Engine, vehicle and EGR exhaust gas flow control method

Abstract

The invention relates to the technical field of exhaust gas recirculation of engines, in particular to an engine, a vehicle and an EGR exhaust gas flow control method. The engine comprises an air cylinder, at least two exhaust manifold branches, an EGR system and a control system, the air cylinder comprises an air inlet and at least two exhaust ports, the air inlet is communicated with an air inlet manifold, the number of the exhaust manifold branches is the same as that of the exhaust ports, inlets of the exhaust manifold branches are communicated with the exhaust ports in a one-to-one correspondence mode, the EGR system comprises at least two EGR channels, and the EGR channels are communicated with the exhaust ports in a one-to-one correspondence mode. Inlets of the EGR channels communicate with the exhaust manifold branches in a one-to-one correspondence mode, an outlet of each EGR channel communicates with the intake manifold, each EGR channel is connected with the control system, and the control system is used for controlling the waste gas flow of the at least two EGR channels. According to the implementation mode, due to the fact that the opening degree of each EGR channel can be accurately controlled, the engine can achieve optimal EGR rate control under the small exhaust gas flow and the large exhaust gas flow, and therefore the fuel economy and emission consistency of the engine are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of exhaust gas recirculation of an engine, and in particular to an engine, a vehicle and a method for controlling the flow rate of EGR exhaust gas. Background Art

[0002] In the field of internal combustion engines, especially in meeting increasingly stringent emission regulations, exhaust gas recirculation (EGR) technology is widely used to reduce nitrogen oxide (NOx) emissions and improve engine performance. The EGR system guides part of the engine exhaust gas back to the cylinder and mixes it with fresh intake air, thereby reducing combustion temperature and reducing NOx generation. However, in order to ensure the effectiveness of the EGR system, precise control of the EGR flow is essential.

[0003] Traditional EGR systems usually adopt a single-sided pre-turbine intake design, and the EGR valve plate has a larger diameter to cope with high flow requirements. This design can better meet emission requirements at higher EGR flows, but at lower flows, the control accuracy of the EGR flow is poor due to the large size of the valve plate. This imprecise control will lead to large deviations in the EGR rate, which in turn affects the thermal management and emission consistency of the engine. In addition, single-sided intake leads to an unbalanced airflow into the turbine, which reduces turbine efficiency and affects the fuel economy of the engine. Summary of the invention

[0004] The purpose of the present invention is to at least solve the problem of inaccurate EGR exhaust gas flow control caused by single-side air intake. This purpose is achieved through the following technical solutions:

[0005] A first aspect of the present invention provides an engine, comprising:

[0006] A cylinder, wherein the cylinder is provided with an air inlet and at least two exhaust ports, and the air inlet of the cylinder is connected to an intake manifold;

[0007] at least two exhaust manifold branches, the number of the exhaust manifold branches is the same as the number of the exhaust ports, and the inlets of the exhaust manifold branches are connected to the exhaust ports in a one-to-one correspondence;

[0008] An EGR system, the EGR system comprising at least two EGR channels, the inlets of the EGR channels being in one-to-one communication with the exhaust manifold branches, and the outlets of each of the EGR channels being in communication with the intake manifold;

[0009] A control system, each of the EGR channels is connected to the control system, and the control system is used to control the exhaust gas flow of at least two of the EGR channels respectively.

[0010] According to the engine of the present invention, an air inlet and at least two exhaust ports are provided on the cylinder of the engine. The air inlet is connected to an external air source through an intake manifold for inhaling fresh air. At least two exhaust ports are connected to a corresponding number of exhaust manifold branches, and exhaust gas from each exhaust port is discharged through the corresponding exhaust manifold branch. Part of the exhaust gas discharged by the engine is guided to the EGR system through the exhaust manifold branch. The EGR system includes at least two EGR channels, and the inlet of each EGR channel is connected to the corresponding exhaust manifold branch to ensure that each EGR channel only receives exhaust gas discharged from its corresponding exhaust port. The outlet of the EGR channel is connected to the intake manifold so that the treated exhaust gas can flow back to the cylinder and mix with the fresh intake air. Under different working conditions of the engine, the control system can dynamically adjust the opening of each EGR channel to achieve precise control of the exhaust gas flow rate. The engine can achieve optimal EGR rate control under both small and large exhaust gas flows, improve the control accuracy of the EGR exhaust gas flow rate, and thus improve the fuel economy and emission consistency of the engine.

[0011] In addition, the engine according to the present invention may also have the following additional technical features:

[0012] In some embodiments of the present invention, an EGR valve is disposed in each of the EGR passages, and the EGR valve disposed in at least one of the EGR passages is connected to a drive motor.

[0013] In some embodiments of the present invention, the control system includes an electromagnetic clutch, only one of the EGR valves is connected to the drive motor, and the remaining EGR valves are connected to the drive motor via the electromagnetic clutch.

[0014] In some embodiments of the present invention, the EGR system further includes an EGR cooler, outlets of the EGR passages are communicated with an inlet of the EGR cooler, and an outlet of the EGR cooler is communicated with the intake manifold.

[0015] In some embodiments of the present invention, the number of the exhaust ports is two, and the two exhaust ports are opened on opposite sides of the cylinder along the cylinder hole arrangement direction of the cylinder.

[0016] In some embodiments of the present invention, the engine includes a supercharging device, and the outlets of the exhaust manifold branches are all connected to the supercharging device.

[0017] In some embodiments of the present invention, a release valve is provided in the boosting device, and the release valve is used to release the pressure when the gas pressure in the boosting device is too high.

[0018] A second aspect of the present invention provides a vehicle comprising the above-mentioned engine.

[0019] A third aspect of the present invention provides a method for controlling the EGR exhaust gas flow rate, which is implemented according to the above engine and comprises the following steps:

[0020] Obtaining the operating conditions of the engine;

[0021] According to the operating conditions, the EGR demand is obtained by looking up a table;

[0022] According to the EGR demand being within a preset range, the exhaust gas flow rates of at least two of the EGR channels are controlled respectively.

[0023] In some embodiments of the present invention, the step of controlling the exhaust gas flow of at least two of the EGR channels respectively according to the EGR demand being within a preset range comprises:

[0024] If the EGR demand is less than or equal to a set threshold, one of the EGR valves is controlled to be opened, and the other EGR valves are closed, and the opening value of the opened EGR valve is controlled;

[0025] If the EGR demand is greater than a set threshold, at least two of the EGR valves are controlled to open, and the opening values ​​of the opened EGR valves are controlled respectively. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference numerals are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0027] Figure 1 The structure diagram of an engine according to an embodiment of the present invention is schematically shown;

[0028] Figure 2 A flow chart schematically shows a method for controlling the EGR exhaust gas flow rate according to an embodiment of the present invention;

[0029] Figure 3 This is the EGR flow mapping table.

[0030] The reference numerals are as follows:

[0031] 100. Engine;

[0032] 10. Cylinder; 11. Intake manifold;

[0033] 12. Exhaust manifold branch; 121. First branch; 122. Second branch; 13. Exhaust manifold main road;

[0034] 20. Pressurizing device; 21. Air release valve;

[0035] 30. EGR system; 31. First EGR valve; 32. Second EGR valve; 33. Drive motor; 34. Electromagnetic clutch; 35. EGR cooler; 36. Detection parts;

[0036] 40. Post-processing device. DETAILED DESCRIPTION

[0037] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0038] It should be understood that the terms used herein are only for the purpose of describing specific example embodiments and are not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms "one", "an" and "said" as used herein may also be meant to include plural forms. The terms "include", "comprise", "contain", and "have" are inclusive, and therefore specify the existence of stated features, steps, operations, elements and / or parts, but do not exclude the existence or addition of one or more other features, steps, operations, elements, parts, and / or combinations thereof. The method steps, processes, and operations described herein are not interpreted as necessarily requiring them to be performed in the specific order described or illustrated, unless the execution order is clearly indicated. It should also be understood that additional or alternative steps may be used.

[0039] Although the terms first, second, third, etc. can be used in the text to describe multiple elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can only be used to distinguish an element, component, region, layer or section from another region, layer or section. Unless the context clearly indicates, terms such as "first", "second" and other numerical terms do not imply order or sequence when used in the text. Therefore, the first element, component, region, layer or section discussed below can be referred to as the second element, component, region, layer or section without departing from the teaching of the example embodiments.

[0040] For ease of description, spatial relative terms may be used herein to describe the relationship of one element or feature relative to another element or feature as shown in the figure, such as "inside", "outside", "inner side", "outer side", "below", "below", "above", "above", etc. Such spatial relative terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figure. For example, if the device in the figure is turned over, then the elements described as "below other elements or features" or "below other elements or features" will subsequently be oriented as "above other elements or features" or "above other elements or features". Therefore, the example term "below..." can include both above and below orientations.

[0041] like Figure 1 As shown, according to an embodiment of the present invention, an engine 100 is proposed, and the engine 100 (taking a 6-cylinder engine as an example, 6 cylinder holes) includes a cylinder 10, at least two exhaust manifold branches 12, an EGR system 30 and a control system, wherein the cylinder 10 includes an intake port and at least two exhaust ports, the intake port is connected to the intake manifold 11, the exhaust manifold branches 12 are the same in number as the exhaust ports, the inlets of the exhaust manifold branches 12 are connected to the exhaust ports in a one-to-one correspondence, the EGR system 30 includes at least two EGR channels, the inlets of the EGR channels are connected to the exhaust manifold branches 12 in a one-to-one correspondence, the outlets of each EGR channel are connected to the intake manifold 11, and each EGR channel is connected to the control system, and the control system is used to control the exhaust gas flow of at least two EGR channels respectively.

[0042] According to the engine 100 of the present embodiment, an intake port and at least two exhaust ports are provided on the cylinder 10 of the engine 100. The intake port is connected to an external air source through an intake manifold 11 for inhaling fresh air. At least two exhaust ports are connected to a corresponding number of exhaust manifold branches 12, and exhaust gas from each exhaust port is discharged through the corresponding exhaust manifold branch 12. Part of the exhaust gas discharged by the engine 100 is guided to the EGR system 30 through the exhaust manifold branch 12. The EGR system 30 includes at least two EGR channels, and the inlet of each EGR channel is connected to the corresponding exhaust manifold branch 12 to ensure that each EGR channel only receives exhaust gas discharged from its corresponding exhaust port. The outlet of the EGR channel is connected to the intake manifold 11, so that the treated exhaust gas can flow back to the cylinder 10 and mix with the fresh intake air. Under different operating conditions of the engine 100, the control system can dynamically adjust the opening of each EGR channel to achieve accurate control of the exhaust flow rate, thereby optimizing the EGR rate under various operating conditions. By adopting at least two exhaust manifold branches 12 and at least two EGR channels, and each EGR channel is connected to the corresponding exhaust manifold branch 12 in a one-to-one correspondence, this embodiment effectively solves the problem of unbalanced exhaust gas flow caused by unilateral air intake in the traditional EGR system 30. Since each EGR channel is independently connected and controlled by the control system, the control system can adjust the exhaust gas flow of each EGR channel according to the working condition of the engine 100. This design enables the exhaust gas to be evenly distributed to the supercharging device 20 through multiple channels under high EGR flow conditions, thereby balancing the gas flow entering the turbine and avoiding the reduction in efficiency of the turbine due to unbalanced air flow. In addition, since the opening of each EGR channel can be accurately controlled, the engine 100 can achieve optimal EGR rate control under both small and large exhaust gas flows, thereby improving the fuel economy and emission consistency of the engine 100.

[0043] It should be understood that the outlets of the exhaust manifold branch lines 12 are all merged with the exhaust manifold main line 13 to form a complete exhaust pipeline.

[0044] In some embodiments, each EGR channel is provided with an EGR valve, which is installed in the EGR channel and is used to control the exhaust gas flow through the channel. The EGR valve can be an adjustable throttle valve, which can adjust the opening according to instructions to control the amount of exhaust gas entering the intake manifold 11. At least one EGR valve is connected to a drive motor 33, and the drive motor 33 directly controls the opening of the EGR valve through a mechanical connection device (such as a gear, a connecting rod or a screw). The action of the drive motor 33 is driven by the control system instruction, and the opening and closing state of the EGR valve can be adjusted in real time according to the working condition of the engine 100. By setting an EGR valve in each EGR channel and using the drive motor 33 for precise control, the present invention can adjust the EGR flow according to the real-time working condition, which greatly improves the control accuracy of the EGR system 30.

[0045] Furthermore, the control system includes an electromagnetic clutch 34, only one EGR valve is connected to the drive motor 33, and the remaining EGR valves are connected to the drive motor 33 through the electromagnetic clutch 34. Specifically, in the EGR system 30, only one EGR valve is directly connected to the drive motor 33, and the opening of this EGR valve is directly controlled by the drive motor 33, which can quickly respond to the changes in the working conditions of the engine 100. The other EGR valves are indirectly connected to the drive motor 33 through an electromagnetic clutch 34. When the electromagnetic clutch 34 is in a closed state, the power of the drive motor 33 can be transmitted to these EGR valves, thereby adjusting their openings at the same time. When the electromagnetic clutch 34 is in a disconnected state, the remaining EGR valves that are not directly connected to the drive motor 33 are all in a closed state, and no flow passes. When the engine 100 is under low load or low speed conditions such as low flow, the control system disconnects the electromagnetic clutch 34, and at this time the drive motor 33 only controls the opening of the directly connected EGR valve, thereby achieving precise control of small flow exhaust gas. When the engine 100 is under high load or high speed and other high flow conditions, the control system closes the electromagnetic clutch 34. At this time, the power of the drive motor 33 is transmitted to all EGR valves to control their openings to adapt to the larger EGR flow requirements. Through the introduction of the electromagnetic clutch 34, this embodiment can flexibly adjust the control method of multiple EGR valves. Under low flow conditions, the system only uses one EGR valve to achieve fine control. Under high flow conditions, the electromagnetic clutch 34 is closed, and the drive motor 33 synchronously controls multiple EGR valves to ensure sufficient exhaust gas reflow. This not only improves the response speed of the engine 100, but also ensures the best control effect under different working conditions.

[0046] In other embodiments, each EGR valve is connected to a drive motor 33, and the control system is electrically connected to each drive motor 33 to control the opening of each EGR valve. The control system is electrically connected to each drive motor 33 and can independently send a control signal to each drive motor 33. According to the real-time operating conditions of the engine 100, the control system can adjust the opening of each EGR valve to meet the flow requirements of different EGR channels. This independent control method allows the control system to dynamically adjust the opening of each EGR valve for different operating conditions to achieve optimal EGR rate control. Since each EGR valve is controlled by an independent drive motor 33, the control system can adjust the opening of each EGR valve according to the real-time needs of the engine 100. This precise control improves the response speed and adjustment accuracy of the EGR system 30, ensures that the engine 100 can obtain the best EGR rate under various operating conditions, and optimizes combustion efficiency and emission control.

[0047] It is understandable that the engine 100 includes a supercharging device 20, the outlets of the exhaust manifold branch 12 are all connected to the inlet of the supercharging device 20, and the inlet of the exhaust manifold main road 13 is connected to the outlet of the supercharging device 20. The engine 100 is equipped with a supercharging device 20, and its inlet is respectively connected to the outlet of the exhaust manifold branch 12. The supercharging device 20 compresses the fresh intake air using the kinetic energy of the exhaust gas introduced by the exhaust manifold branch 12, thereby increasing the intake pressure.

[0048] Specifically, the boosting device 20 is provided with a bleed valve 21, which is used to release the pressure when the gas pressure in the boosting device 20 is too high. The bleed valve 21 is installed at the outlet of the boosting device 20 or other appropriate positions. When the gas pressure in the boosting device 20 reaches the set safety threshold, the bleed valve 21 will automatically open to release excess compressed gas to avoid excessive system pressure. The bleed valve 21 is usually driven by a spring-loaded mechanical structure or an electric control system. When the gas pressure exceeds the threshold, the spring is compressed or the electric device receives a signal, and the valve opens to discharge excess gas. The boosting device 20 is provided with a bleed valve 21. When the system pressure is too high, the bleed valve 21 automatically opens to release excess pressure, thereby preventing the compressor from being damaged due to excessive pressure. This design effectively protects the safe operation of the boosting device 20 and the engine 100 and extends the service life of key components.

[0049] In a specific embodiment, there are two exhaust ports, and the two exhaust ports are opened on opposite sides of the cylinder 10. There are two exhaust manifold branches 12, namely a first branch 121 and a second branch 122. There are also two EGR channels, one of which is a first EGR channel connected to the first branch 121 and has a first EGR valve 31, and the other is a second EGR channel connected to the second branch 122 and has a second EGR valve 32. The first EGR valve 31 is directly connected to the drive motor 33, and the second EGR valve 32 is connected to the drive motor 33 through an electromagnetic clutch 34. In this embodiment, through the symmetrical layout of the two exhaust ports and the corresponding exhaust manifold branches 12, the embodiment achieves balanced distribution of exhaust gas during the exhaust process, reduces the flow unevenness of the supercharging device 20, and improves the working efficiency of the supercharging device 20 and the overall power output of the engine 100. Since the first EGR valve 31 is directly connected to the drive motor 33, accurate exhaust gas flow regulation can be achieved, especially under low flow conditions, the control system can ensure emission consistency through fine adjustment. When the demand increases, the introduction of the electromagnetic clutch 34 enables the second EGR valve 32 to synchronously participate in the regulation when needed, thereby ensuring the emission control effect under large flow conditions.

[0050] It is understood that the first branch 121 is connected to the exhaust port on one side of the cylinder 10, and the exhaust gas discharged from this side is directed to the supercharger 20, and part of the exhaust gas is processed through the connected EGR channel. The second branch 122 is connected to the exhaust port on the other side of the cylinder 10, and the exhaust gas discharged from this side is directed to the supercharger 20, and part of the exhaust gas is processed through another EGR channel. The first EGR channel is connected to the first exhaust manifold branch 12 and is equipped with a first EGR valve 31. The first EGR valve 31 is directly connected to the drive motor 33, and the reflux amount of the exhaust gas in the first EGR channel is adjusted by the control of the drive motor 33. The second EGR channel is connected to the second exhaust manifold branch 12, and is equipped with a second EGR valve 32. The second EGR valve 32 is connected to the same drive motor 33 through an electromagnetic clutch 34. When the electromagnetic clutch 34 is closed, the power of the drive motor 33 is simultaneously transmitted to the second EGR valve 32, thereby controlling its opening. Under low load or low speed conditions, the control system sets the electromagnetic clutch 34 to the disconnected state, at which time the drive motor 33 only controls the opening of the first EGR valve 31 to accurately adjust the exhaust gas recirculation through the first EGR channel. The second EGR valve 32 is in the closed position. Under high load or high speed conditions that require a large EGR flow, the control system closes the electromagnetic clutch 34, allowing the drive motor 33 to simultaneously control the opening of the first and second EGR valves 32. This synchronous control ensures that the exhaust gas recirculation of the two EGR channels can meet the higher flow requirements and optimize the emission and combustion performance of the engine 100.

[0051] Specifically, the drive motor 33 and the first EGR valve 31 are connected through gear transmission, the rotating shaft of the drive motor 33 is connected to the valve stem of the first EGR valve 31 through a gear set, and the rotational motion of the drive motor 33 is transmitted through the gear set, thereby adjusting the opening of the first EGR valve 31. The drive motor 33 is connected to the engine 100 control unit, and the ECU sends a control signal to the drive motor 33 according to the real-time working conditions (such as speed and load) of the engine 100. The control signal is usually a voltage or pulse signal, which determines the rotation angle and speed of the drive motor 33, thereby affecting the opening of the first EGR valve 31. When the ECU detects that the EGR flow needs to be increased, the drive motor 33 receives an instruction to increase the opening, the drive motor 33 rotates, and gradually opens the first EGR valve 31 through a mechanical connection mechanism to increase the exhaust gas recirculation amount.

[0052] Specifically, when the EGR demand is greater than the set threshold, the electromagnetic clutch 34 is closed, and the drive motor 33 controls the opening of the first EGR valve 31 and the second EGR valve 32 at the same time. The ECU obtains the operating conditions (such as speed and load) of the engine 100 in real time, and queries the EGR flow mapping table based on these data to calculate the current required EGR flow. If the calculated EGR demand is greater than the set threshold, the ECU determines that the current operating condition requires a larger EGR flow to maintain the combustion efficiency and emission control of the engine 100. When the EGR demand exceeds the set threshold, the control system issues an instruction to close the electromagnetic clutch 34. The closing of the electromagnetic clutch 34 transmits the power of the drive motor 33 to the control mechanism of the second EGR valve 32, so that it is adjusted synchronously with the first EGR valve 31. Through the linkage mechanism of the electromagnetic clutch 34, the rotational movement of the drive motor 33 can simultaneously adjust the opening of the first EGR valve 31 and the second EGR valve 32 to provide a larger exhaust gas recirculation volume. The drive motor 33 receives a signal from the control system and starts to adjust the opening of the first EGR valve 31 and the second EGR valve 32. The rotation of the motor is transmitted to the two EGR valves through a mechanical connection, so that their openings change synchronously. According to the current EGR demand, the ECU accurately calculates the openings of the two EGR valves to ensure that the required EGR flow can reach the set target. This synchronous control can provide sufficient exhaust gas recirculation under high load conditions to reduce combustion temperature and reduce NOx emissions. Through the closing of the electromagnetic clutch 34, the drive motor 33 can control the two EGR valves at the same time, realize accurate control of large-flow exhaust gas recirculation, and ensure that the engine 100 can maintain the optimal EGR rate under high load conditions.

[0053] Specifically, the electromagnetic clutch 34 is located between the drive motor 33 and the second EGR valve 32. It realizes the transmission or cut-off of power through electromagnetic control. The electromagnetic clutch 34 includes an electromagnetic coil, a movable disk, a fixed disk and a transmission shaft. When the electromagnetic clutch 34 is not energized, the movable disk is separated from the fixed disk, and the power of the drive motor 33 is only transmitted to the first EGR valve 31; when the electromagnetic clutch 34 is energized, the electromagnetic coil generates a magnetic field, attracts the movable disk and the fixed disk, so that the power of the drive motor 33 can be transmitted to the second EGR valve 32 through the electromagnetic clutch 34. The second EGR valve 32 is connected to the electromagnetic clutch 34 through a set of transmission mechanisms. Generally, this connection can be achieved through gear transmission, chain transmission or connecting rod mechanism. When the electromagnetic clutch 34 is closed, the power of the drive motor 33 is transmitted to the second EGR valve 32 through the electromagnetic clutch 34 to adjust its opening.

[0054] It can be understood that the control system is an ECU.

[0055] It is understandable that the EGR system 30 also includes an EGR cooler 35, and the outlets of the two EGR channels are both connected to the inlet of the EGR cooler 35, and the outlet of the EGR cooler 35 is connected to the intake manifold 11. The main function of the EGR cooler 35 is to reduce the temperature of the exhaust gas returning to the intake manifold 11. By cooling the exhaust gas through the cooler, its temperature can be significantly reduced, thereby reducing the temperature of the mixed gas entering the cylinder 10. This helps to reduce the nitrogen oxides generated during the combustion process and improve emission performance. By connecting the outlets of the two EGR channels to an EGR cooler 35, the complexity of the engine 100 is reduced.

[0056] Specifically, a detection member 36 is also provided on the pipeline from the EGR cooler 35 to the intake manifold 11, and the detection member 36 includes a temperature sensor and a pressure sensor. The temperature sensor is installed on the pipeline from the EGR cooler 35 to the intake manifold 11, and is used to detect the temperature of the exhaust gas after passing through the cooler in real time. The temperature sensor can transmit the detected temperature data to the ECU as an important basis for adjusting the EGR system 30 and other engine 100 working conditions. The pressure sensor is also installed on the pipeline from the EGR cooler 35 to the intake manifold 11, and is used to monitor the pressure of the exhaust gas. This sensor can detect the pressure change of the cooled exhaust gas in the pipeline and feed the data back to the ECU. The temperature sensor ensures that the temperature of the cooled exhaust gas is within the ideal range to prevent overheated exhaust gas from entering the cylinder 10 and affecting the combustion process. The ECU can adjust the opening of the EGR valve, the working efficiency of the cooler, and other relevant parameters of the engine 100 according to the temperature data to optimize the combustion efficiency and emission control. The pressure sensor monitors the pressure change in the EGR pipeline in real time to ensure that there is no excessively high or low pressure fluctuation in the exhaust gas during the reflow process. The ECU can adjust the opening of the EGR valve based on the pressure data to ensure the stability of the exhaust flow and the normal operation of the system.

[0057] Specifically, the supercharging device 20 is a turbine, and the mechanical energy of the turbine is transmitted to the compressor through a coaxial connection. The compressor is installed in the intake system and is responsible for compressing the air entering the engine 100. When the impeller of the turbine rotates, it drives the impeller of the compressor, which compresses the air and increases the density and pressure of the air. The supercharged air is delivered to the intake manifold 11 and finally enters the cylinder 10. This increase in compressed air allows more oxygen to be used for each combustion, thereby improving the combustion efficiency and the power output of the engine 100.

[0058] It is understandable that the conventional EGR system 30 usually adopts a single-side air intake design, that is, exhaust gas is taken out from one side of the exhaust system and guided back to the intake system through an EGR channel. However, in the single-side air intake EGR system 30, the exhaust gas is only taken out from one exhaust manifold branch 12 and flows back to the intake manifold 11. This design causes the exhaust gas flow to be unbalanced between different exhaust channels, especially when the operating conditions of the engine 100 vary greatly, this imbalance phenomenon is more obvious. Due to the uneven exhaust gas flow, the kinetic energy of the exhaust gas entering the turbine is also uneven. This will cause the turbine impeller to be subjected to uneven driving force, reduce the efficiency of the turbine, and further affect the overall performance of the supercharging system and the fuel economy of the engine 100. In addition, in the single-side air intake design, the turbine often bears a higher heat load, resulting in local overheating. This local overheating not only reduces the durability of the engine 100, but may also cause accelerated aging and damage to the turbine and other components. In this embodiment, the double-sided air intake design allows the exhaust gas to be evenly distributed in the two EGR channels, avoiding the problem of uneven flow caused by single-sided air intake. The balanced exhaust gas flow ensures the uniformity of kinetic energy entering the turbine, improves the working efficiency of the turbine and the overall performance of the engine 100.

[0059] Specifically, the outlet of the turbine is connected to the inlet of the exhaust manifold main path 13, and the exhaust manifold main path 13 is responsible for guiding the exhaust gas from the turbine to the post-processor. The exhaust manifold main path 13 is designed to withstand the flow of high-temperature and high-pressure exhaust gas to ensure that the exhaust gas can flow smoothly to the post-processing device 40. The post-processing device 40 may include an oxidation catalyst (DOC), a selective catalytic reducer (SCR), and a particulate filter (DPF), etc.

[0060] It should be understood that the direction of the arrow in the figure is the direction of gas flow.

[0061] This embodiment also provides a vehicle, comprising the above-mentioned engine 100.

[0062] like Figure 2 As shown, in addition, this embodiment also provides a method for controlling the EGR exhaust gas flow rate, which is implemented according to the above-mentioned engine 100, and includes the following steps:

[0063] Acquiring the operating condition of the engine 100;

[0064] According to the operating conditions, check the EGR flow mapping table (such as Figure 3 As shown) to obtain the EGR demand;

[0065] According to the EGR demand being within a preset range, the exhaust gas flow rates of at least two EGR channels are controlled respectively.

[0066] According to the control method of the EGR exhaust gas flow rate of this embodiment, by looking up the EGR demand amount obtained in the mapping table, the system can accurately control the exhaust gas flow rate of each EGR channel according to the real-time working condition of the engine 100. This precise flow control ensures that each EGR channel can provide a suitable exhaust gas recirculation amount according to actual demand, thereby achieving optimized regulation of the entire EGR system 30.

[0067] Further, the step of controlling the exhaust gas flow of at least two EGR channels respectively according to the EGR demand being within a preset range includes:

[0068] If the EGR demand is less than or equal to a set threshold, one EGR valve is controlled to open (for example, by a drive motor), and the other EGR valves are closed, and the opening value of the opened EGR valve is controlled;

[0069] If the EGR demand is greater than the set threshold, at least two EGR valves are controlled to open (for example, by driving the drive motor to simultaneously close the electromagnetic clutch 34 ), and the opening values ​​of the opened EGR valves are controlled respectively.

[0070] In a specific embodiment, there are two EGR valves, namely a first EGR valve 31 and a second EGR valve 32. The method for controlling the EGR exhaust gas flow rate includes the following steps:

[0071] Acquiring the operating condition of the engine 100;

[0072] According to the operating conditions, the EGR flow mapping table is checked to obtain the EGR demand;

[0073] If the EGR demand is less than or equal to the set threshold, the first EGR valve 31 is controlled to open, the second EGR valve 32 is closed, and the opening value of the first EGR valve 31 is controlled;

[0074] If the EGR demand is greater than the set threshold, at least the first EGR valve 31 and the second EGR valve 32 are controlled to open, and the opening values ​​of the first EGR valve 31 and the second EGR valve 32 are controlled respectively.

[0075] It can be understood that the operating conditions of the engine 100 include rotation speed and torque.

[0076] In a specific embodiment, the threshold value may be set to 30 kg / h.

[0077] Example 1

[0078] When the operating condition of the engine 100 indicates that the EGR demand is less than or equal to 30 kg / h, the EGR system 30 only controls the first EGR valve 31 to open and the second EGR valve 32 to remain closed. This solution is suitable for the operation of the engine 100 under low load or low speed conditions.

[0079] Example 2

[0080] When the EGR demand is greater than the set 30kg / h threshold, the EGR system 30 controls both the first EGR valve 31 and the second EGR valve 32 to open to meet the EGR demand of the engine 100 under high load and high speed conditions. The system controls the first EGR valve 31 and the second EGR valve 32 to open at the same time. According to the calculated EGR demand, the openings of the two EGR valves are adjusted respectively to achieve a larger exhaust gas recirculation volume, ensuring that the EGR system 30 can meet the demand under high load conditions.

[0081] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. An engine, characterized in that: include: A cylinder, wherein the cylinder is provided with an air inlet and at least two exhaust ports, wherein the air inlet is connected to an intake manifold; at least two exhaust manifold branches, the number of the exhaust manifold branches is the same as the number of the exhaust ports, and the inlets of the exhaust manifold branches are connected to the exhaust ports in a one-to-one correspondence; An EGR system, the EGR system comprising at least two EGR channels, the inlets of the EGR channels being in one-to-one communication with the exhaust manifold branches, and the outlets of each of the EGR channels being in communication with the intake manifold; A control system, each of the EGR channels is connected to the control system, and the control system is used to control the exhaust gas flow of at least two of the EGR channels respectively.

2. The engine according to claim 1, characterized in that An EGR valve is disposed in each of the EGR passages, and the EGR valve disposed in at least one of the EGR passages is connected to a driving motor.

3. The engine according to claim 2, characterized in that The control system includes an electromagnetic clutch, one of the EGR valves is connected to the drive motor, and the remaining EGR valves are connected to the drive motor through the electromagnetic clutch.

4. The engine according to claim 1, characterized in that The EGR system further includes an EGR cooler, the outlets of the EGR passages are all connected to the inlet of the EGR cooler, and the outlet of the EGR cooler is connected to the intake manifold.

5. The engine according to claim 1, characterized in that The number of the exhaust ports is two, and the two exhaust ports are opened on opposite sides of the cylinder along the cylinder hole arrangement direction of the cylinder.

6. The engine according to any one of claims 1 to 5, characterized in that: The engine comprises a supercharging device, and outlets of the exhaust manifold branches are all connected to the supercharging device.

7. The engine according to claim 6, characterized in that The boosting device is provided with an air release valve, and the air release valve is used to release the pressure when the gas pressure in the boosting device is too high.

8. A vehicle, characterized in that: Comprising an engine according to any one of claims 1 to 7.

9. A method for controlling EGR exhaust gas flow, characterized in that: The method is used for implementing the engine according to any one of claims 1 to 7, comprising the following steps: Obtaining the operating conditions of the engine; According to the operating conditions, the EGR demand is obtained by looking up a table; According to the EGR demand being within a preset range, the exhaust gas flow rates of at least two of the EGR channels are controlled respectively.

10. The method for controlling the EGR exhaust gas flow rate according to claim 9, characterized in that: The step of controlling the exhaust gas flow of at least two of the EGR channels respectively according to the EGR demand comprises: If the EGR demand is less than or equal to a set threshold, one of the EGR valves is controlled to be opened, and the other EGR valves are closed, and the opening value of the opened EGR valve is controlled; If the EGR demand is greater than a set threshold, at least two of the EGR valves are controlled to open, and the opening values ​​of the opened EGR valves are controlled respectively.

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