Supercharged gasoline engine with high-pressure EGR and vehicle

Abstract

The utility model discloses a supercharged gasoline engine with a high-pressure EGR (exhaust gas recirculation) function and a vehicle, and belongs to the technical field of automobiles. The supercharged gasoline engine comprises a plurality of air cylinders, a piston is arranged in each air cylinder, the pistons are connected with the crankshaft and drive the crankshaft to rotate, and the combustion chamber is formed by the air cylinders and air cylinder heads. The engine is provided with a high-pressure EGR system, an EGR gas inlet pipe is connected with an exhaust manifold, part of waste gas is introduced into the high-pressure EGR system to be cooled and then fed into a gas inlet manifold through an EGR gas outlet pipe, the cooled waste gas is mixed with fresh air and then enters a combustion chamber, and the combustion process is optimized. The high-pressure EGR system further comprises an EGR differential pressure sensor and a temperature sensor, and the sensors feed detection data back to the ECU and are used for adjusting the opening degree of the EGR valve. According to the system, the fuel economy is improved, NOx emission is reduced, and the combustion stability of the engine is improved. The supercharged gasoline engine can effectively balance engine performance and emission requirements, and is suitable for various vehicles.

Description

Technical Field

[0001] The utility model relates to the technical field of automobiles, and more specifically, to a supercharged gasoline engine with high-pressure EGR and a vehicle. Background Technique

[0002] In modern automobile engine technology, with the increasingly strict emission regulations, reducing nitrogen oxide (NOx) emissions and improving fuel economy have become one of the main challenges for major automobile manufacturers. To address these challenges, supercharged gasoline engines have gradually become the mainstream. However, traditional supercharged gasoline engines usually match a low-pressure EGR system or do not have an EGR system at all. These two solutions each have their limitations.

[0003] For a supercharged gasoline engine with a low-pressure EGR system, although it can reduce NOx emissions to a certain extent, the complexity of its system increases the manufacturing cost of the engine. For example, a low-pressure EGR system usually requires additional components such as an air-water intercooler and an electric water pump. This not only raises the design and manufacturing costs of the entire engine but also introduces the problem of condensate. Condensate may accumulate in the intake system, especially under low-temperature conditions, and is more likely to affect combustion stability and even cause engine misfires. This phenomenon increases the control difficulty of the ECU, leading to a further increase in system complexity.

[0004] On the other hand, a supercharged gasoline engine without an EGR system has poor fuel economy. At the same time, due to the lack of exhaust gas recirculation, the original NOx emissions are relatively high. To meet the emission standards, such engines usually need to increase the precious metal content in the after-treatment system, such as platinum, palladium, rhodium, etc. in the three-way catalytic converter. This not only significantly increases the cost of the after-treatment system but also limits the performance optimization of the engine to a certain extent. Therefore, how to control costs and improve the combustion stability of the engine while ensuring emission standards has become an urgent problem to be solved in the current supercharged gasoline engine technology. Content of the Utility Model

[0005] The utility model provides a supercharged gasoline engine with high-pressure EGR and a vehicle to overcome the disadvantages of the existing supercharged gasoline engine with a low-pressure EGR system, such as complex system, high cost, poor combustion stability caused by condensate problems, and poor fuel consumption, high NOx emissions, and increased after-treatment costs without an EGR system.

[0006] To solve the above technical problems, the technical solution of the utility model is as follows:

[0007] A supercharged gasoline engine with high-pressure EGR, wherein several cylinders are provided in the cylinder block of the supercharged gasoline engine, a piston is arranged in each cylinder, each piston is connected with a crankshaft, and each piston is configured to move up and down in the cylinder to execute the work cycle of the supercharged gasoline engine, thereby driving the crankshaft to rotate;

[0008] The top of the cylinder is covered with a cylinder head, and the cylinder head is used to form a combustion chamber together with the cylinder; an air inlet and an exhaust port are arranged on the cylinder head; the air inlet is equipped with an intake manifold for introducing gas into the combustion chamber; the exhaust port is equipped with an exhaust manifold for guiding the exhaust gas generated after combustion out of the combustion chamber;

[0009] A high-pressure EGR system is installed on the cylinder body of the supercharged gasoline engine, and the high-pressure EGR system includes an EGR intake pipe, an EGR cooler, an EGR valve, and an EGR outlet pipe, wherein:

[0010] The EGR intake pipe is connected to the exhaust manifold and is used to introduce part of the exhaust gas in the exhaust manifold into the high-pressure EGR system;

[0011] The EGR cooler is connected to the EGR intake pipe and is used to cool the exhaust gas entering from the EGR intake pipe;

[0012] The EGR valve is connected to the EGR cooler through a pipeline and is used to control the flow rate of the exhaust gas;

[0013] The EGR outlet pipe is connected to the intake manifold and is used for delivering the cooled and regulated exhaust gas to the intake manifold.

[0014] Further, the high-pressure EGR system further comprises an EGR pressure difference sensor, which is installed between the EGR intake pipe and the EGR outlet pipe and is used to detect the pressure difference in the high-pressure EGR system;

[0015] The EGR pressure difference sensor is connected to an ECU control unit, and the EGR pressure difference sensor is used to convert the detected pressure difference information into an electrical signal and send it to the ECU control unit;

[0016] The ECU control unit is connected to the EGR valve, and is used to calculate the opening of the EGR valve based on the pressure difference signal transmitted by the EGR pressure difference sensor and send a control signal to the EGR valve to adjust the opening and closing degree of the EGR valve.

[0017] Furthermore, an EGR temperature sensor is provided in the high-pressure EGR system. The EGR temperature sensor is installed at the outlet of the EGR cooler and is used to monitor the temperature of the cooled exhaust gas and feed back the temperature data to the ECU control unit to optimize the opening adjustment of the EGR valve.

[0018] Furthermore, a spark plug is threadedly mounted on the cylinder, and an electrode end of the spark plug extends into the combustion chamber;

[0019] An ignition coil is installed above the spark plug. The ignition coil is used to apply a high-voltage current to the spark plug to generate an electric spark between the electrodes of the spark plug.

[0020] Furthermore, a manifold injection system is also installed on the cylinder block of the supercharged gasoline engine. The manifold injection system includes a fuel pump, an oil rail, and fuel injectors, where:

[0021] The fuel pump is connected to the oil rail and is used to supply high-pressure fuel;

[0022] A number of fuel injectors are installed on the oil rail, and the oil rail is used to distribute high-pressure fuel to each fuel injector;

[0023] The fuel injector is connected to the intake manifold and is used to inject fuel into the air entering the combustion chamber to form a combustible mixture.

[0024] Furthermore, a supercharger is installed between the exhaust manifold and the high-pressure EGR system. The supercharger is used to increase the pressure in front of the turbine, so that the pressure in front of the turbine is greater than the pressure in the intake manifold.

[0025] Furthermore, a three-way catalytic converter and a particulate trap are sequentially connected to the exhaust manifold. The particulate trap is connected to an exhaust gas pipe, and the exhaust gas pipe is used to discharge the exhaust gas treated by the three-way catalytic converter and the particulate trap.

[0026] Furthermore, the EGR valve is an electronically controlled valve with adjustable opening.

[0027] Furthermore, the EGR outlet pipe is a metal bellows.

[0028] A vehicle, which includes the supercharged gasoline engine with high-pressure EGR described above.

[0029] Compared with the prior art, the beneficial effects of the technical solution of the present utility model are:

[0030] The present utility model provides a supercharged gasoline engine with high-pressure EGR and a vehicle. By adopting a high-pressure EGR system, while reducing NOx emissions, the combustion stability and fuel economy are improved. By precisely controlling the opening of the EGR valve, the combustion process is further optimized and the fuel consumption is reduced. The combination of the spark plug ignition system and the manifold injection system ensures the full combustion of fuel and power output. At the same time, the application of the supercharger significantly increases the intake pressure and engine performance, and the after-treatment system ensures the effective control of emissions. Overall, the supercharged gasoline engine of the present invention has made remarkable progress in balancing emissions and performance and is applicable to various vehicles. Description of the Drawings

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0032] Figure 1 It is a schematic diagram showing the connection between the high-pressure EGR system and the intake manifold in a supercharged gasoline engine with high-pressure EGR provided in an embodiment of the present application;

[0033] Figure 2 It is the front view of a supercharged gasoline engine with high-pressure EGR provided in an embodiment of the present application;

[0034] Figure 3 It is the top view of a supercharged gasoline engine with high-pressure EGR provided in an embodiment of the present application;

[0035] Figure 4 It is the rear view of a supercharged gasoline engine with high-pressure EGR provided in an embodiment of the present application;

[0036] Figure 5 It is the bottom view of a supercharged gasoline engine with high-pressure EGR provided in an embodiment of the present application;

[0037] Marking description in the figure: 1. EGR intake pipe; 2. EGR cooler; 3. EGR valve; 4. EGR outlet pipe; 5. EGR differential pressure sensor; 6. Ignition coil; 7. Fuel rail; 8. Supercharger; 9. Intake manifold. Detailed implementation manners

[0038] To better understand the purpose, structure and function of the present invention, the following will further describe the technical solutions of the present invention in detail with reference to the drawings and specific preferred embodiments.

[0039] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by terms such as "left side", "right side", "upper part", "lower part", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. "First", "second", etc. do not represent the importance of the components, so they cannot be understood as limitations on the present invention. The specific dimensions adopted in the embodiments are only for illustrating the technical solutions by way of example, and do not limit the protection scope of the present invention. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0040] Unless otherwise clearly specified and limited, the terms "install", "set", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0041] Embodiment 1:

[0042] like Figures 1-5 As shown, the utility model provides a technical solution:

[0043] A supercharged gasoline engine with high-pressure EGR, wherein a plurality of cylinders are arranged in a cylinder body of the supercharged gasoline engine, each of the cylinders is provided with a piston, each of the pistons is connected to a crankshaft, and each of the pistons is configured to move up and down in the cylinder to perform a work cycle of the supercharged gasoline engine, thereby driving the crankshaft to rotate;

[0044] The top of the cylinder is covered with a cylinder head, which is used to form a combustion chamber together with the cylinder; an air inlet and an exhaust port are arranged on the cylinder head; the air inlet is equipped with an intake manifold 9 for introducing gas into the combustion chamber; the exhaust port is equipped with an exhaust manifold for guiding the exhaust gas generated after combustion out of the combustion chamber;

[0045] A high-pressure EGR system is installed on the cylinder body of the supercharged gasoline engine, and the high-pressure EGR system includes an EGR intake pipe 1, an EGR cooler 2, an EGR valve 3, and an EGR outlet pipe 4, wherein:

[0046] The EGR intake pipe 1 is connected to the exhaust manifold and is used to introduce part of the exhaust gas in the exhaust manifold into the high-pressure EGR system;

[0047] The EGR cooler 2 is connected to the EGR intake pipe 1 and is used to cool the exhaust gas entering from the EGR intake pipe 1;

[0048] The EGR valve 3 is connected to the EGR cooler 2 through a pipeline to control the flow rate of the exhaust gas;

[0049] The EGR outlet pipe 4 is connected to the intake manifold 9 and is used to deliver the cooled and regulated exhaust gas to the intake manifold 9 so that the exhaust gas can be mixed with fresh air and then enter the combustion chamber to optimize the combustion process.

[0050] The supercharged gasoline engine with high-pressure EGR of this embodiment:

[0051] Compared with low-pressure EGR: There is no need for an air-to-water intercooler, an electric water pump, etc., which reduces the engine cost. At the same time, the condensate water of high-pressure EGR is easy to control, and the ECU control is relatively simple;

[0052] Compared with non-EGR: The engine with EGR has better fuel consumption. At the same time, due to the reduction of the original NOx emissions, the precious metal content in the aftertreatment can be reduced, thereby reducing the aftertreatment cost.

[0053] Example 2:

[0054] On the basis of Example 1, referring to Figures 1-5 , the high-pressure EGR system further includes an EGR differential pressure sensor 5, and the EGR differential pressure sensor 5 is installed between the EGR intake pipe 1 and the EGR outlet pipe 4 for detecting the pressure difference in the high-pressure EGR system;

[0055] The EGR differential pressure sensor 5 is connected to an ECU control unit, and the EGR differential pressure sensor 5 is used to convert the detected pressure difference information into an electrical signal and send it to the ECU control unit;

[0056] The ECU control unit is connected to the EGR valve 3, and the ECU control unit is used to calculate the opening degree of the EGR valve 3 based on the pressure difference signal transmitted by the EGR differential pressure sensor 5 and send a control signal to the EGR valve 3 to adjust the opening and closing degree of the EGR valve 3.

[0057] Furthermore, an EGR temperature sensor is provided in the high-pressure EGR system. The EGR temperature sensor is installed at the outlet of the EGR cooler 2 for monitoring the temperature of the cooled exhaust gas and feeding back the temperature data to the ECU control unit to optimize the opening degree adjustment of the EGR valve 3.

[0058] Furthermore, a spark plug is threadedly installed on the cylinder, and the electrode end of the spark plug extends into the combustion chamber;

[0059] An ignition coil 6 is installed above the spark plug, and the ignition coil 6 is used to apply a high-voltage current to the spark plug to generate an electric spark between the electrodes of the spark plug;

[0060] Among them, the ignition coil 6 improves the ignition energy, and the ignition energy can reach 110 mJ, thereby enhancing the combustion stability.

[0061] Furthermore, a manifold injection system is also installed on the cylinder block of the supercharged gasoline engine. The manifold injection system includes a fuel pump, an oil rail 7 and an injector, where:

[0062] The fuel pump is connected to the oil rail 7 for supplying high-pressure fuel;

[0063] A number of fuel injectors are installed on the fuel rail 7, and the fuel rail 7 is used to distribute high-pressure fuel to each fuel injector;

[0064] The assembly of the fuel rail 7 and the fuel injector is installed at the cylinder head air passage;

[0065] The fuel injector is connected to the intake manifold 9 and is used to inject fuel into the air entering the combustion chamber to form a uniform combustible mixture.

[0066] Furthermore, a supercharger 8 is installed between the exhaust manifold and the high-pressure EGR system. The supercharger 8 is used to increase the pressure in front of the turbine, so that the pressure in front of the turbine is greater than the pressure of the intake manifold 9;

[0067] Specifically, the supercharger 8 needs to meet the requirement that in the area where the engine needs to add EGR, the pressure in front of the turbine should be greater than the pressure of the intake manifold, and the pressure difference between the pressure in front of the turbine and the pressure of the intake manifold should be greater than the flow resistance of the EGR system, so that enough exhaust gas can enter the intake manifold 9.

[0068] Furthermore, a three-way catalytic converter and a particulate trap are sequentially connected to the exhaust manifold. The particulate trap is connected to an exhaust gas pipe, and the exhaust gas pipe is used to discharge the exhaust gas treated by the three-way catalytic converter and the particulate trap; that is, the post-treatment adopts the TWC+GPF scheme, which effectively reduces the harmful substance emissions in the exhaust gas and meets the National VI B emission standards.

[0069] Furthermore, the intake manifold 9 borrows the basic naturally aspirated intake manifold, which does not affect the engine performance and saves the development cost.

[0070] Furthermore, the engine adopts the Miller cycle and high compression ratio technology;

[0071] Among them, the Miller cycle is a special internal combustion engine working cycle. Compared with the traditional Otto cycle, it reduces the actual compressed mixture volume in the cylinder during the compression stroke by closing the intake valve early or delaying the closing of the valve, thereby reducing the compression ratio of the engine during the compression stroke; this design can significantly reduce the temperature and pressure in the cylinder, thereby reducing the possibility of knocking and improving the thermal efficiency of the engine; at the same time, the Miller cycle can be used in conjunction with a supercharger to introduce more fresh air during the intake stroke to make up for the insufficient charge caused by closing the intake valve early;

[0072] Among them, the high compression ratio technology refers to increasing the geometric compression ratio of the engine in engine design, that is, the ratio of the maximum volume to the minimum volume in the cylinder at the end of the compression stroke; a higher compression ratio can improve the thermal efficiency of the engine because it can make the fuel burn at a higher pressure, thus generating more power; however, a high compression ratio usually increases the risk of knocking. Therefore, when combined with the Miller cycle, it can effectively reduce the knocking risk while maintaining high thermal efficiency.

[0073] In the present utility model, the Miller cycle and the high compression ratio technology are adopted to further improve the fuel economy and emission performance of the supercharged gasoline engine. By reducing the actual compression ratio in the cylinder through the Miller cycle, the possibility of knocking is reduced, so that the thermal efficiency can be improved while maintaining a high compression ratio. This combination enables the engine to achieve higher combustion efficiency under different operating conditions, reduce fuel consumption, and significantly reduce the emissions of harmful substances such as NOx while increasing the power output.

[0074] Combined with the high-pressure EGR system and the supercharging technology, this design enables the engine to maintain efficient and low-emission operation under a wider range of operating conditions, meeting the dual requirements of modern vehicles for performance and environmental protection.

[0075] Furthermore, the EGR valve 3 is an electronically controlled valve with adjustable opening.

[0076] Furthermore, the EGR outlet pipe 4 is a metal bellows.

[0077] On the basis of Embodiment 1, by adding an EGR differential pressure sensor and a temperature sensor, the precise control ability of the high-pressure EGR system is improved, further increasing the combustion efficiency and reducing fuel consumption. The design of the spark plug and the ignition coil enhances the combustion stability, and the manifold injection system improves the power output of the engine through more uniform fuel injection. The application of the supercharger ensures sufficient EGR flow and optimizes the emission control.

[0078] Embodiment 3:

[0079] The present utility model provides a technical solution: a vehicle, which includes the aforementioned supercharged gasoline engine with high-pressure EGR. Through the technical solution of the supercharged gasoline engine with high-pressure EGR, the vehicle can achieve higher fuel economy and power performance while meeting strict emission standards, and is applicable to various passenger cars and commercial vehicles.

[0080] Obviously, the above embodiments of the present utility model are merely examples for clearly illustrating the present utility model, rather than limitations on the implementation manners of the present utility model. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation manners here. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the claims of the present utility model.

Claims

1. A supercharged gasoline engine with high pressure EGR, characterized in that: The cylinder body of the supercharged gasoline engine is provided with a plurality of cylinders, each of the cylinders is provided with a piston, each of the pistons is connected to a crankshaft, and each of the pistons is configured to move up and down in the cylinder to perform the power cycle of the supercharged gasoline engine, thereby driving the crankshaft to rotate; The top of the cylinder is covered with a cylinder head, and the cylinder head is used to form a combustion chamber together with the cylinder; the cylinder head is provided with an air inlet and an exhaust port; the air inlet is provided with an intake manifold (9) for introducing gas into the combustion chamber; The exhaust port is equipped with an exhaust manifold for guiding the exhaust gas generated after combustion out of the combustion chamber; A high-pressure EGR system is installed on the cylinder body of the supercharged gasoline engine. The high-pressure EGR system comprises an EGR intake pipe (1), an EGR cooler (2), an EGR valve (3), and an EGR outlet pipe (4), wherein: The EGR intake pipe (1) is connected to the exhaust manifold and is used to introduce part of the exhaust gas in the exhaust manifold into the high-pressure EGR system; The EGR cooler (2) is connected to the EGR intake pipe (1) and is used to cool the exhaust gas entering from the EGR intake pipe (1); The EGR valve (3) is connected to the EGR cooler (2) via a pipeline and is used to control the flow rate of the exhaust gas; The EGR outlet pipe (4) is connected to the intake manifold (9) and is used to transport the cooled and regulated exhaust gas to the intake manifold (9).

2. The supercharged gasoline engine with high pressure EGR according to claim 1, characterized in that: The high-pressure EGR system further comprises an EGR pressure difference sensor (5), which is installed between the EGR intake pipe (1) and the EGR outlet pipe (4) and is used to detect the pressure difference in the high-pressure EGR system; The EGR pressure difference sensor (5) is connected to an ECU control unit, and the EGR pressure difference sensor (5) is used to convert the detected pressure difference information into an electrical signal and send it to the ECU control unit; The ECU control unit is connected to the EGR valve (3), and the ECU control unit is used to calculate the opening degree of the EGR valve (3) based on the pressure difference signal transmitted by the EGR pressure difference sensor (5) and send a control signal to the EGR valve (3) to adjust the opening and closing degree of the EGR valve (3).

3. The supercharged gasoline engine with high pressure EGR according to claim 2, characterized in that: The high-pressure EGR system is provided with an EGR temperature sensor, which is installed at the outlet of the EGR cooler (2) and is used to monitor the temperature of the cooled exhaust gas and feed back the temperature data to the ECU control unit to optimize the opening adjustment of the EGR valve (3).

4. The supercharged gasoline engine with high pressure EGR according to claim 1, characterized in that: A spark plug is threadedly mounted on the cylinder, and the electrode end of the spark plug extends into the combustion chamber; An ignition coil (6) is installed above the spark plug, and the ignition coil (6) is used to apply a high voltage current to the spark plug to generate an electric spark between electrodes of the spark plug.

5. The supercharged gasoline engine with high pressure EGR according to claim 1, characterized in that: A manifold injection system is also installed on the cylinder body of the supercharged gasoline engine, and the manifold injection system includes a fuel pump, a fuel rail (7) and a fuel injector, wherein: The fuel pump is connected to the fuel rail (7) and is used to supply high-pressure fuel; A plurality of fuel injectors are installed on the fuel rail (7), and the fuel rail (7) is used to distribute high-pressure fuel to each fuel injector; The fuel injector is connected to the intake manifold (9) and is used for injecting fuel into the air entering the combustion chamber to form a combustible mixed gas.

6. The supercharged gasoline engine with high pressure EGR according to claim 1, characterized in that: A supercharger (8) is installed between the exhaust manifold and the high-pressure EGR system, and the supercharger (8) is used to increase the pre-turbine pressure so that the pre-turbine pressure is greater than the pressure of the intake manifold (9).

7. The supercharged gasoline engine with high pressure EGR according to claim 1, characterized in that: The exhaust manifold is connected with a three-way catalytic converter and a particulate trap in sequence, the particulate trap is connected with an exhaust pipe, and the exhaust pipe is used to discharge the exhaust gas processed by the three-way catalytic converter and the particulate trap.

8. The supercharged gasoline engine with high pressure EGR according to claim 1, characterized in that: The EGR valve (3) is an electrically controlled valve with adjustable opening.

9. The supercharged gasoline engine with high pressure EGR according to claim 1, characterized in that: The EGR outlet pipe (4) is a metal bellows.

10. A vehicle, characterized in that: The vehicle comprises a supercharged gasoline engine with high pressure EGR as claimed in any one of claims 1 to 9.

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