DE102011087260A1 - Arrangement for recirculating exhaust gas and supplying cooled charge air to multi-cylinder internal combustion engine in motor vehicle, has control unit controlling gas mass flow via cooling stages and/or controlling flow through bypass - Google Patents

Abstract

The arrangement has an exhaust gas cooling arrangement comprising a two-stage exhaust gas cooler (16) with two cooling stages e.g. high temperature and low temperature cooling stages (20, 21). A temperature sensor (18) measures temperature of exhaust gas and/or charge air. A control unit controls exhaust gas mass flow through the stages and/or controls mass flow through a bypass (17) and/or controls charge air mass flow through a charge air cooler (25) and/or controls mass flow through another bypass (19). Another temperature sensor (31) is arranged at an outlet side of the air cooler. An independent claim is also included for a method for controlling an arrangement for recirculating exhaust gas and supplying cooled charge air to an internal combustion engine.

Description

Technical area

The invention relates to an arrangement for recirculating exhaust gas and supplying cooled charge air to an internal combustion engine, wherein the internal combustion engine has an exhaust gas charging and an exhaust gas cooling arrangement, in particular according to the preamble of claim 1. Furthermore, the invention relates to a related method.

State of the art

Arrangements for recirculating exhaust gas and for supplying cooled charge air to an internal combustion engine are widely known in the art. So by signing up DE 10 2008 045 479 A1 a system has become known for the recirculation of exhaust gas of an internal combustion engine, the internal combustion engine having an exhaust system with a high pressure and a low pressure part, the system having a separator which is adapted to separate a condensate from an exhaust gas of the high pressure part of the exhaust system and the Introduce condensate through a discharge line in the low-pressure part of the exhaust system in order to divert it from the exhaust system.

The generation of a condensate in internal combustion engines with exhaust systems or charge air systems is thus known as a disadvantageous effect in such devices in certain operating states.

The condensate is an acidic condensate with about pH 1 to 2, the u. a. Contains sulfuric and nitric acid, and due to its aggressive acidic properties leads to increased corrosion of the components of the arrangement for recirculation of exhaust gas and for supplying cooled charge air to an internal combustion engine.

According to the DE 10 2008 045 479 A1 This condensate is separated by a separator from the recirculated exhaust gas and fed to the low pressure side of the exhaust system after an exhaust aftertreatment unit in the exhaust pipe to get from there into the environment.

This has the disadvantage, in particular for the internal combustion engine and its components, that the condensate in the region of the exhaust gas cooler basically arises in certain operating states and can there already lead to increased corrosion before it is separated and discharged.

The publication DE 10 2005 008 103 A1 discloses an exhaust gas turbocharger internal combustion engine, in the high-pressure side, an exhaust gas recirculation is performed, wherein the exhaust gas turbocharger internal combustion engine has a condensate collection and / or discharge device to collect and dissipate the resulting condensate of the exhaust gas heat exchanger. Again, the condensate is formed in the exhaust gas heat exchanger and leads there to increased corrosion.

The publication DE 10 2005 023 958 A1 also discloses a turbocharger arrangement in which a condensate is formed in the exhaust gas cooler, wherein the condensate is disposed of by means of a condensate separator and a downstream thermal condensate disposal, so that the acids contained in the condensate are preferably converted into their harmless gases and water.

All of the listed publications allow in the exhaust gas cooler that a condensate is produced, which leads to increased corrosion of the components of the internal combustion engine. Since the condensate is liquid, it can also come in the engine to drip, which can also lead to significant damage of components of the internal combustion engine.

Presentation of the invention, object, solution, advantages

It is the object of the invention to provide an arrangement for recycling exhaust gas and for supplying cooled charge air to an internal combustion engine, which is substantially protected from generation of acidic condensate or generation of such an acidic condensate is at least substantially reduced. It is also the object of the invention to provide a related method, by means of which the formation of acidic condensate can be substantially reduced or even avoided.

The object of the arrangement is achieved with the features of claim 1, according to which an arrangement for the return of exhaust gas and supply of cooled charge air to an internal combustion engine is provided, wherein the internal combustion engine has an exhaust gas charging and an exhaust gas cooling arrangement, which is characterized by an exhaust gas cooling arrangement with a two-stage exhaust gas cooler with a first cooling stage and with a second cooling stage, with at least one bypass for bypassing the first and / or second cooling stage of the exhaust gas cooler and with at least one exhaust gas control valve, with at least a first charge air cooler and a bypass for bypassing the first charge air cooler and a charge air control valve, with at least one temperature sensor for measuring the exhaust gas and / or charge air temperature, with a control unit for controlling the exhaust gas mass flow through the first and / or by the second cooling stage of the exhaust gas cooler and / or for controlling the mass flow through the bypass to bypass the first and / or second cooling stage of the exhaust gas cooler and / or for controlling the charge air mass flow through the first charge air cooler and / or for controlling the mass flow through the bypass for bypassing the first charge air cooler to prevent condensation in the exhaust gas cooler and / or in the first intercooler.

By measuring the temperatures and the mass flows, the control of the mass flows can take place in essentially any operating situation such that the generation of acidic condensate in the exhaust gas cooler and / or in the charge air cooler is greatly reduced or even prevented, at least in some operating states.

This also allows operating situations of the internal combustion engine to be specifically controlled in order to reliably avoid condensate in this operating situation. Thus, before a shutdown of the engine for a driver-side shutdown this previously targeted to be controlled in an operating situation in which the condensate does not accumulate or in which a previously possibly formed condensate is deliberately evaporated and removed.

The formation of condensate can also be reduced or prevented by determining, as a function of at least one detected mass flow and / or at least one temperature, an operating state in which condensate could form, so that an operating state of the internal combustion engine is triggered by a changed control of the internal combustion engine , in which no or only a reduced condensate would occur.

The control can also be extrapolated into the future, so that it is foreseeable that a condensate could occur at a given operating state, if it would continue to develop as in the present case, so that the development of the operating state would interfere with the expected operating state with condensate production to avoid.

It is expedient if, furthermore, a heater is provided in the bypass of the first charge air cooler whose heating power is controllable by the control unit to prevent condensation. This makes the charge air after the intercooler heatable and adjustable in temperature.

It is also advantageous if a first valve and / or a second valve is provided for controlling the exhaust gas mass flow through the first and / or the second cooling stage of the exhaust gas cooler and / or for controlling the mass flow through at least one bypass for bypassing the first and / or second cooling stage of the exhaust gas cooler or by a bypass for bypassing the first cooling stage of the exhaust gas cooler. In this case, a second bypass may be provided to bypass only the first cooling stage, wherein the first bypass would bypass the first and the second cooling stage.

Furthermore, it is expedient if a third valve is provided as the charge air control valve for controlling the charge air mass flow through the first charge air cooler and / or for controlling the charge air mass flow through a bypass to bypass the first charge air cooler. Thus, the amount of charge air can be controlled by the radiator or by the bypass.

It is also advantageous if a fourth valve is provided for controlling the coolant mass flow through the first charge air cooler.

Furthermore, it is expedient if a first temperature sensor is arranged on the output side of the first and / or second cooling stage of the exhaust gas cooler. Preferably, the temperature sensor is arranged after the inflow of the bypass to the outlet of the exhaust gas cooler, so that it can measure a mixing temperature between the cooled exhaust gas and the bypassed exhaust gas.

It is also advantageous if a second temperature sensor is arranged on the output side of the first charge air cooler. Preferably, this temperature sensor is arranged after the inflow of the bypass to the output of the charge air cooler, so that it can measure a mixing temperature between the cooled charge air and the bypassed charge air.

The object is achieved with regard to the method by a method for controlling an arrangement for recycling exhaust gas and supplying cooled charge air to an internal combustion engine, wherein the internal combustion engine has an exhaust gas charging and an exhaust gas cooling arrangement with an exhaust gas cooling arrangement with a two-stage exhaust gas cooler with a first cooling stage and with a second cooling stage, with at least one bypass for bypassing the first and / or second cooling stage of the exhaust gas cooler and with at least one exhaust control valve, further comprising at least a first charge air cooler and a bypass for bypassing the first charge air cooler and with a charge air control valve, further comprising at least one temperature sensor for Measurement of the exhaust gas and / or charge air temperature, further comprising a control unit for controlling the exhaust gas mass flow through the first and / or by the second cooling stage of the exhaust gas cooler and / or Control of the mass flow through the bypass to bypass the first and / or second cooling stage of the exhaust gas cooler and / or for controlling the charge air mass flow through the first charge air cooler and / or for controlling the mass flow through the bypass to bypass the first charge air cooler to prevent condensation in the exhaust gas cooler and In the first charge air cooler, the exhaust gas mass flow and / or the charge air mass flow is controlled in dependence on the temperature of the exhaust gas flow and / or the charge air temperature such that substantially no condensate is generated.

In this case, it is advantageous if, further by means of a heater in the bypass of the first charge air cooler, the charge air conducted through is heated in a controlled manner, in particular to avoid condensate formation.

It is also advantageous if, by means of a first valve and / or a second valve, control of the exhaust gas mass flow is controlled by the first and / or the second cooling stage of the exhaust gas cooler and / or by a bypass for bypassing the first and / or second cooling stage of Exhaust gas cooler or by a bypass to bypass the first cooling stage of the exhaust gas cooler.

It is also advantageous if by means of a third valve, a control of the charge air mass flow through the first charge air cooler and / or a control of the charge air mass flow through a bypass to bypass the first charge air cooler takes place.

Furthermore, it is expedient if by means of a fourth valve, a control of the coolant mass flow through the first charge air cooler takes place.

By the arrangement according to the invention and by the method according to the invention a low cold start emission is achieved. The condensate reduction or condensate avoidance is achieved during operation and in engine stop situations

Further advantageous embodiments are described by the following description of the figures and by the subclaims.

Brief description of the drawings

The invention will be explained in more detail on the basis of at least one embodiment with reference to the drawings. Show it:

1 an embodiment of an inventive arrangement.

Preferred embodiment of the invention

The 1 shows an arrangement for the return of exhaust gas and for supplying cooled charge air to an internal combustion engine 1 , which is shown schematically. In this case, the internal combustion engine is a multi-cylinder internal combustion engine with a plurality of cylinders 2 shown, which can be done without any restriction of generality with any number of cylinders.

The internal combustion engine is the air for the combustion of the fuel via a suction module 3 to the respective cylinders 2 fed, this suction module 3 the air on the cylinders 2 distributed according to the requirements of the respective operating state. The exhaust gas from the cylinders 2 is via an exhaust manifold 4 collected and via an exhaust pipe 5 dissipated.

In this case, the exhaust gas is fed to a two-stage charging arrangement. The two-stage charging arrangement is characterized by two turbochargers 6 . 7 illustrated, wherein the exhaust gas from the exhaust gas outlet pipe 5 on a first turbine 8th the first turbocharger 6 and from there via the connecting line nine to a second turbine 10 of the second turbocharger 7 is passed on. Starting from the turbine 10 is the exhaust gas over the line 11 an optional particulate filter or other aftertreatment device 12 fed and from there an outlet 13 from where it is released, for example by a muffler of the motor vehicle into the environment.

In addition to a discharge of the exhaust gas via the lines 5 and the subsequent turbochargers 6 . 7 to the line 13 can also be a return of exhaust gas via the line 14 to the internal combustion engine. In this case, the exhaust gas from the exhaust manifold 4 into the pipe 14 fed, via a corresponding existing valve 15 guided and via an exhaust gas heat exchanger 16 the suction pipe 3 returned to the internal combustion engine. Parallel to the exhaust gas heat exchanger 16 is still a bypass line 17 provided, through which also exhaust gas can flow. This exhaust gas is again the intake manifold 3 fed. The division of the amount of exhaust gas, which over the exhaust gas cooler 16 flows through or through the bypass 17 flows through the control of the valve 15 , Where appropriate, if appropriate, the total amount of recirculated exhaust gas can be controlled as well as their allocation to the exhaust gas heat exchanger 16 and on the bypass 17 , Thus, the valve 15 not only control the distribution of the exhaust gas between the heat exchanger and the bypass, but also adjust the total amount of recirculated exhaust gas, which takes place depending on the operating state via an electronic control can. The valve 15 can be advantageously designed as an integrated valve with the realization of the two functions. Alternatively, however, it can also be realized by two individual valves, a valve which adjusts the amount of exhaust gas flowing through, and a valve which regulates the division between the flow through the heat exchanger 16 and the flow through the bypass 17 controls.

At the exit of the heat exchanger 16 is a temperature sensor 18 provided, which is advantageous after merging the lines of the bypass 17 and the exhaust heat exchanger output is arranged to a mixing temperature of the exhaust gas to the exhaust gas heat exchanger 16 and after bypass 17 to be able to detect. Optionally, it may also be sufficient if the temperature of the exhaust gas at the outlet of the exhaust gas heat exchanger 16 itself is measured. It is advantageous if the amount of exhaust gas flowing through the bypass can be determined, the typical temperature of which can also be estimated. As a result, a mixing temperature can also be determined. Optionally, it may also be sufficient if the temperature at the outlet of the bypass line is detected.

The exhaust gas heat exchanger 16 is advantageously formed in two stages and has a first cooling stage, which is also high-temperature cooling stage 20 is called. Furthermore, the exhaust gas heat exchanger 16 a second cooling stage, which also low-temperature cooling stage 21 is called. Here is the high-temperature cooling stage 20 the low temperature cooling stage 21 considered upstream in the exhaust stream. The high temperature stage is advantageous 20 and the low temperature stage 21 the exhaust gas heat exchanger 16 formed in one piece, so that the exhaust only an exhaust heat exchanger as such with two cooling stages 20 . 21 flows through, which are designed as a structural unit. Alternatively, the exhaust gas heat exchanger 16 be modular with the two cooling stages, and from two individual heat exchangers 20 . 21 exist, which are fluidly connected to each other, for example via a pipe connection, so that the exhaust gas first through the first heat exchanger 20 with the first cooling stage and then outflow from this heat exchanger 20 in a second heat exchanger 21 the second cooling stage flows. As the exhaust gas is thus first cooled to a temperature in the first cooling stage of the heat exchanger, wherein the cooling preferably corresponds to the cooling with a normal cooling fluid of the internal combustion engine, so that the temperature corresponds approximately to the cooling fluid temperature of the cooling circuit. Subsequently, this already pre-cooled exhaust gas flows through the second cooling stage 21 the exhaust gas heat exchanger 16 , which is preferably cooled with a second cooling fluid, which preferably has a lower temperature than the first cooling fluid. The second cooling fluid is thus a so-called low-temperature cooling fluid. This ensures that the exhaust gas in the second cooling stage 21 once again from the outlet temperature of the first heat exchanger 20 is cooled to a final temperature T _end , which is significantly reduced compared to the output temperature T _{aus-stufe1 of} the first heat exchanger.

The first cooling stage 20 the exhaust gas heat exchanger 16 has a bypass 19 which is controllable via a valve which in 1 however not shown. It can reduce the amount of exhaust gas passing through the bypass 19 flows through or through the first cooling stage 20 flows are adjusted by means of this valve. In this case, this valve, not shown, is advantageous in the input diffuser of the heat exchanger 16 or the first cooling stage 20 arranged or upstream of this. The bypass 19 ends accordingly at the exit of the heat transfer area of the first cooling stage 20 and becomes between the end portion of the first heat transfer region of the first cooling stage 20 and the entrance area of the second heat transfer area of the second cooling stage 21 reintroduced. It is thus achieved that this is the first heat transfer area of the first cooling stage 20 immediate exhaust gas through the second cooling stage 21 nevertheless coolable.

The suction tube 3 is fresh air for the burns in the cylinders of the internal combustion engine 1 fed. In this case, this fresh air is supplied as so-called charge air under charged pressure. The supply takes place through the input line 22 , with the air from the pipe 22 coming from the turbine 23 of the turbocharger 7 charged and placed under a first pressure, so that in the output line 24 the first turbocharger 7 the charge air is brought to a first average charge air pressure p _medium . The charge air then flows through a first intercooler 25 , which is also referred to as low pressure charge air cooler. On the output side of the intercooler 25 the charge air flows through the turbine 26 of the second turbocharger 6 and is then charged to a second higher pressure level p _high . Output side of the turbocharger 6 will be in the lead 27 the charge air then via a valve 28 a second intercooler 29 , the high-pressure charge air cooler supplied. The high pressure charge air cooler 29 cools the charge air in turn, so that the output side of the intercooler 29 there is a charge air at low temperature.

Parallel to the intercooler 29 is a bypass 30 arranged, which can be traversed by the charge air in the high pressure region. The dependence of the amount of charge air passing through the heat exchanger 29 flows through or through the bypass 30 flows through the valve 28 controlled. The valve can 28 both the distribution and the amount of the intercooler 29 controlling the charge air flowing through. Output side of the bypass 30 or the heat exchanger 29 then it flows charge air into the intake manifold 3 , wherein previously an admixture of the recirculated exhaust gas to the charge air takes place. This is done at the point 63 at which the exhaust pipe is connected to the charge air line.

At the exit of the heat exchanger 29 is a temperature sensor 31 provided, which is the temperature of the charge air at the outlet of the intercooler 29 detected.

The bypass 30 is designed such that it has a heater 32 that bypasses the by-pass 30 flowing charge air can heat up by heating. Thereby the heating can 32 for example, electronically controlled and electrically operated.

Due to the heating in the area of the bypass 30 of the intercooler 29 An admixing of heated charge air to the cooled charge air can be carried out in such a way that the final temperature of the charge air can be selectively adjusted before it reaches the intake manifold 3 is supplied.

Furthermore, it can be seen that the internal combustion engine 1 a first cooling circuit 33 and a second cooling circuit 34 includes. The first cooling circuit 33 represents the cooling circuit for the internal combustion engine as such, which can also be referred to as high-temperature cooling circuit. The cooling circuit 34 is one compared to the temperature of the first cooling circuit 33 lowered in temperature cooling circuit, which can also be referred to as a low-temperature circuit. The cooling circuit 33 has a pump 35 on, which introduces coolant into the engine housing of the internal combustion engine. There, the coolant flows through the internal combustion engine and leaves the output side of the internal combustion engine with an increased coolant temperature. The coolant flows through the pipe 36 from the internal combustion engine 1 off and on via the thermostatic valve 37 either a bypass 38 and / or a coolant cooler 39 supplied, wherein, depending on the coolant temperature, the thermostat 37 controls the amount of coolant that passes either through the bypass 38 and / or through the heat exchanger 39 flows. On the output side of the heat exchanger 39 the coolant flows through the pump again 35 to the internal combustion engine 1 back. Furthermore, there is a fan 40 shown, for example, the electronically controlled the cooling air for the radiator 39 can adjust.

The cooling circuit 33 also feeds via a secondary channel 41 the coolant to flow through the first exhaust gas heat exchanger 16 or the first cooling stage 20 the exhaust gas heat exchanger 16 , so that the coolant in the area of a connection in the heat exchanger 16 or the first cooling stage 20 can flow in, the heat exchanger 16 or the first cooling stage 20 can flow through and over the line 42 after an outflow from the heat exchanger 16 or from the first cooling stage 20 back to the cooling circuit 33 can be returned.

Thus, the first cooling stage 20 the exhaust gas heat exchanger 16 by a coolant mass flow of the first coolant circuit 33 cooled.

The second coolant circuit 34 , the low-temperature circuit, has a coolant radiator 43 which prefers the coolant cooler 39 the high temperature cooling circuit 33 is upstream in the air flow of the motor vehicle, so that the cooling air first, the low-temperature coolant radiator 43 flows through before the already warmed up cooling air 44 the high-temperature coolant cooler 39 flows through.

With the pump 45 the low-temperature coolant is passed over the line 46 and over the line 47 to the low-pressure charge air cooler 25 passed, there, the low-temperature coolant flows through the intercooler 25 , where the flow through the valve 48 at the outlet of the intercooler 25 is controlled. Subsequently, the coolant flows through the conduit 49 back to the radiator 43 , Starting from the line 46 Coolant also flows through the pipe 50 to the second intercooler 29 flows through it, whereby here again a valve 51 the mass flow of the low-temperature coolant through the intercooler 29 can control. After leaving the low-temperature coolant, this flows through the outlet line 52 back to the low-temperature coolant cooler 43 ,

According to the invention, the arrangement is now designed and operated by a control method that by means of a control unit 60 for controlling the exhaust gas mass flow through the first and / or through the second cooling stage 20 . 21 of the exhaust gas cooler 16 and / or for controlling the mass flow through the bypass 19 to bypass the first cooling stage and / or through the bypass 17 to bypass the first and / or second cooling stage 20 . 21 of the exhaust gas cooler 16 and / or for controlling the charge air mass flow through the first charge air cooler 29 and / or for controlling the mass flow through the bypass 30 to bypass the first charge air cooler condensate formation in the exhaust gas cooler 16 or in the intercooler 29 should be avoided. The mass flows of the exhaust gas, for example, on the basis of the valve positions of the valves 15 and or 28 detected. The valve can 15 can be set controlled, so that the resulting mass flow can be determined based on the valve position. The same applies to the adjustment of the valve 28 , so that the mass flow through the intercooler 29 or by the relevant bypass 30 be determined as well can. Furthermore, by means of the sensors 18 . 31 the temperatures of the exhaust gas or charge air flows are determined. Also, the heating state of the auxiliary heater 32 in the bypass 30 of the intercooler 29 can be determined and finally through the valve 48 or through the valve 51 respectively through the valve 37 the coolant flow through the intercooler 25 . 29 or by the exhaust gas cooler stages 20 . 21 can be defined and determined so that all these signals are available to a controller in the control unit 60 so that the exhaust gas or charge air is adjusted in such a way that the condensate accumulation is avoided via the set mass flow and the set temperature of the coolant.

For this purpose, the mentioned input signals 61 Optionally used for the corresponding control signals 62 to determine for the actuators, so that by a corresponding adjustment of the valves or the heating power condensate generation can be avoided.

The setting of a corresponding operating state of the internal combustion engine is preferably carried out in such operating conditions in which a condensate formation would occur even with an expected development of the operating state, so that the formation of condensation can be predicted by a predictive control, wherein by changing the settings of the arrangement it can be prevented that the condensate is actually generated. This can be done, for example, in an engine stop situation after the driver has signaled an engine stop request by, for example, an operation of a key or an ignition on or off button, so that before switching off the engine an operating situation is brought about, which avoids a safe avoidance of condensate in the shutdown situation ,

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102008045479 A1 [0002, 0005]
• DE 102005008103 A1 [0007]
• DE 102005023958 A1 [0008]

Claims (12)

Arrangement for recirculating exhaust gas and supplying cooled charge air to an internal combustion engine, wherein the internal combustion engine has an exhaust gas charging and an exhaust gas cooling arrangement, characterized by An exhaust gas cooling arrangement having a two-stage exhaust gas cooler with a first cooling stage and with a second cooling stage, with at least one bypass for bypassing the first and / or second cooling stage of the exhaust gas cooler and with at least one exhaust gas control valve, At least a first intercooler and a bypass for bypassing the first intercooler and with a charge air control valve, - At least one temperature sensor for measuring the exhaust gas and / or charge air temperature With a control unit for controlling the exhaust gas mass flow through the first and / or the second cooling stage of the exhaust gas cooler and / or for controlling the mass flow through the bypass to bypass the first and / or second cooling stage of the exhaust gas cooler and / or for controlling the charge air mass flow through the first intercooler and / or for controlling the mass flow through the bypass to bypass the first intercooler to avoid condensation in the exhaust gas cooler and / or in the first intercooler. Arrangement according to claim 1, characterized in that furthermore a heater is provided in the bypass of the first intercooler whose heating power is controllable to prevent condensation from the control unit. Arrangement according to claim 1 or 2, characterized in that the exhaust control valve, a first valve and / or a second valve is provided for controlling the exhaust gas mass flow through the first and / or by the second cooling stage of the exhaust gas cooler and / or for controlling the mass flow through a bypass for bypassing the first and / or second cooling stage of the exhaust gas cooler or by a bypass for bypassing the first cooling stage of the exhaust gas cooler. Arrangement according to claim 1, 2 or 3, characterized in that as a charge air control valve, a third valve is provided for controlling the charge air mass flow through the first charge air cooler and / or for controlling the charge air mass flow through a bypass to bypass the first charge air cooler. Arrangement according to claim 1, 2, 3 or 4, characterized in that a fourth valve is provided for controlling the coolant mass flow through the first charge air cooler. Arrangement according to one of claims 1 to 5, characterized in that a first temperature sensor is arranged on the output side of the first and / or second cooling stage of the exhaust gas cooler. Arrangement according to one of claims 1 to 6, characterized in that a second temperature sensor is arranged on the output side of the first charge air cooler. A method of controlling an exhaust gas recirculation system and supplying cooled charge air to an internal combustion engine, the internal combustion engine comprising an exhaust gas charging and an exhaust gas cooling arrangement comprising: An exhaust gas cooling arrangement having a two-stage exhaust gas cooler with a first cooling stage and with a second cooling stage, with at least one bypass for bypassing the first and / or second cooling stage of the exhaust gas cooler and with at least one exhaust gas control valve, At least a first intercooler and a bypass for bypassing the first intercooler and with a charge air control valve, - At least one temperature sensor for measuring the exhaust gas and / or charge air temperature With a control unit for controlling the exhaust gas mass flow through the first and / or the second cooling stage of the exhaust gas cooler and / or for controlling the mass flow through the bypass to bypass the first and / or second cooling stage of the exhaust gas cooler and / or for controlling the charge air mass flow through the first charge air cooler and / or for controlling the mass flow through the bypass to bypass the first charge air cooler to avoid condensation in the exhaust gas cooler and / or in the first charge air cooler, wherein the Agbasmassenstrom and / or the charge air mass flow in dependence on the temperature of the exhaust gas stream and / or the charge air temperature such is controlled that essentially no condensate is generated. A method according to claim 8, characterized in that further by means of a heater in the bypass of the first charge air cooler, the passed charge air is controlled heated to avoid condensation. A method according to claim 8 or 9, characterized in that by means of a first valve and / or a second valve, a control of the exhaust gas mass flow is controlled by the first and / or by the second cooling stage of the exhaust gas cooler and / or by a bypass for bypassing the first and or second cooling stage of the exhaust gas cooler or by a bypass for bypassing the first cooling stage of the exhaust gas cooler. Method according to one of claims 8 to 10, characterized in that means of a third valve, a control of the charge air mass flow through the first charge air cooler and / or a control of the charge air mass flow through a bypass to bypass the first charge air cooler. Method according to one of claims 8 to 11, characterized in that by means of a fourth valve, a control of the coolant mass flow takes place through the first charge air cooler.

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