Condensate water leading-out device for EGR system and control method of condensate water leading-out device

Abstract

The invention relates to the technical field of engines, and discloses a condensate water leading-out device for an EGR system and a control method thereof.The leading-out device comprises a condensate water separation structure, a water storage tank, a first water valve, a second water valve, a second water valve and a third water valve, and the condensate water separation structure is arranged between an intercooler and an intake manifold of an engine; the first water valve is arranged between the condensate water separation structure and the water storage tank, the second water valve is arranged at a drainage pipeline of the water storage tank, and the controller is used for controlling the first water valve and the second water valve according to the rotating speed and the load of the engine and the working state of the EGR system so that the first water valve and the second water valve can be opened; or the first water valve is opened and the second water valve is closed; or the first water valve is closed and the second water valve is opened. According to the leading-out device, condensate water flowing into an engine cylinder can be reduced, the problem of unstable combustion or fire of an engine is solved, and the reliability and fuel economy of the engine are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of engines, and in particular to a condensed water extraction device for an EGR system and a control method for the condensed water extraction device for the EGR system. Background Art

[0002] The Exhaust Gas Recirculation (EGR) system can reintroduce the exhaust gas discharged by the engine into the intake pipe, and after mixing with the fresh air in the mixer, it enters the cylinder and participates in the combustion process again to reduce the engine's knock tendency, increase the compression ratio, and reduce engine fuel consumption.

[0003] After the engine uses the low-pressure EGR system, the exhaust gas will be mixed with fresh air, and the mixed gas will flow through the supercharger and then into the intercooler. After the intercooler cools the mixed gas, a lot of condensed water will be formed. The condensed water enters the engine cylinder along the intake manifold, which will cause unstable combustion or misfire in the cylinder, affecting engine reliability and fuel economy. Summary of the invention

[0004] The present invention aims to solve at least one of the related technical problems to a certain extent. To this end, the first purpose of the present invention is to propose a condensate extraction device for an EGR system, in which a condensate separation structure is provided behind an intercooler, so that the water vapor mixture flowing out of the intercooler passes through the condensate separation structure, and part of the condensate flowing out of the intercooler is collected and discharged through a water valve, which can reduce the condensate flowing into the engine cylinder, improve the problem of unstable combustion or misfire of the engine, and improve the reliability and fuel economy of the engine.

[0005] A second objective of the present invention is to provide a control method for a condensate discharge device of an EGR system.

[0006] To achieve the above-mentioned objectives, an embodiment of the first aspect of the present invention proposes a condensate extraction device for an EGR system, comprising: a condensate separation structure, the condensate separation structure is arranged between the intercooler and the intake manifold of the engine, and is used to extract the condensate in the water-gas mixture discharged from the intercooler; a water storage tank, the water storage tank is used to store the condensate extracted by the condensate separation structure; a first water valve, the first water valve is arranged between the condensate separation structure and the water storage tank, and is used to control the selective connection between the condensate separation structure and the water storage tank; a second water valve, the second water valve is arranged at the drainage pipe of the water storage tank, and is used to control the discharge of the condensate stored in the water storage tank; a controller, the controller is used to control the first water valve and the second water valve according to the engine speed, load and working state of the EGR system, so that the first water valve and the second water valve are opened; or the first water valve is opened and the second water valve is closed; or the first water valve is closed and the second water valve is opened.

[0007] In addition, the condensate extraction device for the EGR system according to the above embodiment of the present invention may also have the following additional technical features:

[0008] According to some embodiments of the present invention, the condensed water separation structure includes an inlet pipe, an outlet pipe and a water storage chamber; the inlet pipe is connected to the outlet of the engine's intercooler; the outlet pipe is connected to the inlet of the engine's intake manifold; the water storage chamber is arranged between the inlet pipe and the outlet pipe to seal the interface between the inlet pipe and the outlet pipe.

[0009] According to some embodiments of the present invention, the position of the pipe opening of the air inlet pipe in the direction of gravity is higher than the position of the pipe opening of the air outlet pipe in the direction of gravity.

[0010] According to some embodiments of the present invention, a water outlet is provided at the bottom of the water storage chamber, and the water outlet is used to lead the condensed water collected in the water storage chamber to the water storage tank through a discharge pipe.

[0011] According to some embodiments of the present invention, a secondary collection area is provided at the bottom of the air outlet pipe near the water storage chamber, and the secondary collection area is filled with absorbent material. The absorbent material is used to collect condensed water flowing through the air outlet pipe. The secondary collection area is connected to the discharge pipe, and the condensed water collected by the absorbent material flows into the discharge pipe under the action of gravity.

[0012] According to some embodiments of the present invention, the first water valve and the second water valve are provided with position sensors, and the position sensors are used to send an alarm signal to the controller when the first water valve and / or the second water valve is not closed tightly and / or is stuck.

[0013] According to an embodiment of the present invention, a condensate extraction device for an EGR system includes: a condensate separation structure, which is arranged between an intercooler and an intake manifold of an engine, and is used to extract condensate from a water-gas mixture discharged from the intercooler; a water storage tank, which is used to store condensate extracted by the condensate separation structure; a first water valve, which is arranged between the condensate separation structure and the water storage tank, and is used to control the selective connection between the condensate separation structure and the water storage tank; a second water valve, which is arranged at a drainage pipe of the water storage tank, and is used to control the discharge of condensate stored in the water storage tank; and a controller, which is used to control the first water valve and the second water valve according to the engine speed, load and working state of the EGR system, so that the first water valve and the second water valve are opened; or the first water valve is opened and the second water valve is closed; or the first water valve is closed and the second water valve is opened. Therefore, the present extraction device is provided with a condensed water separation structure behind the intercooler, so that the water vapor mixture flowing out of the intercooler passes through the condensed water separation structure, and part of the condensed water flowing out of the intercooler is collected and discharged through a water valve. This can reduce the condensed water flowing into the engine cylinder, improve the problem of unstable combustion or misfire of the engine, and enhance the reliability and fuel economy of the engine.

[0014] The second purpose of the present invention is to propose a control method for the condensate extraction device of the EGR system, which controls the opening or closing of the water valve according to the engine speed, load and working state of the EGR system, thereby reducing the condensate flowing into the engine cylinder, improving the problem of unstable combustion or misfire of the engine, and improving the reliability and fuel economy of the engine.

[0015] To achieve the above-mentioned purpose, the second aspect of the embodiment of the present invention proposes a control method for a condensate extraction device of an EGR system, including: obtaining the engine speed, load and working state of the EGR system; determining whether the working state of the engine is zero and whether the working state of the EGR system is not started; controlling the first water valve and the second water valve to open or close.

[0016] In addition, the control method for the condensate extraction device of the EGR system according to the above embodiment of the present invention may also have the following additional technical features:

[0017] According to some embodiments of the present invention, the above-mentioned control method for the condensate extraction device of the EGR system also includes: in response to the engine speed and the engine load being not zero and the working state of the EGR system being an unstarted state, controlling the first water valve and the second water valve to be opened in turn according to a first preset time interval to extract the condensate in the water-gas mixture discharged from the intercooler through the condensate separation structure and the water storage tank in turn.

[0018] According to some embodiments of the present invention, the above-mentioned control method for the condensate extraction device of the EGR system also includes: in response to the engine speed and the engine load being not zero and the working state of the EGR system being not an unstarted state, determining whether the working state of the EGR system is working according to a preset working condition; in response to the working state of the EGR system being working according to a preset working condition, controlling the first water valve and the second water valve to open in turn according to the preset working condition and a second preset time interval, so as to extract the condensate in the water-gas mixture discharged from the intercooler through the condensate separation structure and the water storage tank in sequence; wherein, the preset working condition corresponds to the second preset time interval.

[0019] According to some embodiments of the present invention, the above-mentioned control method for the condensate extraction device of the EGR system further includes: in response to the engine being shut down, controlling the first water valve and the second water valve to open.

[0020] According to an embodiment of the present invention, a control method for a condensate outlet device of an EGR system is applied to a controller of a condensate outlet device of an EGR system, and includes: obtaining the engine speed, load, and working state of the EGR system; determining whether the working state of the engine is zero and whether the working state of the EGR system is not started; and controlling the first water valve and the second water valve to open or close. Thus, the method controls the water valve to open or close according to the engine speed, load, and working state of the EGR system, which can reduce the condensate flowing into the engine cylinder, improve the problem of unstable combustion or misfire of the engine, and improve the reliability and fuel economy of the engine.

[0021] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of a condensed water extraction device for an EGR system according to some embodiments of the present invention;

[0023] Figure 2 is a schematic diagram of the interior of a condensed water separation structure according to some embodiments of the present invention;

[0024] Figure 3 A schematic diagram of the interior of a water storage chamber and an air outlet pipe according to some embodiments of the present invention;

[0025] Figure 4 The present invention is a flowchart of a control method for a condensate discharge device of an EGR system according to some embodiments of the present invention.

[0026] Description of Reference Numerals

[0027] 1-EGR system, 2a-turbocharger turbine, 2b-supercharger compressor, 3-intercooler, 4-condensed water separation structure, 41-intake pipe, 42-water storage chamber, 421-water outlet, 422-wall of water storage chamber, 43-outlet pipe, 431-secondary collection area, 432-water absorbing material, 433-outlet pipe inlet, 434-secondary collection area outlet, 5-first water valve, 6-water storage tank, 7-second water valve, 8-intake manifold, 9-combustion chamber, 10-exhaust pipe. DETAILED DESCRIPTION

[0028] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0029] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the embodiments of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0030] As mentioned in the background technology section, the exhaust gas recirculation system can reintroduce the exhaust gas discharged by the engine into the intake pipe, and after mixing with the fresh air in the mixer, it enters the cylinder and participates in the combustion process again to reduce the emission of nitrogen oxides from the engine.

[0031] In the process of realizing the present invention, the applicant discovered that after the engine uses a low-pressure EGR system, since nearly one-third of the mass of the engine's exhaust gas is water vapor, the exhaust gas will be mixed with fresh air, and the mixed gas will flow through the supercharger and then into the intercooler. After the intercooler cools the mixed gas, a large amount of condensed water will be formed. The condensed water enters the engine cylinder along the intake manifold, which will cause unstable combustion or misfire in the cylinder, affecting the engine reliability and fuel economy.

[0032] The following describes a condensed water outlet device for an EGR system and a control method for the condensed water outlet device for an EGR system, which are provided in embodiments of the present invention, with reference to the accompanying drawings.

[0033] refer to Figure 1 , is a schematic diagram of a condensate extraction device for an EGR system according to some embodiments of the present invention.

[0034] The condensate extraction device for the EGR system of the present invention comprises a condensate separation structure 4, a water storage tank 6, a first water valve 5, a second water valve 7, and a controller (not shown in the figure).

[0035] The exhaust gas in the EGR system 1 will be mixed with fresh air, and the mixed gas will flow through the supercharger and then into the intercooler 3. After the intercooler 3 cools the mixed gas, a lot of condensed water will be formed. Since the condensed water separation structure 4 is arranged between the intercooler 3 and the intake manifold 8 of the engine, a part of the water-vapor mixture flowing out of the intercooler 3 will flow into the condensed water separation structure 4, and be blocked and collected by the water separation structure, so that the condensed water separation structure 4 can lead out the condensed water in the water-vapor mixture discharged from the intercooler 3; the other part of the water-vapor mixture can flow smoothly through the water separation structure and enter the engine cylinder along the intake manifold 8, thereby reducing the condensed water flowing into the engine cylinder, improving the problem of unstable combustion or misfire of the engine, and improving the reliability and fuel economy of the engine.

[0036] refer to Figure 2 , is a schematic diagram of the interior of a condensate separation structure according to some embodiments of the present invention. The condensate separation structure 4 includes an air inlet pipe 41, an air outlet pipe 43 and a water storage chamber 42.

[0037] The intake pipe 41 is connected to the outlet of the engine's intercooler 3 to receive the water vapor mixture flowing out of the intercooler 3. The outlet pipe 43 is connected to the inlet of the engine's intake manifold 8 to allow the water vapor mixture to enter the engine cylinder along the intake manifold 8. The water storage chamber 42 is sleeved between the intake pipe 41 and the outlet pipe 43 to seal the interface between the intake pipe 41 and the outlet pipe 43.

[0038] The position of the pipe opening of the air inlet pipe 41 in the direction of gravity is higher than the position of the pipe opening of the air outlet pipe 43 in the direction of gravity, which helps to separate and discharge the condensed water flowing out of the intercooler 3 .

[0039] A water outlet 421 is provided at the bottom of the water storage chamber 42 , wherein the diameter of the water outlet 421 may be smaller than the diameter of the water storage chamber 42 , and the water outlet 421 leads the condensed water collected in the water storage chamber 42 to the water storage tank 6 through a discharge pipe.

[0040] A secondary collection area 431 is provided at the bottom of the air outlet pipe 43 near the water storage chamber 42. The secondary collection area 431 is filled with a water-absorbing material 432. For example, the water-absorbing material 432 may be a sponge. The water-absorbing material 432 collects condensed water flowing through the air outlet pipe 43. The secondary collection area 431 is connected to the discharge pipe. The condensed water collected by the water-absorbing material 432 flows into the discharge pipe under the action of gravity and is led out to the water storage tank 6.

[0041] After a portion of the water vapor mixture flowing out of the intercooler 3 flows into the condensed water separation structure 4 , the water storage tank 6 stores the condensed water drawn out of the condensed water separation structure 4 .

[0042] The first water valve 5 is arranged between the condensed water separation structure 4 and the water storage tank 6. For example, the first water valve 5 can be a solenoid valve. The first water valve 5 can control the selective connection between the condensed water separation structure 4 and the water storage tank 6. When the condensed water of the condensed water separation structure 4 needs to be discharged, the first water valve 5 is opened (default state) so that the condensed water collected by the condensed water separation structure 4 will flow into the first water valve 5 along the pipeline; when the condensed water of the condensed water separation structure 4 does not need to be discharged, the first water valve 5 is closed.

[0043] The second water valve 7 is arranged at the drainage pipe of the water tank 6. For example, the second water valve 7 can be a solenoid valve. The second water valve 7 controls whether the condensed water stored in the water tank 6 needs to be discharged. When the condensed water stored in the water tank 6 needs to be discharged, the first water valve 5 is closed and the second water valve 7 is opened; when the condensed water stored in the water tank 6 does not need to be discharged, the second water valve 7 is closed (default state).

[0044] It should be explained that the working states of the first water valve 5 and the second water valve 7 are divided into two states: closed and open. The first water valve 5 is a normally open valve, which is normally open when no power is supplied, and closed when power is supplied; the second water valve 7 is a normally closed valve, which is normally closed when no power is supplied, and open when power is supplied.

[0045] Position sensors are respectively provided on the first water valve 5 and the second water valve 7. The position of the valve is determined by measuring the displacement of the valve core or the push rod. If the first water valve 5 and / or the second water valve 7 is not tightly closed and / or is stuck, the displacement of the valve core will be significantly different from the normal position. When the position sensor detects that the first water valve 5 and / or the second water valve 7 is not tightly closed and / or is stuck, the position sensor will send the condition of the water valve to the on-board automatic diagnostic system, the on-board automatic diagnostic system will perform diagnosis and send an alarm signal to the controller. When receiving the alarm signal, the controller will display the condition of the first water valve 5 and / or the second water valve 7 being not tightly closed and / or being stuck on the display screen, so that the staff can find the fault in time and perform repairs.

[0046] The controller controls the first water valve 5 and the second water valve 7 according to the engine speed, load and working state of the EGR system 1, so that the first water valve 5 and the second water valve 7 are opened. Alternatively, the controller controls the first water valve 5 to be opened and the second water valve 7 to be closed, so that the condensed water collected by the condensed water separation structure 4 can flow into the water storage tank 6 through the first water valve 5. Alternatively, the controller controls the first water valve 5 to be closed and the second water valve 7 to be opened, so that the condensed water collected in the water storage tank 6 can be discharged through the second water valve 7.

[0047] In some embodiments, reference Figure 3, is a schematic diagram of the inside of the water storage chamber and the air outlet pipe according to some embodiments of the present invention. The water vapor mixture flowing out of the intercooler 3 will flow into the air inlet pipe 41. Most of the larger condensed water droplets in the water vapor mixture will flow along the pipe wall of the air inlet pipe 41. The smaller condensed water droplets and water vapor in the water vapor mixture will flow along the middle of the air inlet pipe 41. When the larger condensed water droplets flow out of the air inlet pipe 41 along the pipe wall of the air inlet pipe 41 along with the water vapor mixture, due to the effect of inertia, some of the water droplets will fly to the outer wall of the air outlet pipe 43 and enter the water storage chamber 42 along the wall surface 422 of the water storage chamber. The other part of the water droplets will flow to the outlet pipe inlet 433 because they are not affected by inertia or do not have time to fall into the water storage chamber 42. Among them, the outlet pipe inlet 433 has the function of guiding the water vapor mixture, so that the water vapor mixture flowing out of the air inlet pipe 41 changes direction in time and flows into the air outlet pipe 43, so as to avoid blowing out the condensed water flowing into the water storage chamber 42 due to inertia.

[0048] The condensed water droplets flow out of the air inlet pipe 41 along with the water vapor mixture, and fall into the water storage chamber 42 under the action of inertia. The condensed water collected in the water storage chamber 42 flows out from the water outlet 421 of the water storage chamber 42 to the first drain valve under the action of gravity. Another part of the condensed water droplets cannot be collected by the water storage chamber 42, and will flow to the secondary collection area 431 in the air outlet pipe 43. A water-absorbing material 432 is arranged below the air outlet pipe 43, and the water-absorbing material 432 can absorb part of the condensed water that flows into the air outlet pipe 43 along with the water vapor mixture. The water-absorbing material 432 is connected to the water storage chamber 42. After the water-absorbing material 432 absorbs condensed water to saturation, the condensed water in the water-absorbing material 432 flows into the water storage chamber 42 through the outlet 434 of the secondary collection area under the action of gravity, and flows to the first drain valve together with the condensed water collected in the water storage chamber 42, and then flows into the water storage tank 6.

[0049] In some embodiments, continue to refer to Figure 1 The engine system of the present invention includes: a combustion chamber 9, an intake manifold 8, an exhaust pipe 10, a turbine 2a of a supercharger, a compressor 2b of a supercharger, an intercooler 3, an EGR system 1, a condensed water separation structure 4, a first water valve 5, a second water valve 7 and a water storage tank 6.

[0050] After the engine uses the EGR system 1, the exhaust gas will be mixed with the fresh air, and the mixed gas will flow through the supercharger (the supercharger includes a turbine 2a and a compressor 2b), and then flow into the intercooler 3. The intercooler 3 will cool the mixed gas to form a water vapor mixture. A part of the water vapor mixture flowing out of the intercooler 3 flows into the condensed water separation structure 4. When the condensed water of the condensed water separation structure 4 needs to be discharged, the first water valve 5 is opened so that the condensed water collected by the condensed water separation structure 4 will flow into the first water valve 5 along the pipeline. The water storage tank 6 will store the condensed water drawn from the condensed water separation structure 4. When the condensed water stored in the water storage tank 6 needs to be discharged, the first water valve 5 is closed and the second water valve 7 is opened. Another part of the water vapor mixture will enter the combustion chamber 9 of the engine along the intake manifold 8, and the exhaust pipe 10 will discharge the exhaust gas generated after the engine combustion out of the vehicle.

[0051] In summary, the condensate extraction device for the EGR system according to an embodiment of the present invention includes: a condensate separation structure, which is arranged between the intercooler and the intake manifold of the engine, and is used to extract the condensate in the water-gas mixture discharged from the intercooler; a water storage tank, which is used to store the condensate extracted by the condensate separation structure; a first water valve, which is arranged between the condensate separation structure and the water storage tank, and is used to control the selective connection between the condensate separation structure and the water storage tank; a second water valve, which is arranged at the drainage pipe of the water storage tank, and is used to control the discharge of the condensate stored in the water storage tank; a controller, which is used to control the first water valve and the second water valve according to the engine speed, load and working state of the EGR system, so that the first water valve and the second water valve are opened; or the first water valve is opened and the second water valve is closed; or the first water valve is closed and the second water valve is opened. Therefore, the present extraction device is provided with a condensed water separation structure behind the intercooler, so that the water vapor mixture flowing out of the intercooler passes through the condensed water separation structure, and part of the condensed water flowing out of the intercooler is collected and discharged through a water valve. This can reduce the condensed water flowing into the engine cylinder, improve the problem of unstable combustion or misfire of the engine, and enhance the reliability and fuel economy of the engine.

[0052] refer to Figure 4 , which is a flow chart of a control method for a condensate extraction device of an EGR system according to some embodiments of the present invention.

[0053] like Figure 4 As shown, the control method for the condensate outlet device of the EGR system according to the embodiment of the present invention may include the following steps:

[0054] S401, obtaining the engine speed, load and working status of the EGR system.

[0055] Specifically, the rotation speed of the engine can be obtained through a crankshaft position sensor disposed on the engine; and the working state of the EGR system can be obtained through a position sensor disposed on the EGR system.

[0056] S402, determining whether the working state of the engine is zero and whether the working state of the EGR system is not started.

[0057] Specifically, after obtaining the engine speed, load and working state of the EGR system, it is determined whether the working state of the engine is zero according to the engine speed and engine load. When the engine speed and engine load are zero, that is, the engine is not running, the working state of the engine is zero at this time; when the engine speed and engine load are not zero, that is, the engine is running, the working state of the engine is not zero at this time. It is determined whether the working state of the EGR system is not started according to the working state of the EGR system. When the EGR system is working, it indicates that the working state of the EGR system is started; when the EGR system is not working, it indicates that the working state of the EGR system is not started.

[0058] S403, controlling the first water valve and the second water valve to open or close.

[0059] Specifically, when the engine speed and the engine load are zero and the working state of the EGR system is not started, it means that the engine is not running, the EGR system is not enabled, no gas flows through the intercooler, no condensed water is generated, and the engine performance is not affected. At this time, the first water valve and the second water valve are not controlled, so that the first water valve is in an open state and the second water valve is in a closed state to reduce energy consumption. When the engine speed and the engine load are not zero and the working state of the EGR system is not started, it means that the engine is running, the EGR system is not enabled, and there is less condensed water in the water-gas mixture discharged from the intercooler. At this time, the first water valve and the second water valve are controlled to be opened in turn at a certain time interval to reduce the condensed water flowing into the engine cylinder.

[0060] In some embodiments of the present invention, the control method for the condensate extraction device of the EGR system further includes: in response to the engine speed and the engine load being not zero and the working state of the EGR system being not started, controlling the first water valve and the second water valve to be opened in turn according to the first preset time interval, so as to extract the condensate in the water-gas mixture discharged from the intercooler through the condensate separation structure and the water storage tank in turn. The first preset time interval can be set according to actual conditions.

[0061] Specifically, when the engine speed and the engine load are not zero and the working state of the EGR system is not started, it means that the engine is running, the EGR system is not enabled, and there is less condensed water in the water-gas mixture discharged from the intercooler. At this time, the first water valve and the second water valve are controlled to open in turn according to the first preset time interval to lead the condensed water in the water-gas mixture discharged from the intercooler through the condensed water separation structure and the water storage tank in turn, thereby reducing the condensed water flowing into the engine cylinder, improving the problem of unstable engine combustion or misfire, and improving the reliability and fuel economy of the engine.

[0062] In some embodiments of the present invention, the above-mentioned control method for the condensate extraction device of the EGR system also includes: in response to the engine speed and the engine load being not zero and the working state of the EGR system being not an unstarted state, determining whether the working state of the EGR system is working according to a preset working condition; in response to the working state of the EGR system being working according to a preset working condition, controlling the first water valve and the second water valve to be opened in turn according to the preset working condition and a second preset time interval, so as to extract the condensate in the water-gas mixture discharged from the intercooler through the condensate separation structure and the water storage tank in turn; wherein, the preset working condition corresponds to the second preset time interval.

[0063] Specifically, when the engine speed and the engine load are not zero and the working state of the EGR system is not the non-started state, it means that the engine is running and the EGR system is enabled. At this time, it is judged whether the working state of the EGR system is working according to the preset working conditions (that is, working according to the EGR MAP). When the working state of the EGR system is working according to the preset working conditions, it means that there is a lot of condensed water in the water-gas mixture discharged from the intercooler. At this time, the first water valve and the second water valve are controlled to open in turn according to the preset working conditions and the second preset time interval, so as to lead the condensed water in the water-gas mixture discharged from the intercooler through the condensed water separation structure and the water storage tank in turn, thereby reducing the condensed water flowing into the engine cylinder, improving the problem of unstable engine combustion or misfire, and improving the reliability and fuel economy of the engine.

[0064] In some embodiments, when the engine speed and the engine load are high, the water-gas mixture discharged from the intercooler contains more condensed water, and the frequency of controlling the opening of the first water valve and the second water valve is higher; when the engine speed and the engine load are low, the water-gas mixture discharged from the intercooler contains less condensed water, and the frequency of controlling the opening of the first water valve and the second water valve is lower.

[0065] In some embodiments of the present invention, the control method for the condensate extraction device of the EGR system further includes: in response to the engine being shut down, controlling the first water valve and the second water valve to open.

[0066] Specifically, when the engine is stopped, in order to reduce the amount of condensed water remaining in the condensed water separation structure, the water storage tank or the second water valve, the self-cleaning mode is performed at this time, and the first water valve and the second water valve are controlled to open to draw out the condensed water in the condensed water separation structure and the water storage tank, so as to avoid problems such as freezing of condensed water or emulsification of engine oil in the condensed water separation structure, the water storage tank or the second water valve.

[0067] In summary, the control method for the condensate outlet device of the EGR system according to the embodiment of the present invention is applied to the controller of the condensate outlet device of the EGR system, including: obtaining the engine speed, load and working state of the EGR system; determining whether the working state of the engine is zero and whether the working state of the EGR system is not started; controlling the first water valve and the second water valve to open or close. Therefore, the method controls the water valve to open or close according to the engine speed, load and working state of the EGR system, which can reduce the condensate flowing into the engine cylinder, improve the problem of unstable combustion or misfire of the engine, and improve the reliability and fuel economy of the engine.

[0068] It should be noted that some embodiments of the present invention are described above. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the above embodiments and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0069] In addition, although the operations of the method of the present invention are described in a specific order in the accompanying drawings, this does not require or imply that the operations must be performed in this specific order, or that all the operations shown must be performed to achieve the desired results. On the contrary, the steps depicted in the flow chart can be performed in a different order. Additionally or alternatively, some steps can be omitted, multiple steps can be combined into one step, and / or one step can be decomposed into multiple steps.

[0070] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the embodiments of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0071] Although the spirit and principle of the present invention have been described with reference to several specific embodiments, it should be understood that the present invention is not limited to the disclosed specific embodiments, and the division of various aspects does not mean that the features in these aspects cannot be combined to benefit, and this division is only for the convenience of expression. The present invention is intended to cover various modifications and equivalent arrangements included in the spirit and scope of the attached claims. The scope of the attached claims conforms to the broadest interpretation, thereby including all such modifications and equivalent structures and functions.

Claims

1. A condensate extraction device for an EGR system, characterized in that: include: A condensed water separation structure (4), the condensed water separation structure (4) being arranged between an intercooler (3) and an intake manifold (8) of the engine and being used for leading out condensed water in the water-gas mixture discharged from the intercooler (3); A water storage tank (6), the water storage tank (6) being used to store condensed water drawn out by the condensed water separation structure (4); a first water valve (5), the first water valve (5) being arranged between the condensed water separation structure (4) and the water storage tank (6) and being used for controlling the selective communication between the condensed water separation structure (4) and the water storage tank (6); a second water valve (7), the second water valve (7) being arranged at a drainage pipe of the water storage tank (6) and being used for controlling the discharge of condensed water stored in the water storage tank (6); A controller is used to control the first water valve (5) and the second water valve (7) according to the engine speed, load and working state of the EGR system (1), so that the first water valve (5) and the second water valve (7) are opened; or the first water valve (5) is opened and the second water valve (7) is closed; or the first water valve (5) is closed and the second water valve (7) is opened.

2. The condensate extraction device for the EGR system according to claim 1, characterized in that: The condensed water separation structure (4) comprises an air inlet pipe (41), an air outlet pipe (43) and a water storage chamber (42); the air inlet pipe (41) is connected to the air outlet of the intercooler (3) of the engine; the air outlet pipe (43) is connected to the inlet of the intake manifold (8) of the engine; the water storage chamber (42) is sleeved between the air inlet pipe (41) and the air outlet pipe (43) so that the interface between the air inlet pipe (41) and the air outlet pipe (43) is sealed.

3. The condensate extraction device for the EGR system according to claim 2, characterized in that: The position at which the pipe opening of the air inlet pipe (41) is arranged in the direction of gravity is higher than the position at which the pipe opening of the air outlet pipe (43) is arranged in the direction of gravity.

4. The condensed water extraction device for the EGR system according to claim 3, characterized in that: The bottom of the water storage chamber (42) is provided with a water outlet (421), and the water outlet (421) is used to lead the condensed water collected in the water storage chamber (42) to the water storage tank (6) through a discharge pipe.

5. The condensed water extraction device for the EGR system according to claim 4, characterized in that: The air outlet pipe (43) is provided with a secondary collection area (431) near the bottom of the water storage chamber (42); the secondary collection area (431) is filled with a water-absorbing material (432); the water-absorbing material (432) is used to collect condensed water flowing through the air outlet pipe (43); the secondary collection area (431) is connected to the discharge pipe; the condensed water collected by the water-absorbing material (432) flows into the discharge pipe under the action of gravity.

6. The condensed water extraction device for the EGR system according to claim 5, characterized in that: The first water valve (5) and the second water valve (7) are provided with position sensors, and the position sensors are used to send an alarm signal to the controller when the first water valve (5) and / or the second water valve (7) are not closed tightly and / or are stuck.

7. A control method for a condensate extraction device of an EGR system, characterized in that: A controller for a condensate extraction device for an EGR system as claimed in any one of claims 1 to 6, comprising: Obtain the engine speed, load and working status of the EGR system; Determine whether the working state of the engine is zero, and whether the working state of the EGR system is an inactive state; Control the first water valve and the second water valve to open or close.

8. The control method for the condensate extraction device of the EGR system according to claim 7, characterized in that: Also includes: In response to the engine speed and the engine load being not zero and the EGR system being in an unstarted state, the first water valve and the second water valve are controlled to be opened in turn at a first preset time interval so that the condensed water in the water-gas mixture discharged from the intercooler is led out through the condensed water separation structure and the water storage tank in turn.

9. The control method for the condensate extraction device of the EGR system according to claim 8, characterized in that: Also includes: In response to the engine speed and the engine load being not zero and the EGR system being in an inactive state, determining whether the EGR system is in an inactive state; In response to the EGR system operating in accordance with a preset operating condition, the first water valve and the second water valve are controlled to be opened in turn according to the preset operating condition and a second preset time interval, so as to lead the condensed water in the water-gas mixture discharged from the intercooler through a condensed water separation structure and a water storage tank in turn; wherein the preset operating condition corresponds to the second preset time interval.

10. The control method for the condensate extraction device of the EGR system according to claim 7, characterized in that: Also includes: In response to the engine being stopped, the first water valve and the second water valve are controlled to be opened.

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