0012] Patent Document 1 proposes a solution for estimating the risk of condensation in the intake air cooler in order to control the exhaust gas recirculation system. In the event of water accumulation in the intake air cooler, the EGR valve is closed to wait for favorable conditions to be created for the discharge of the condensed water. However, such a solution is not satisfactory because the EGR valve needs to be closed for a long period of time, which leads to a deterioration in fuel efficiency.

[0013] There is a need to improve the management of liquid water accumulation and removal within the intake circuit, and more specifically, within the intake cooler of a supercharged spark-ignition internal combustion engine. [Prior art documents] [Patent Documents]

[0014] [Patent Document 1] French Patent No. 3064678 [Overview of the Initiative]

[0015] Therefore, the object of the present invention is to provide an engine control method and system configured to manage the accumulation and removal of liquid water in an intake air cooler.

[0016] The object of the present invention is a method for controlling a spark-ignition internal combustion engine comprising at least one cylinder, an outside air intake manifold supplied with outside air through a duct, a turbocharger compressor, and a heat exchanger downstream of the compressor and upstream of the intake manifold, wherein the engine further comprises an exhaust circuit, the exhaust circuit comprising an exhaust manifold, a turbocharger turbine, and, for example, a system for discharging the engine's combustion gases, arranged from upstream to downstream in the direction of the flow of the combustible gases.

[0017] The engine further includes a partial intake exhaust gas recirculation circuit that starts at a point in the exhaust circuit downstream of the turbine and opens into an outside air supply duct upstream of the turbocharger's compressor, and this intake circuit includes a control valve or throttle box installed between the compressor and the heat exchanger.

[0018] The method is, - A step of estimating the mass of liquid water accumulating on the inner wall of the heat exchanger in real time, - A step of comparing the estimated mass of water with a threshold, - If the estimated mass of water exceeds a threshold, the step of activating the purge of the intake air cooler by generating oscillations between the nominal flow rate and the increased flow rate of the intake air flowing into the heat exchanger, and oscillations between the nominal advance angle and the reduced advance angle of the ignition timing, It is equipped with.

[0019] These fluctuations in intake airflow allow for the maintenance of stable engine torque around the torque setting point while forcing the water accumulating on the walls of the cooler to remain stagnant.

[0020] The heat exchanger may be a cold water charge air cooler (W-CAC) or a charge air cooler (CAC).

[0021] Advantageously, the oscillation of the intake air flow is achieved by controlling the opening of the adjustment valve or throttle box by executing an oscillation between a nominal position corresponding to the engine operating point and an increased opening position, i.e., an additional opening position larger than the nominal position. In one possible embodiment, the increased opening position can be the maximum opening position of the throttle box, i.e., the fully open position.

[0022] Advantageously, the generation of the oscillation of the intake air flow flowing into the heat exchanger and the generation of the oscillation of the ignition timing advance are executed simultaneously.

[0023] For example, the oscillation or variation of the intake air flow constitutes an oscillation step between a nominal flow value and an increased flow value, and the generation of the oscillation of the ignition timing advance constitutes an oscillation step between a reduced advance value and a nominal advance value, and the nominal value of the ignition timing advance corresponds to the intake air flow and particularly to the nominal position of the adjustment valve or throttle box. The reduced advance value corresponds to an advance value less than the nominal advance value and reduces the combustion efficiency.

[0024] The oscillation step has, for example, the same time between the rising stage and the falling stage, for example, 1 second to 2 seconds, for example, 1.5 seconds.

[0025] Advantageously, the purge step has a duration consisting of 8 seconds to 12 seconds, for example, 10 seconds, which is necessary to discharge water from the charge air cooler.

[0026] According to a second aspect, the present invention relates to an electronic control unit for a spark ignition internal combustion engine including at least one cylinder, an outside air intake manifold to which outside air is supplied through a duct, a compressor of a turbocharger, and a heat exchanger downstream of the compressor and upstream of the intake manifold, the engine further including an exhaust circuit, the exhaust circuit including, in the direction of flow of the burned gas from upstream to downstream, an exhaust manifold, a turbine of the turbocharger, and, for example, a system for discharging the combustion gas of the engine.

[0027] The engine further includes a partial intake exhaust gas recirculation circuit that starts at a point in the exhaust circuit downstream of the turbine and opens into an outside air supply duct upstream of the turbocharger's compressor, and this intake circuit includes a control valve or throttle box installed between the compressor and the heat exchanger.

[0028] The electronic control unit is - A module that estimates the mass of liquid water accumulating on the inner wall of a heat exchanger in real time, - A module that compares the estimated mass of water with a threshold, - A module that activates the purge of the intake cooler when the estimated mass of water is greater than a threshold, and is configured to generate oscillations between the nominal flow rate and the increased flow rate of the intake air flowing into the heat exchanger, and oscillations between the nominal advance angle and the reduced advance angle of the ignition timing, It is equipped with an engine control system.

[0029] Advantageously, the module that operates the intake air cooler purge includes a module that controls the regulating valve or throttle box by performing oscillations between a nominal position corresponding to the engine operating point and an additional opening position.

[0030] Advantageously, the module that activates the intake air cooler purge includes an ignition timing advance modulator module configured to modulate the ignition timing advance between a nominal advance value and a reduced advance value.

[0031] In another embodiment, the present invention relates to a motor vehicle equipped with an electronic control unit as described above. [Brief explanation of the drawing]

[0032] [Figure 1] This diagram very schematically illustrates an exemplary structure of an internal combustion engine in a motor vehicle equipped with a control unit that incorporates the control system according to the present invention. [Figure 2] Figure 1 shows a rectangular wave graph of the control signal from the control system. [Figure 3]Figure 1 shows a block diagram of the control method according to the present invention, which is implemented by the control unit. [Modes for carrying out the invention]

[0033] Other problems, features, and advantages of the present invention will become apparent from the following description, which is given only by non-limiting examples and by reference to the accompanying drawings.

[0034] Figure 1 schematically shows the general structure of a motor vehicle, particularly a spark-ignition internal combustion engine 10 that operates on gasoline. As a modification, an engine that operates on alcohol or LPG-type liquefied gas may also be used.

[0035] These architectures are given as examples only and do not limit the present invention to configurations to which the engine control according to the present invention can be applied.

[0036] In the illustrated example, the internal combustion engine 10, in a non-limiting embodiment, comprises three inline cylinders 12, an outside air intake manifold 14, an exhaust manifold 16, and a turbocharging system, i.e., a turbocharger 18.

[0037] Cylinder 12 is supplied with air via an intake manifold 14 or intake distributor, and the intake manifold 14 itself is supplied with air via a duct 20 which is equipped with the engine 10's air filter 22 and the turbocharger 18's compressor 18b.

[0038] Each cylinder 12 is supplied with, for example, a gasoline-type fuel.

[0039] In a well-known embodiment, the turbocharger 18 includes, as essential components, a turbine 18a driven by exhaust gas and a compressor 18b mounted on the same axis or shaft as the turbine 18a for the purpose of increasing the amount of air (mass flow rate) introduced into the cylinder 12 of the engine 10, and ensuring the compression of the air distributed by the air filter 22. The turbine 18a may be of the "variable geometry" type, that is, the turbine impeller is equipped with variable inclined blades to modulate the amount of energy taken in from the exhaust gas and the resulting boost pressure.

[0040] The heat exchanger 26 is located behind the outlet of the compressor 18b, which supplies outside air to the duct 14a of the intake manifold 14.

[0041] Therefore, the internal combustion engine 10 includes an intake circuit Ca, an exhaust circuit Ce, and a fuel injection circuit (not shown).

[0042] In the intake circuit Ca, the air circulation direction is from upstream to downstream. - Air filter 22 or airbox, -The compressor 18b of the turbocharger 18 is configured to compress air taken from the external atmosphere and, if necessary, low-pressure recycled exhaust gas, as described later. - The throttle housing 24 or gas intake valve inside the engine, - A heat exchanger 26 configured to cool the intake gas corresponding to the mixture of outside air and recycled gas after it has been compressed in the compressor 18b, - Intake manifold 14 and, It is equipped with.

[0043] The heat exchanger 26 here is a cooler for the so-called "supercharged" intake gas, corresponding to an air-water exchanger, which in English terminology is called a "water-charged air cooler." The terms "heat exchanger 26" and "intake air cooler 26" shall refer to the same element hereafter. Alternatively, it may be an air-air cooler.

[0044] The intake circuit Ca may include a flow meter (not shown) located downstream of the air filter 22 within the intake duct 20, and the flow meter is configured to measure the actual value of the airflow rate entering the engine 10. The flow meter measures only the outside airflow rate.

[0045] The exhaust circuit Ce flows from upstream to downstream in the direction of the combustible gas flow. - Exhaust manifold 16 and, -A turbine 18a of a turbocharger 18 configured to extract energy from passing exhaust gases, wherein the expanded energy is transmitted to a compressor 18b via a common shaft for compression of intake gases, - The discharge control unit of the combustion gas system 40, It is equipped with.

[0046] With respect to the exhaust manifold 16, it recovers exhaust gas from combustion and discharges the exhaust gas to the outside via a gas exhaust duct 28 connected to the turbine 18a of the turbocharger 18 and via an exhaust line 30 attached downstream of the turbine 18a.

[0047] As a non-limiting example, the discharge control unit of the engine's combustion gas system 40 includes a first device 42 equipped with a three-way catalyst.

[0048] The gas release control system (combustion gas system) 40 further comprises a second device 55, which is a particulate filter, and an exhaust pipe 32 attached to the outlet of the second release control device 55 and opening outward.

[0049] As shown in the diagram, the engine 10 is equipped with a partial exhaust gas recirculation (EGR) circuit 50 in the intake section, which is called an "exhaust gas recirculation" circuit in Anglo-Saxon terminology.

[0050] This circuit 50, in this case an "EGR BP" low-pressure exhaust gas recirculation circuit, starts from a point in the exhaust pipe 32 downstream of the turbine 18a and, in particular in the case of Figure 1, downstream of the gas discharge control system 40, and returns the exhaust gas to a point upstream of the compressor 18b of the turbocharger 18, specifically downstream of the air filter 22, in the outside air supply duct 20.

[0051] In modified examples not shown, the low-pressure exhaust gas recirculation circuit starts from the outlet of the turbine 18a, or from only a portion of the gas release control system 40, for example, between the first release control device 42 and the second release control device 55.

[0052] As shown in the figure, the recirculation circuit 50 includes a "V EGR BP" control valve 52 configured to adjust the exhaust gas flow to a low pressure in the direction of the recirculated gas flow, and an EGR gas cooler 54. The "V EGR LP" valve 52 is located upstream of the cooler 54, which is located upstream of the compressor 18b.

[0053] As a non-limiting example, an engine may be associated with a fuel circuit comprising fuel injectors (not referenced) that directly inject gasoline from a fuel tank (not shown) into each cylinder.

[0054] The engine includes an electronic control unit (ECU) 60 which has a control system 70 configured to control various elements of the internal combustion engine, and in particular the throttle box 24 and the ignition timing advance angle.

[0055] The control system 70 receives data or estimates collected by sensors at various locations within the engine.

[0056] The control system 70 may receive other data, such as temperature or other pressures at various locations within the engine.

[0057] The control system 70 includes a module 71 that estimates the mass M_water of liquid water accumulating on the inner wall of the heat exchanger 26 in real time.

[0058] Real-time estimation of the mass M_water of liquid water accumulating on the inner wall of the heat exchanger 26 can be performed, for example, as a function of the temperature of the incoming outside air, the airflow rate obtained by the flow meter, and the ambient relative humidity, by a humidity sensor located inside the intake circuit Ca, for example, inside a flow meter, or outside the vehicle, particularly by a weather service if the vehicle is a so-called "connected" vehicle, or by the method described in French Patent No. 3064678.

[0059] The control system 70 includes a module 72 that compares an estimated value of the water mass M_water with a threshold S.

[0060] The threshold S can correspond to the maximum mass of liquid water that can remain in the heat exchanger 26.

[0061] To determine the threshold S, the heat exchanger 26 may be weighed, for example, in a dry state. The volume normally traversed by a mixture of air and EGR gas is completely filled with water, and the heat exchanger 26 is placed on a test bench and passed through at a constant airflow rate until the water contained therein is mechanically discharged, without waiting for the water to evaporate. The heat exchanger 26 is then weighed to estimate the mass of water it held. This mass corresponds to the threshold S of liquid water that can be retained for the constant airflow rate under consideration.

[0062] Alternatively, the threshold S may correspond to the critical mass of water that, if a desorption phenomenon occurs, for example, after an acceleration request, or if there is a significant increase in the airflow rate supplied by the engine, poses a risk of extinguishing the combustion.

[0063] The critical mass of water can be estimated by testing on a fixed engine bench by injecting increasing masses of liquid water into the cylinder intake and measuring the internal combustion pressure, thereby allowing us to estimate the resulting regulated torque. We then estimate the maximum allowable mass of liquid water for each combustion cycle and each cylinder to address combustion defects.

[0064] Furthermore, the critical mass of water for the engine can be estimated by understanding the engine dynamics, that is, the duration required to reach the critical stage of the engine and therefore the number of combustion cycles.

[0065] The control system 70 includes a module 74 that activates purging of the cooler 26 when the estimated value of the water mass M_water is greater than a threshold S.

[0066] Module 74, which operates the purge, includes module 76, which controls a throttle box configured to generate fluctuations in intake airflow between a nominal flow rate (Qaf_name) and an increased flow rate (Qaf_+). These fluctuations in intake airflow are obtained by controlling the opening of the throttle box 24 by oscillations between a nominal position (%BP_name) and an additional opening position (%BP_+) corresponding to the associated engine operating point. In one embodiment, the increased flow rate may be equal to the maximum engine flow rate corresponding to the fully open position of the throttle box. More generally, this is a flow rate greater than the nominal flow rate.

[0067] These fluctuations in intake air flow rate make it possible to force the water accumulating on the walls of the cooler 26 to remain stagnant.

[0068] These intake flow rate variations are obtained by setting the throttle to an opening of the throttle housing 24 between the nominal position %BP_name and the additional opening position %BP_+ of the associated engine operating point.

[0069] Module 74, which activates the purge, further comprises Module 78, which modulates the ignition timing advance, configured to modulate the ignition timing advance between a nominal advance value AV_name and a reduced advance value AV_-. "Reduced advance" means an advance value less than the nominal advance value, which results in a decrease in combustion efficiency.

[0070] The intake airflow rate Qaf and ignition timing advance angle AV are provided by an engine computer (not shown) integrated into the ECU, and consist of pairs of airflow rate / ignition timing advance angle values ​​for engine speed / load operating point.

[0071] By modulating the ignition timing advance, it becomes possible to maintain engine torque at a constant level equal to the engine torque required by the driver when the accelerator pedal is pressed.

[0072] Naturally, starting from the optimal operation corresponding to the nominal airflow value Qaf_name and nominal ignition timing value AV_name (generally corresponding to the optimal ignition timing or values ​​near the optimal ignition timing), if the airflow rate is increased while maintaining the normal operation of a spark ignition engine at a stoichiometric mixture ratio equal to 1, an unnecessary excess of engine torque will be obtained if the ignition timing is not reduced. This is because the air-fuel mixture flow rate is higher while the combustion efficiency remains the same. Here, a controlled reduction of the ignition timing makes it possible to reduce the combustion efficiency so that the same engine torque as obtained with the nominal airflow and nominal ignition timing is obtained.

[0073] Figure 2 shows stepped graphs of intake air flow rate Qaf, ignition timing advance AV, engine torque C, and throttle opening percentage %BP passing through the heat exchanger 26, as functions of time in seconds.

[0074] As can be seen from Figure 2, fluctuations in intake airflow constitute an oscillation step between the nominal flow rate value Qaf_name and the increased flow rate value Qaf_+, modulation of ignition advance angle constitutes an oscillation step between the decreased advance angle value AV_- and the nominal advance angle value AV_name, and the nominal position of the ignition advance angle corresponds to the nominal position of the throttle box 24 and the intake airflow.

[0075] The slot preferably has the same time τ between the rising and falling phases, for example, 1 to 2 seconds, or for example, 1.5 seconds.

[0076] For example, the duration δt of the purging phase required to discharge water from the cooler 26 is 8 to 12 seconds, which is equal to, for example, 10 seconds.

[0077] As shown in detail in Figure 3, the engine control method 100 includes a step 102 of estimating in real time the mass M_water of liquid water accumulating on the inner wall of the heat exchanger 26.

[0078] The method 100 for controlling the engine further comprises step 104 of comparing an estimate of the mass of water M_water with a threshold S.

[0079] The method 100 for controlling the engine further comprises step 110 of activating the purging of the cooler 26 when the estimated value of the water mass M_water is greater than a threshold S.

[0080] Step 110, which activates the purging of the heat exchanger 26, comprises Step 112, which controls the throttle box 24, during Step 112, the throttle box opening is generated by performing oscillations between the nominal position %BP_name and the additional opening position %BP_+ of the associated engine operating point in order to generate fluctuations in intake airflow between the nominal flow rate value Qaf_name and the increased flow rate value Qaf_+.

[0081] Step 110, which activates the purging of the heat exchanger 26, further comprises step 114, which modulates the ignition timing advance, which is configured to modulate the ignition timing advance between a nominal advance value AV_name and a reduced advance value AV_-.

[0082] As mentioned above, by modulating the ignition timing advance, it is possible to maintain a constant level of engine torque equal to the engine torque required by the driver when the accelerator pedal is pressed.

[0083] Step 112, which controls the throttle box 24, and step 114, which modulates the ignition timing advance, are performed simultaneously.

[0084] The present invention makes it possible to purge the air cooler while maintaining the torque generated by the engine at a constant level near the target value, thereby avoiding any risks of rapid detachment and extinguishing of engine combustion.

Claims

1. A method (100) for controlling a spark-ignition internal combustion engine (10) comprising at least one cylinder (12), an outside air intake manifold (14) supplied with outside air through a duct (20), a compressor (18b) of a turbocharger (18), and a heat exchanger (26) downstream of the compressor (18b) and upstream of the intake manifold (14), wherein the engine further comprises an exhaust circuit (Ce), the exhaust circuit (Ce) is configured to flow from upstream to downstream in the direction of the flow of the combustible gas, and the exhaust manifold The turbocharger (18) comprises a hold (16), a turbine (18a) of the turbocharger (18), and a partial recirculation circuit (50) of exhaust gas in the intake section, the partial recirculation circuit (50) starting at one point in the exhaust circuit (Ce) downstream of the turbine (18a), and opening outward into the outside air supply duct (20) upstream of the compressor (18b) of the turbocharger (18), and the intake circuit (Ca) comprises a control valve (24) installed between the compressor (18b) and the heat exchanger (26), The steps include: estimating in real time the mass (M_water) of liquid water accumulating on the inner wall of the heat exchanger (26); The steps include comparing the estimated mass (M_water) with a threshold (S), If the estimated value of the water mass (M_water) is greater than the threshold (S), the purging of the heat exchanger (26) is activated by generating oscillations between the nominal flow rate value (Qaf_name) and the increased flow rate value (Qaf_+) of the intake air flow rate (Qaf) flowing into the heat exchanger (26), and oscillations between the nominal advance angle value (AV_name) and the reduced advance angle value (AV_-) of the ignition timing advance angle (AV). A method for providing this.

2. The method according to claim 1, wherein the oscillation of the intake airflow rate (Qaf) is achieved by controlling the opening of the adjustment valve (24) by performing an oscillation between a nominal position (%BP_name) corresponding to the engine operating point and an additional opening position (%BP_+).

3. The method according to claim 1 or 2, wherein the generation of vibrations in the intake air flow rate (Qaf) flowing into the heat exchanger (26) and the generation of vibrations in the ignition timing advance angle (AV) are performed simultaneously.

4. The method according to any one of claims 1 to 3, wherein the vibration of the intake airflow constitutes a vibration step between the nominal flow rate value (Qaf_name) and the increased flow rate value (Qaf_+), the generation of vibration of the ignition timing advance constitutes a vibration step between the decreased advance value (AV_-) and the nominal advance value (AV_name), and the nominal value of the ignition timing advance corresponds to the nominal position of the intake airflow (Qaf_name) and, in particular, the nominal position of the adjustment valve or throttle box (24).

5. The method according to claim 4, wherein the slot has the same time (τ) between the rising and falling phases, for example, 1 to 2 seconds, for example, 1.5 seconds.

6. The method according to claim 4 or 5, wherein the purging step has a duration (δt) of 8 to 12 seconds, preferably 10 seconds, required to discharge water from the heat exchanger (26).

7. An electronic control unit (ECU) for a spark-ignition internal combustion engine (10) comprising at least one cylinder (12), an outside air intake manifold (14) supplied with outside air through a duct (20), a compressor (18b) of a turbocharger (18), and a heat exchanger (26) downstream of the compressor (18b) and upstream of the intake manifold (14), wherein the engine further comprises an exhaust circuit (Ce), the exhaust circuit (Ce) having an exhaust manifold running from upstream to downstream in the direction of the flow of the combustible gases The nifold (16), the turbine (18a) of the turbocharger (18), and a partial exhaust gas recirculation circuit (50) in the intake section, the partial exhaust gas recirculation circuit (50) starting from a point in the exhaust circuit (Ce) downstream of the turbine (18a) and opening into the outside air supply duct (20) upstream of the compressor (18b) of the turbocharger (18), and the intake circuit (Ca) includes an adjustment valve (24) installed between the compressor (18b) and the heat exchanger (26), An engine control system (70), A module (71) for real-time estimation of the mass (M_water) of liquid water accumulating on the inner wall of the heat exchanger (26), A module (72) that compares the estimated mass of water (M_water) with a threshold (S), A module (74) that activates purging of the heat exchanger (26) when the estimated mass of the water (M_water) is greater than the threshold (S), the module (74) is configured to generate oscillations between the nominal flow rate value (Qaf_name) and the increased flow rate value (Qaf_+) of the intake air flow rate (Qaf) flowing into the heat exchanger (26), and oscillations between the nominal advance angle value (AV_name) and the decreased advance angle value (AV_-) of the ignition timing advance angle (AV), An electronic control unit (ECU) equipped with an engine control system (70) that includes the following.

8. The electronic control unit (ECU) according to claim 7, wherein the module (74) for activating the purge of the heat exchanger (26) comprises a module (76) for controlling the adjustment valve (24) by performing vibrations between a nominal position (%BP_name) corresponding to the engine operating point and an additional opening position (%BP_+).

9. The electronic control unit (ECU) according to claim 7 or 8, wherein the module (74) for activating the purge of the heat exchanger (26) comprises an ignition timing advance modulator module (78) configured to modulate the ignition timing advance between the nominal advance value (AV_name) and the reduced advance value (AV_-).

10. A motor vehicle comprising an electronic control unit according to any one of claims 7 to 9.

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