KR101978254B1 - Intake manifold temperature control device and methods for Exhaust Gas Recirculation system - Google Patents

Abstract

Disclosed is a temperature control device for an intake manifold to prevent generation of a condensate caused by a temperature difference between exhaust gas recirculation (EGR) gas and combustion fresh air in an intake manifold of an internal combustion engine using an EGR system. According to the present invention, the temperature control device for an intake manifold comprises: a thermoelectric device installed to surround all or a part of a surface of an intake manifold connected to a recirculation line which recirculates a part of exhaust gas to an intake side; and a controller using information acquired from sensors of the recirculation and intake lines to predict generation of a condensate in the intake manifold in which the exhaust gas and fresh gas are joined, and controlling the thermoelectric device in accordance with a condensate generation prediction result to control the temperature of the intake manifold.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an intake manifold temperature control device and an exhaust gas recirculation system for an exhaust gas reflux system,

The present invention relates to an apparatus and method for controlling the temperature of an intake manifold for an exhaust gas recirculation system, and more particularly, to an exhaust gas recirculation system (EGR system) The present invention relates to an apparatus and method for controlling the temperature of an intake manifold for an exhaust gas reflux system.

Nitrogen oxides (NOx) are environmental hazards generated by the combination of oxygen and nitrogen in a high-pressure and high-temperature environment. In order to suppress this, some of the exhaust gas to the atmosphere is returned to the intake system to lower the maximum combustion temperature, To reduce the production of nitrogen oxides is generally referred to as an EGR (exhaust gas recirculation) system.

The amount of exhaust gas recirculated to the intake side via the EGR system determines the combustion state of the fuel in the combustion chamber and also has a very important influence on the emission of nitrogen oxides (NOx) and particulate matter (PM). Therefore, it is very important to control the amount of exhaust gas recirculated to the intake side of the engine in exhaust gas recirculation (EGR) technology.

1 is a schematic block diagram of a conventional general EGR system applied to a diesel vehicle.

1, the EGR system 100 includes an exhaust line 122 through which exhaust gas generated in the engine 110 is discharged, an intake line 121 that supplies combustion air to the engine 110, an EGR pipe 131 An EGR valve assembly 140 connected to the exhaust gas discharge line 122 via the EGR valve assembly 140 and an EGR cooler 150 installed in the middle of another EGR pipe 131 connecting the intake line 121 and the EGR valve assembly 140 ) And the like.

The EGR pipe 131 is connected to the inlet and the outlet of the EGR cooler 150. An inlet 151 through which the cooling water of the engine flows is formed at one side thereof and an inlet 151 is formed at the other side of the EGR cooler 150 through the EGR cooler 150 An outlet 152 through which the cooling water having a cooling action is discharged is formed. The EGR valve assembly 140 is operated by an electric signal transmitted from a control unit (ECU) to regulate the amount of exhaust gas recirculated to the intake side.

When the EGR valve assembly 110 is operated to the open side in response to a command from the control unit, the EGR system 100 having such a configuration is configured such that a part of the exhaust gas flowing through the exhaust line 122 flows into the suction line 121 through the EGR pipe 131, And is supplied to the combustion chamber of the engine 110 together with the intake air. At this time, the exhaust gas passing through the EGR pipe 131 is supplied to the combustion chamber while being cooled to a predetermined temperature by the EGR cooler 150.

On the other hand, the general EGR system is set to be limitedly driven according to the current outside temperature. There is some deviation according to the maker, but it is restricted to stop or not to use at about 15 degrees to 20 degrees. The most important reason for limiting the use is the condensation occurring at the point where the reflux exhaust gas (EGR gas) and the fresh air are mixed at a low temperature environment.

When the EGR system is operated in a low-temperature environment, condensate is generated and accumulated at a certain point in the intake manifold where the low-temperature intake gas and the high-temperature exhaust gas meet, due to the temperature difference between the two fluids. Is an incompressible fluid that flows into the engine combustion chamber during running and damages the engine or freezing of the remaining condensed water may cause a fatal problem such as a broken connecting rod.

As described above, the conventional general EGR system limits the use of the EGR system according to the outside temperature. In other words, EGR is limited in a low temperature environment below a certain temperature. Therefore, there is a disadvantage that the utilization range of the system is limited, and there is a problem that a deviation of the actual fuel efficiency is large depending on the outside temperature due to the restriction.

Accordingly, a method has been proposed in which the flow rate of the cooling water passing through the EGR cooler is adjusted according to the outside temperature to regulate the temperature of the reflux exhaust gas. However, it is not easy to accurately and precisely control the temperature of the reflux exhaust gas so as to suppress the generation of condensed water by controlling the flow rate of the cooling water.

Korean Patent Laid-Open Publication No. 2016-0070124 (published on June 06, 2016)

SUMMARY OF THE INVENTION It is an object of the present invention to provide an apparatus and method for controlling the temperature of an intake manifold to prevent the generation of condensed water in an intake manifold in a low temperature environment through temperature control of an intake manifold using a thermoelectric element.

Another object of the present invention is to provide an intake manifold temperature control device and method for maximizing the utilization limit of the EGR system (exhaust gas reflux system) through the optimal intake manifold temperature control suited to the ambient temperature environment .

According to an aspect of the present invention,

An apparatus for preventing the generation of condensed water due to a temperature difference between a reflux exhaust gas (EGR gas) and a fresh air for combustion inside an intake manifold of an internal combustion engine to which an EGR system is applied,

A thermoelectric element provided so as to surround part or all of the surface of the intake manifold to which a reflux line for refluxing a part of the exhaust gas to the intake side is connected; And

It is possible to predict the generation of condensed water in the intake manifold where the exhaust gas and the intake air are combined using the information obtained from the sensors of the reflux line and the intake line and to control the temperature of the intake manifold by controlling the thermoelectric device according to the predicted result of the condensate generation. A temperature control device for an intake manifold for an exhaust gas recirculation system including a controller for controlling the temperature of the intake manifold.

The controller applied to one aspect of the present invention includes an information collecting unit for acquiring information necessary for predicting the generation of condensate from the sensors, a condensate generation prediction unit for predicting the generation of condensate in the intake manifold using the information required for the condensate generation prediction, A target temperature setting unit for setting a target temperature that can prevent the generation of condensed water when the condensed water is expected to be generated according to a result of the condensed water generation prediction by the condensed water generation predictor, And controlling the temperature of the intake manifold and the internal space of the intake manifold by controlling the thermoelectric element with the determined current control value.

The information required for the prediction of the condensed water obtained from the sensors may include at least one of a relative humidity and a flow rate of fresh air, a temperature and a flow rate and a temperature of a reflux exhaust gas (EGR gas), an internal temperature of an intake manifold, And may include some or all of the pressure information.

Here, the condensed water production predicting unit predicts the generation of the condensed water by comparing the information required for the condensed water production prediction with the information of the saturated steam map stored in the form of data in the change of the saturated steam pressure according to the temperature change of the intake manifold.

Preferably, the condensed water production predicting unit calculates the steam pressure of the mixed gas (intake air + exhaust gas) from the information required for the condensed water generation prediction, and determines the calculated steam pressure by the saturated steam map according to the temperature of the intake manifold The generation of condensed water can be predicted in comparison with the saturated water vapor pressure inside the intake manifold.

At this time, it can be predicted that when the water vapor pressure of the mixed gas exceeds the saturated water vapor pressure in the intake manifold determined by the saturated water vapor map, condensed water is generated.

Also, the target temperature setting unit may use the non-condensed temperature data derived through simulation or repeated experiment based on the temperature deviation between the fresh air and the reflux exhaust gas (EGR gas) and the pressure value of the intake manifold The target temperature can be set.

Further, the controller applied to one aspect of the present invention controls the temperature of the intake air by raising the temperature of the intake manifold through the thermoelectric element at a temperature range during which the operation of the exhaust gas recirculation system is restricted, Can be performed.

In addition, when the temperature rise control for the intake manifold is unnecessary or the temperature of the intake manifold needs to be lowered according to the driving situation, the controller may cool the intake manifold through the thermoelectric element to generate fresh air, May be performed.

According to another aspect of the present invention as a solution to the problem,

A method for preventing the generation of condensed water due to a temperature difference between a reflux exhaust gas (EGR gas) and a fresh air for combustion in an intake manifold of an internal combustion engine to which an EGR system is applied,

An information collecting step of acquiring information necessary for prediction of condensate generation from sensors of the reflux line and the inspiration line;

A condensation water generation prediction step of predicting the generation of condensation water in the intake manifold using the information necessary for the condensation generation prediction;

A target temperature setting step of setting a target temperature that can prevent generation of condensed water when it is expected that condensed water will be generated according to the predicted result of condensate generation;

And a temperature control step of determining a current control value corresponding to the set target temperature and controlling the thermoelectric elements attached to the surface of the intake manifold with the determined current control value to control the temperature of the intake manifold and the internal space of the intake manifold A method for controlling the temperature of an intake manifold for a gas reflux system is provided.

Here, the information required for the prediction of the condensed water production obtained from the sensors includes at least one of the relative humidity of the fresh air, the flow rate and temperature of the fresh air, the flow rate and temperature of the EGR gas, the internal temperature of the intake manifold, May be some or all of the pressure information.

Also, in the condensate generation prediction step, the information required for the prediction of the condensed water generation can be predicted by comparing the change of the saturated steam pressure according to the temperature change of the intake manifold with the information of the saturated steam map stored in the form of data.

Preferably, the water vapor pressure of the mixed gas (intake air + exhaust gas) is calculated from the information necessary for the prediction of the generation of the condensed water, and the calculated water vapor pressure is saturated with the saturation steam map determined by the saturated steam map according to the temperature of the intake manifold The generation of condensed water can be predicted as compared with the water vapor pressure.

More preferably, it can be predicted that condensate will be produced if the water vapor pressure of the mixed gas exceeds the saturated water vapor pressure inside the intake manifold determined by the saturated water vapor map.

In addition, in the target temperature setting step, the condensate non-generated temperature data derived through simulation or repeated experiment is used based on the temperature deviation between the fresh air and the reflux exhaust gas (EGR gas) and the pressure value of the intake manifold So that the target temperature can be set.

According to the apparatus and method for controlling the temperature of the intake manifold for the exhaust gas recirculation system according to the present invention, it is possible to prevent the generation of condensed water in the intake manifold in a low temperature environment by controlling the temperature of the intake manifold using the thermoelectric element. It is possible to prevent the problems caused by the condensed water during the operation, for example, the freezing of the condensed water and the damage to the engine.

Further, according to the embodiment of the present invention, it is possible to control the temperature in the intake manifold by controlling the thermoelectric elements based on the information necessary for the prediction of the generation of condensed water, thereby enabling the optimal intake manifold temperature control suited to the ambient temperature environment. Exhaust gas reflux system) can be extended. That is, the problems of the related art related to the utility of the EGR system can be improved.

In addition, by using thermoelectric elements, it is possible to control the heating and cooling of the intake manifold to be suitable for the required environment while minimizing the additional parts required for the improvement of the EGR utilization, and the bidirectional control , It is expected that not only the temperature control of the intake manifold but also the improvement of the intake efficiency by utilizing the high-temperature waste heat (heat energy included in the reflux exhaust gas) can be expected.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic block diagram of a conventional general EGR system applied to a diesel vehicle. FIG.
2 is a conceptual diagram of an apparatus for controlling the temperature of an intake manifold for an exhaust gas recirculation system according to an aspect of the present invention.
Fig. 3 is a schematic configuration diagram schematically showing the configuration of the temperature control device of Fig. 2; Fig.
FIG. 4 is a schematic control flowchart applied to implement a method for controlling the temperature of an intake manifold according to another aspect of the present invention. FIG.
5 is a flow chart that includes a specific control algorithm applied to implement a method of temperature control of an intake manifold according to another aspect of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

In describing the present invention, the terminology used in the following description is used only to describe a specific embodiment and is not intended to limit the present invention. The singular expressions include plural expressions unless the context clearly dictates otherwise.

It is also to be understood that the terms such as " comprises " or " having " in this specification are intended to specify the presence of stated features, integers, But do not preclude the presence or addition of features, numbers, steps, operations, components, parts, or combinations thereof.

Also, the terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another.

In addition, the terms " part, " " unit, " " module, " and the like, which are described in the specification, refer to a unit for processing at least one function or operation, which may be implemented by hardware or software or a combination of hardware and software .

In the following description with reference to the accompanying drawings, the same reference numerals will be given to the same constituent elements, and redundant description of the same constituent elements will be omitted. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

FIG. 2 is a conceptual diagram of an apparatus for controlling the temperature of an intake manifold for an exhaust gas recirculation system according to an aspect of the present invention, and FIG. 3 is a schematic configuration diagram schematically showing the configuration of the temperature control apparatus of FIG.

2 and 3, an apparatus for controlling the temperature of an intake manifold for an exhaust gas recirculation system according to an aspect of the present invention includes an intake manifold 50 in which an EGR system 30 is applied, (10) for applying heat to the intake manifold (50) under the control of the controller (20) to prevent the generation of condensed water due to the temperature difference between the EGR gas and the fresh air, , Thermo Electric module).

The thermoelectric element 10 is preferably a thermoelectric conversion element made of a highly conductive polymer PEDOT: PSS (Poly (3,4-ethylenedioxythiophene)) film and formed on a flexible material such as paper, A part or whole of the surface of the intake manifold 50 to which the reflux line 32 connected to reflux a part of the exhaust gas as a result of combustion to the intake side is connected, As shown in FIG.

The thermoelectric element 10 is operated under the control of the controller 20 as mentioned above. The controller 20 utilizes the information obtained from the sensors 40 to 42 mounted on the reflux line 32 and the intake line 52 to detect the point where the reflux exhaust gas and the intake air join, To predict the generation of condensate in the intake manifold 50 to which the discharge end of the intake manifold 50 is connected. The temperature of the intake manifold 50 is controlled by controlling the thermoelectric element 10 according to the prediction result of the condensed water production.

The controller 20 includes an information collecting unit 22, as in the example of Fig. The information collecting unit 22 acquires information necessary for prediction of the condensed water production from the sensors on the intake line 52 and the reflux line 32. [ The information necessary for the prediction of the condensed water production may include some or all of the information on the relative humidity and flow rate of the intake air, the temperature, the flow rate and temperature of the reflux exhaust gas, and the internal temperature and pressure of the intake manifold 50 .

The information required for the condensate generation prediction by the information collection unit 22 is provided to the condensed water generation predicting unit 24. The condensed water generation predicting unit 24 predicts the generation of condensed water in the intake manifold 50 by using the provided information. Preferably, the provided information is compared with the information of the saturated steam map stored in the recording device to predict the generation of condensed water.

Specifically, the condensed water generation predicting unit 24 calculates the steam pressure of the mixed gas (intake air + reflux exhaust gas) in the intake manifold 50 from the information required for the condensed water generation prediction provided from the information collecting unit 22 And the generated water vapor pressure is compared with the saturated water vapor pressure in the intake manifold 50 determined by the saturated water vapor map according to the temperature information of the intake manifold 50 to predict the generation of the condensed water.

More specifically, it can be predicted that condensed water is generated when the water vapor pressure of the mixed gas calculated from the provided information exceeds the saturated water vapor pressure in the intake manifold 50 determined by the saturated water vapor map. (Condensation water generation) occurs when the water vapor pressure of the mixed gas in the intake manifold 50 exceeds the saturated water vapor pressure in the intake manifold 50 because the water vapor is saturated.

The saturated vapor map may preferably be a map that stores the change of the saturated water vapor pressure in the form of data in accordance with the temperature change of the intake manifold 50. [ Specifically, the average value of the saturated steam pressures in the intake manifold 50 is derived from the repeated experiment or the pre-simulation under the same simulated experimental conditions, and the obtained results are converted into tabular data for the temperature Lt; / RTI >

The predicted result of the condensed water generation by the condensed water generation predicting unit 24 is provided to the target temperature setting unit 26. [ The target temperature setting section 26 sets the target temperature for the intake manifold 50 based on the result of the condensed water generation prediction. Specifically, when the target condensate is expected to be generated as a result of the condensate generation prediction, the target temperature that can prevent the generation of the condensed water is set.

The target temperature setting section 26 sets the target temperature to the minimum temperature that can prevent the generation of condensed water based on the temperature deviation between the current fresh air and the reflux exhaust gas (EGR gas) and the present pressure value of the intake manifold 50 To set the target temperature. As the target temperature setting, a method of utilizing the condensed water non-generated temperature data derived from the repeated experiment or pre-simulation using the temperature deviation and the pressure value as variables may be considered.

For example, the target temperature setting unit 26 sets the saturation water vapor pressure of the current intake manifold 50 from the current non-condensing temperature data to the current mixed gas temperature and the current pressure value of the intake manifold 50, It is possible to find the temperature minimum value that prevents the condensation action from occurring due to the water vapor pressure being higher than the water vapor pressure and provide the detected temperature information (the lowest temperature value without condensation) to the temperature control unit 28 described later.

Of course, in addition to the method of utilizing the map-type information, the flow rate and the temperature deviation of each of the intake air and the reflux exhaust gas, the difference between the pressure value of the intake manifold 50 and the saturated water vapor pressure And a program for automatically calculating and outputting the target temperature when the water vapor pressure and the saturated water vapor pressure are obtained by using the derived relational expression can be considered as well as all practical methods that can be derived.

The target temperature information set by the target temperature setting section 26 is transmitted to the temperature control section 28. [ The temperature control unit 28 determines the current control value of the thermoelectric element 10 corresponding to the set target temperature through the above process. Then, the thermoelectric element 10 is controlled with the determined current control value to perform temperature control on the internal space of the intake manifold 50 and the intake manifold 50.

For example, when the set target temperature T2 is set higher than the temperature T1 of the intake manifold 50 by the predetermined temperature T3, T3 = T2 - T1, The temperature of the thermoelectric element 10 required for raising the temperature of the thermoelectric element 10 is calculated by using a predetermined relation formula that can be derived from a map or an experiment and the thermoelectric element 10 is controlled by the obtained current control value, ) Is increased by T3.

On the other hand, the controller 20 applies heat to the intake manifold 50 in a temperature range during which the driving of the exhaust gas recirculation system is restricted, such as an exceptional period outside the temperature range that can prevent the generation of condensed water, The temperature of the fresh air may be raised to a temperature suitable for emission reduction to control the thermoelectric element 10 to exhibit the emission reduction effect.

In some cases, the temperature rise control for the intake manifold 50 may not be necessary, or the temperature of the intake manifold 50 may need to be lowered. This is the case in which the torque priority control is required in the vehicle starting state. In this case, the controller 20 may control the thermoelectric element 10 to reverse the temperature of the fresh air by cooling the intake manifold 50 by the endothermic action.

Hereinafter, a temperature control process performed by the temperature control apparatus for an intake manifold for an exhaust gas recirculation system according to one aspect will be described with reference to a flowchart.

FIG. 4 and FIG. 5 are flowcharts each including a schematic control flowchart and a specific control algorithm applied to implement the method of controlling the temperature of the intake manifold according to another aspect of the present invention.

4 to 5, a method for controlling an intake manifold according to another aspect of the present invention includes an information collecting step of collecting information necessary for prediction of condensate generation, a condensate generation prediction A target temperature setting step of setting a target temperature from the predicted result of condensation generation, and a temperature control step of the final intake manifold.

First, it is determined whether the temperature of the present outside air belongs to a temperature zone that can prevent the generation of condensed water (S50). In other words, it is first determined whether the temperature of the present outdoor air is in a temperature range suitable for driving the EGR system. If the temperature of the outside air is too low, the generation of condensed water can not be effectively suppressed even by the temperature control on the intake manifold.

As a result of the determination of the outside air temperature, if it is determined that the temperature is within the temperature range for preventing the generation of condensed water, the following process is performed. Specifically, if it is determined that the outdoor air temperature is within the temperature range that can prevent the generation of condensed water, the flow proceeds to the information collection step S100.

In the information collection step S100, information necessary for prediction of the condensed water production is obtained from the sensors on the intake line and the return line. The information necessary for predicting the condensation generation may include some or all of the information on the relative humidity and flow rate of the intake air, the temperature and the flow rate and temperature of the reflux exhaust gas, and the internal temperature and pressure of the intake manifold as the confluent part .

The information necessary for the prediction of the condensed water collected in the information collection step (S100) is utilized in the condensed water generation prediction in the condensed water generating step (S200). In the prediction step (S200) of condensate generation, the generation of condensed water in the intake manifold is predicted from information necessary for prediction of condensate generation. Preferably, the provided information is compared with information in the saturated vapor map previously stored in the recording device to predict the generation of condensed water.

Specifically, in the condensation water production predicting step S200, the water vapor pressure of the mixed gas (intake air + reflux exhaust gas) in the intake manifold is calculated from the information necessary for the condensation generation prediction, and the calculated water vapor pressure is stored in the temperature information of the intake manifold The generation of condensed water can be predicted in comparison with the saturated water vapor pressure inside the intake manifold determined by the saturated water vapor map.

Preferably, the condensed water is generated when the water vapor pressure of the mixed gas calculated from the provided information exceeds the saturated water vapor pressure in the intake manifold determined by the saturated water vapor map. If the water vapor pressure of the mixed gas in the intake manifold exceeds the saturated water vapor pressure in the intake manifold, the water vapor saturates and condensation (condensation) occurs.

If it is predicted that the condensed water will be generated (S210), the process proceeds to the target temperature setting step S300, which is the next step. In the target temperature setting step (S300), the target temperature for the intake manifold is set based on the result of the condensed water generation prediction. Specifically, when the target condensate is expected to be generated as a result of the prediction of the generation of the condensed water, a target temperature capable of preventing the generation of the condensed water is set.

In the target temperature setting step S300, the minimum value of the temperature values that can prevent the generation of condensed water based on the temperature deviation between the present fresh air and the reflux exhaust gas (EGR gas) and the present pressure value of the intake manifold An algorithm for setting the target temperature may be used. For the target temperature setting, it is possible to consider a method that utilizes the result of the repeated experiment using the temperature deviation and the pressure value as variables, and the result of condensation non-generated temperature data obtained through the simulation.

For example, if the current mixed gas temperature and the current pressure value of the intake manifold are taken as the lowest value among the temperature values for preventing the condensation action from occurring by increasing the saturated steam pressure of the present intake manifold higher than the water vapor pressure of the present mixed gas from the non- And finds the detected temperature information (the lowest temperature value without condensation) to be utilized in the temperature control step described later.

Of course, in addition to the method of utilizing the map-type information, the flow rate and the temperature deviation of each of the intake air and the reflux exhaust gas, the pressure difference of the intake manifold, and the saturated water vapor pressure, And a program for automatically calculating and outputting the target temperature when the water vapor pressure and the saturated water vapor pressure are obtained by using the derived relational expression, and all practical methods can be considered.

The target temperature information set in the target temperature setting step S300 is used as important information for the temperature control in the temperature control step S400. In the temperature control step S400, a thermoelectric current control value corresponding to the set target temperature is determined through the above process. Then, the thermoelectric element is controlled by the determined current control value to perform temperature control for the intake manifold and the intake manifold internal space.

For example, when the set target temperature T2 is set to be higher by a predetermined temperature (T3, T3 = T2 - T1) with respect to the temperature T1 of the intake manifold, the temperature of the intake manifold is increased by the set temperature value T3 Control can be performed by obtaining a current control value of the thermoelectric element necessary for raising the temperature of the intake manifold by using a map or a predetermined relational expression, controlling the thermoelectric element by the obtained current control value, and raising the temperature of the intake manifold by T3.

Next, it is determined whether the intake manifold reaches the target temperature by temperature control for the intake manifold through the thermoelectric element (S410) with information fed back from a thermoelectric element or a sensor (for example, a temperature monitoring sensor installed in the intake manifold) When it is determined that the target temperature has been reached, the temperature control process for the intake manifold is terminated. Otherwise, the temperature of the intake manifold is controlled by continuously controlling the thermoelectric device.

On the other hand, in a temperature range during which the operation of the exhaust gas recirculation system is restricted, such as an exceptional period outside the temperature range in which condensate generation can be prevented, for example, a cold start, heat is applied to the intake manifold, The temperature of the thermoelectric element may be raised to a temperature suitable for the reduction of the emission to control the thermoelectric element to exhibit the emission reduction effect (S500).

In some cases, the temperature rise control for the intake manifold may not be necessary or the temperature of the intake manifold may need to be lowered. This is the case in which the torque priority control is required in the vehicle starting state. In this case, though not shown, the thermoelectric element may function as an endothermic function in reverse to control cooling of the intake manifold to lower the temperature of the fresh air.

According to the embodiments of the present invention described above, it is possible to prevent the generation of condensed water in the intake manifold in a low temperature environment by controlling the temperature of the intake manifold using the thermoelectric element. Accordingly, it is possible to reliably prevent a problem caused by the condensed water when the EGR system is driven, for example, a problem of lethal damage to the engine due to freezing of the condensed water.

Further, by controlling the temperature of the intake manifold using the thermoelectric element, it is possible to use the EGR system without significantly affecting the outside temperature even in a low temperature environment. In other words, the range of use of the EGR system (exhaust gas reflux system), which was limited according to the outside temperature, can be extended and the fuel efficiency improvement effect can be expected.

In addition, by using thermoelectric elements, it is possible to control the heating and cooling of the intake manifold to be suitable for the required environment while minimizing the additional parts required for the improvement of the EGR utilization, and the bidirectional control , It is expected that not only the temperature control of the intake manifold but also the improvement of the intake efficiency by utilizing the high-temperature waste heat (heat energy included in the reflux exhaust gas) can be expected.

In the foregoing detailed description of the present invention, only specific embodiments thereof have been described. It is to be understood, however, that the invention is not to be limited to the specific forms thereof, which are to be considered as being limited to the specific embodiments, but on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims. .

10: thermoelectric element
20: Controller
22: Information collecting section
24: Condensate generation determination unit
26: target temperature setting unit
28:
30: EGR system
32: reflux line
40 ~ 42: Sensor
50: intake manifold
52: Intake line

Claims (15)

An apparatus for preventing the generation of condensed water due to a temperature difference between a reflux exhaust gas (EGR gas) and a fresh air for combustion inside an intake manifold of an internal combustion engine to which an EGR system is applied,
A thermoelectric element provided so as to surround part or all of the surface of the intake manifold to which a reflux line for refluxing a part of the exhaust gas to the intake side is connected; a sensor provided in each of the reflux line and the intake line; And a controller for controlling the temperature of the intake manifold by controlling the thermoelectric element according to a result of the prediction of the generation of condensed water, wherein the controller controls the temperature of the intake manifold,
The controller includes:
An information collecting unit for acquiring information required for prediction of condensate generation from the sensors;
A condensation water generation predicting unit for predicting the generation of condensation water in the intake manifold using the information necessary for the prediction of the condensation generation and the saturated water vapor map;
A target temperature setting unit for setting a target temperature that can prevent the generation of condensed water when it is expected that condensed water will be generated according to a result of the condensed water generation prediction by the condensed water generation predictor;
And a temperature control unit for determining a current control value corresponding to the set target temperature and controlling the temperature of the intake manifold and the internal space of the intake manifold by controlling the thermoelectric element with the determined current control value, Temperature control device of manifolds.
delete The method according to claim 1,
The information required for the condensate generation prediction, which is obtained from the sensors,
An exhaust gas recirculation system including a part or all of information on the relative humidity of the fresh air, the flow rate and temperature of the fresh air, the flow rate and temperature of the EGR gas, and the internal temperature and pressure of the intake manifold, Temperature control device for intake manifold.
The method according to claim 1,
The condensed water production predicting unit predicts,
A temperature control device for an intake manifold for an exhaust gas recirculation system for predicting the generation of condensed water by comparing the information required for the prediction of the condensed water production with the information of the saturated steam map stored in the form of data in accordance with the change in the saturated steam pressure according to the temperature change of the intake manifold .
5. The method of claim 4,
The condensed water production predicting unit predicts,
The steam pressure of the mixed gas (intake air + exhaust gas) is calculated from the information required for the condensed water production prediction, and the calculated steam pressure is compared with the saturated steam pressure inside the intake manifold determined by the saturated steam map according to the temperature of the intake manifold An apparatus for controlling the temperature of an intake manifold for an exhaust gas reflux system which predicts the generation of condensed water.
6. The method of claim 5,
And estimates that condensed water is generated when the water vapor pressure of the mixed gas exceeds a saturated water vapor pressure inside the intake manifold determined by the saturated water vapor map.
The method according to claim 1,
Wherein the target temperature setting unit includes:
Exhaust gas setting the target temperature using the condensate non-generating temperature data derived through simulation or repeated experiment based on the temperature deviation between the fresh air and the reflux exhaust gas (EGR gas) and the pressure value of the intake manifold Temperature control device for intake manifold for reflux system.
The method according to claim 1,
The controller includes:
Temperature control of an intake manifold for an exhaust gas recirculation system that performs control to increase the temperature of fresh air by heating the intake manifold through the thermoelectric element at a temperature range during which the operation of the exhaust gas recirculation system is restricted Device.
The method according to claim 1,
The controller includes:
If the temperature rise control for the intake manifold is not required or the temperature of the intake manifold needs to be lowered according to the driving situation, the temperature of the intake air is lowered by cooling the intake manifold through the thermoelectric element Temperature control device for an intake manifold for an exhaust gas reflux system that performs control.
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