Low-pressure cooling EGR system applied to all-in-one motor controller
By optimizing the structure and component design of the low-pressure cooling EGR system, the layout problem of the EGR system in new energy vehicles is solved, the cooling performance and reliability are improved, and the fuel consumption and emission requirements are met.
Patent Information
- Application Number
- CN202511010912.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-22
- Publication Date
- 2025-09-05
AI Technical Summary
Traditional cooled EGR systems are difficult to arrange in new energy vehicles due to compact space, and are prone to carbon deposits and corrosion, affecting cooling performance and reliability.
A low-pressure cooling EGR system is adopted. By arranging the EGR cooler horizontally with a reserved inclination angle, combined with a large-pitch fin structure and a 90-degree vertical airway design, the cooler core and valve connection are optimized to ensure installation space and cooling efficiency.
It achieves stable installation in a small space, prevents carbon deposits and corrosion, improves cooling performance and EGR rate, reduces fuel consumption and NOx emissions, and extends system life.
Smart Images
Figure CN120592772A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of engine exhaust gas recirculation, and in particular relates to a low-pressure cooling EGR system applied to an all-in-one motor controller. Background Art
[0002] Faced with increasingly stringent fuel consumption and emissions regulations worldwide, cooled EGR (exhaust gas recirculation) technology has become a core solution for gasoline engines to achieve energy conservation and emissions reduction. By cooling a portion of the exhaust gas and introducing it into the intake system, this technology not only effectively reduces fuel consumption (especially under part-load conditions), but also reduces NOx emissions by suppressing high-temperature reactions within the cylinder, achieving a synergistic improvement in both economy and environmental performance. However, traditional cooled EGR systems still have significant limitations in practical applications. In pre-catalyst intake scenarios, the exhaust gas contains a high concentration of impurities, which can easily form carbon deposits on the cooler core, leading to airway blockage. Furthermore, if the acidic condensate generated during the exhaust cooling process is not promptly discharged, it can exacerbate core corrosion and affect cooling performance stability.
[0003] At the same time, to meet the demand for lightweight and efficient vehicles, new energy vehicles have generally adopted a core component integration solution. This combines the motor, electronic control, and reducer into a single module. Compared with traditional split-type structures, this significantly reduces volume and weight, and further improves system efficiency by shortening the power transmission path. However, integration also brings new challenges: the installation space between the rear end of the engine and the all-in-one motor is significantly compressed. Traditional EGR systems, due to their loose structure and large size, are difficult to adapt to compact layouts. Moreover, the dense component density increases the difficulty of heat dissipation and space coordination, further limiting the flexibility of EGR system layout. Summary of the Invention
[0004] In order to solve the problems existing in the background technology, the present invention provides a low-pressure cooling EGR system applied to an all-in-one motor controller.
[0005] To achieve the above objectives, the present invention adopts the following technical solutions: a low-pressure cooling EGR system applied to an all-in-one motor controller, comprising an EGR cooler, an EGR valve, a cylinder head, a first mounting bracket, a cooler air outlet chamber, a second mounting bracket, an EGR temperature sensor, a cooler air outlet flange, a water outlet pipe, a third mounting bracket, a cooler air inlet chamber, a cooler air inlet flange, a water inlet pipe, and a cooler core; The EGR cooler is fixedly connected to the cylinder head by mounting bracket 1, mounting bracket 2 and mounting bracket 3. The EGR cooler is arranged horizontally at the rear end of the engine, and has a reserved inclination angle as a whole, and the air intake direction is tilted upward. The cooler air inlet chamber is the air inlet end of the EGR cooler, and is fixedly connected and communicated with the external air intake pipe through the cooler air inlet flange. The cooler air outlet chamber is the air outlet end of the EGR cooler, which is provided with a cooler air outlet flange. The cooler core is arranged inside the EGR cooler, and the cooler air inlet chamber, the cooler core and the cooler air outlet chamber are connected in sequence to form an exhaust gas flow path. The air inlet end of the EGR valve is connected to the cooler air outlet chamber, and the water inlet pipe and the water outlet pipe are both connected to the inside of the EGR cooler.
[0006] The EGR valve is provided with an EGR valve flange and an EGR valve airway port. The EGR valve is sealed and fixedly connected to the cooler outlet flange of the EGR cooler through the EGR valve flange. The EGR valve airway port is the outlet end of the EGR valve, and is arranged perpendicularly at 90 degrees to the EGR valve flange to reduce airway flow resistance.
[0007] The EGR temperature sensor is fixedly mounted on the cooler outlet chamber and is used to detect the temperature of the exhaust gas in the cooler outlet chamber.
[0008] The cooler core adopts a fin structure with a large pitch, and its width and length are adapted to the installation space between the rear end of the engine and the all-in-one motor.
[0009] Compared with the prior art, the present invention has the following beneficial effects: 1. Adapt to the narrow installation space and solve the layout problem: In order to solve the problem that the EGR system is arranged at the rear end of the engine and is close to the all-in-one motor and has a small installation space, the width of the EGR cooler core is compressed to the extreme, the number of core layers is controlled, and a horizontal layout is adopted to ensure that the system can be installed at the rear end of the engine and maintain a reasonable gap with the all-in-one motor to meet the space restriction requirements; the overall structural design is compact, the EGR cooler and the EGR valve are directly fixed, and are stably connected to the cylinder head through the mounting bracket (7, 9, 13), without taking up too much additional space, and adapting to the development trend of the integration of core components of new energy vehicles (such as all-in-one motor controllers).
[0010] 2. Improve cooling, anti-carbon deposition and anti-corrosion capabilities: The EGR cooler is optimized in design while ensuring cooling performance. Combined with the coolant circulation (entering through the water inlet pipe and discharged through the water outlet pipe), it can effectively cool the exhaust gas and meet the engine's cooling needs for EGR gas. When the EGR cooler is arranged horizontally, an inclination angle is reserved to make the air flow in the intake path upward, ensuring that the condensed water in the exhaust gas flows back to the cooler, avoiding the accumulation of acidic condensate in the core and reducing the risk of corrosion. It is especially suitable for scenarios with complex exhaust gas composition during pre-catalyst gas extraction. The cooler core adopts a fin structure with a large pitch and a shortened length to reduce the residence time and flow resistance of the exhaust gas in the core, reduce the probability of impurity deposition and coking and carbon deposition in the pre-catalyst exhaust gas, avoid system blockage, and improve the anti-carbon deposition capability.
[0011] 3. Ensure EGR rate and optimize engine performance and emissions: The EGR valve airway port and the EGR valve flange are designed to be perpendicular at 90 degrees, which reduces airway flow resistance, ensures sufficient exhaust gas flow, and guarantees the EGR rate required by the engine, thereby achieving the effect of reducing fuel consumption and NOx emissions, meeting strict fuel consumption and emission requirements; the use of pre-catalyst air cooling EGR technology, combined with the above-mentioned cooling and anti-clogging design, not only plays the role of optimizing the technology on engine emissions and fuel consumption, but also avoids the system problems that are easily caused by traditional pre-catalyst air extraction.
[0012] 4. Improve system reliability and service life: By controlling the number of cooler core layers and cooling efficiency, optimizing the core structure (large pitch fins, compressed dimensions), and designing a reasonable inclination angle, damage to the system caused by carbon deposits and corrosion is reduced, the probability of failure is reduced, and the system service life is extended. The EGR temperature sensor is fixed in the exhaust chamber and can detect the exhaust gas temperature in real time, providing a basis for adjusting the cooling efficiency, ensuring stable operation of the system under different operating conditions, and improving reliability.
[0013] In summary, the low-pressure cooling EGR system used in the all-in-one motor controller effectively solves the layout problem of the close distance between the rear end of the engine and the all-in-one motor by optimizing the structural layout (such as compact size and reserved inclination angle) and improving the design of core components (such as large-pitch fins and vertical airway valves). At the same time, it takes into account cooling performance, anti-carbon deposition and anti-corrosion capabilities, and ensures the EGR rate. It not only adapts to the integration requirements of new energy vehicles, but also optimizes engine fuel consumption and emissions, significantly improving the reliability and practicality of the system. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 It is a schematic diagram of the arrangement of the cooling EGR system of the present invention; Figure 2 It is a schematic diagram of the connection relationship between the EGR valve and the EGR cooler of the present invention. DETAILED DESCRIPTION
[0015] The technical solutions of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.
[0016] This embodiment describes a low-pressure cooled EGR system for an all-in-one motor controller, including an EGR cooler 1, an EGR valve 3, a cylinder head 6, a mounting bracket 1 7, a cooler outlet chamber 8, a mounting bracket 2 9, a cooler outlet flange 11, a water outlet pipe 12, a mounting bracket 3 13, a cooler inlet chamber 14, a cooler inlet flange 15, a water inlet pipe 16, and a cooler core 17. The EGR cooler 1 is fixedly connected to the cylinder head 6 through the mounting bracket 1 7, the mounting bracket 2 9 and the mounting bracket 3 13. The EGR cooler 1 is arranged horizontally at the rear end of the engine, and an overall inclination angle is reserved. The air intake direction is tilted upward. The inclination angle makes the air flow in the intake path flow upward, ensuring that the condensed water in the exhaust gas flows back to the cooler, and a preset installation gap is set between the EGR cooler 1 and the all-in-one motor 2. The cooler air inlet chamber 14 is the air intake end of the EGR cooler 1, and is fixedly connected and communicated with the external air intake pipe (the air intake pipe before the three-way catalytic converter) through the cooler air inlet flange 15. The cooler air outlet chamber 8 is the air outlet end of the EGR cooler 1. A cooler outlet flange 11 is provided, and a cooler core 17 is arranged inside the EGR cooler 1. Its width is compressed to a minimum while ensuring cooling performance and anti-carbon deposition capability to adapt to the installation space between the rear end of the engine and the all-in-one motor 2, and the cooler air inlet chamber 14, the cooler core 17 and the cooler air outlet chamber 8 are connected in sequence to form an exhaust gas flow path. The air inlet end of the EGR valve 3 is connected to the cooler air outlet chamber 8, and the water inlet pipe 16 and the water outlet pipe 12 are both connected to the inside of the EGR cooler 1. The coolant enters the EGR cooler 1 through the water inlet pipe 16, and is discharged from the water outlet pipe 12 after heat exchange with the exhaust gas in the cooler core 17.
[0017] The EGR valve 3 is provided with an EGR valve flange 5 and an EGR valve airway port 4. The EGR valve 3 is sealed and fixedly connected to the cooler outlet flange 11 of the EGR cooler 1 through the EGR valve flange 5. The EGR valve airway port 4 is the outlet end of the EGR valve 3. It is arranged perpendicularly at 90 degrees to the EGR valve flange 5 to reduce the airway flow resistance. The reduced flow resistance can ensure the EGR rate required by the engine.
[0018] The EGR temperature sensor 10 is fixedly mounted on the cooler outlet chamber 8 and is used to detect the temperature of the exhaust gas in the cooler outlet chamber 8. The detection result is used to feedback and adjust the cooling efficiency of the cooler to match the engine operation requirements.
[0019] The cooler core 17 adopts a fin structure with a large pitch, and its width and length are adapted to the installation space between the rear end of the engine and the multi-in-one motor 2. The fin structure with a large pitch can reduce the residence time of the exhaust gas in the core, reduce the risk of impurity deposition in the exhaust gas taken before catalysis, and avoid system blockage caused by coking and carbon deposition.
[0020] The working principle of the low-pressure cooling EGR system applied to the all-in-one motor controller is as follows: the exhaust gas is drawn out from the air intake point in front of the engine's three-way catalytic converter, transported to the air intake flange 15 of the EGR cooler through an external air intake pipe, and enters the EGR cooler 1 through the cooler air intake chamber 14. This system is a low-pressure cooling EGR system, which means that the exhaust gas enters the EGR cooler under low pressure (lower than the intake manifold pressure), which is adapted to the low-pressure working conditions of the extended-range engine; the coolant enters the EGR cooler 1 through the water inlet pipe 16, and exchanges heat with the exhaust gas in the cooler core 17. When the high-temperature exhaust gas flows in the core, the heat is absorbed by the coolant to achieve cooling. The coolant after heat exchange is discharged through the water outlet pipe 12 to complete the cooling cycle. At the same time, the cooler core 17 adopts a fin structure with a large pitch and pressure The shortened length and large pitch fins reduce the exhaust gas flow resistance. The shortened length shortens the exhaust gas residence time and reduces the probability of impurity deposition. When the EGR cooler 1 is arranged horizontally, an upward inclination angle of the air intake direction is reserved, so that the liquid formed by the condensation of water vapor in the exhaust gas can flow back to the bottom along the inclined core, avoiding the residual acidic condensate to reduce corrosion; the cooled exhaust gas enters the EGR valve 3 from the cooler outlet chamber 8. The EGR valve 3 is sealed and connected to the cooler outlet flange 11 through the EGR valve flange 5 to ensure no leakage. The airway port 4 and the EGR valve flange 5 are designed to be 90 degrees vertical to reduce the airway flow resistance to ensure sufficient exhaust gas flow and achieve the expected EGR rate; the EGR temperature sensor 10 fixed on the cooler outlet chamber 8 detects the cooled exhaust gas temperature in real time and adjusts the EGR rate (EGR) for the engine control system The EGR cooler 1 is secured to the cylinder head 6 via mounting brackets 1 7 , 2 9 , and 3 13 . The EGR valve 3 is directly secured to the cooler. By compressing the cooler core 17 and controlling the mounting clearance, the cooler ensures stable operation without component interference within the narrow space between the rear end of the engine and the all-in-one motor 2 .
[0021] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.
Claims
1. A low-pressure cooled EGR system for an all-in-one motor controller, characterized by: It includes an EGR cooler (1), an EGR valve (3), a cylinder head (6), a mounting bracket 1 (7), a cooler air outlet chamber (8), a mounting bracket 2 (9), a cooler air outlet flange (11), a water outlet pipe (12), a mounting bracket 3 (13), a cooler air inlet chamber (14), a cooler air inlet flange (15), a water inlet pipe (16) and a cooler core (17); The EGR cooler (1) is fixedly connected to the cylinder head (6) through mounting bracket 1 (7), mounting bracket 2 (9) and mounting bracket 3 (13). The EGR cooler (1) is arranged transversely at the rear end of the engine and has a reserved inclination angle as a whole, with the air intake direction tilted upward. The cooler air intake chamber (14) is the air intake end of the EGR cooler (1) and is fixedly connected and communicated with the external air intake pipe through the cooler air intake flange (15). The cooler air outlet chamber (8) is the air outlet end of the EGR cooler (1) and is provided with a cooler air outlet flange (11). The cooler core (17) is arranged inside the EGR cooler (1), and the cooler air intake chamber (14), the cooler core (17) and the cooler air outlet chamber (8) are connected in sequence to form an exhaust gas flow path. The air intake end of the EGR valve (3) is communicated with the cooler air outlet chamber (8), and the water inlet pipe (16) and the water outlet pipe (12) are both communicated with the inside of the EGR cooler (1).
2. The low-pressure cooling EGR system for an all-in-one motor controller according to claim 1, characterized in that: The EGR valve (3) is provided with an EGR valve flange (5) and an EGR valve airway port (4). The EGR valve (3) is sealed and fixedly connected to a cooler outlet flange (11) of the EGR cooler (1) via the EGR valve flange (5). The EGR valve airway port (4) is the outlet end of the EGR valve (3) and is arranged vertically at 90 degrees to the EGR valve flange (5) to reduce airway flow resistance.
3. The low-pressure cooling EGR system applied to the all-in-one motor controller according to claim 1, characterized in that: The low-pressure cooling EGR system applied to the all-in-one motor controller further includes an EGR temperature sensor (10), wherein the EGR temperature sensor (10) is fixedly mounted on the cooler outlet chamber (8) and is used to detect the temperature of the exhaust gas in the cooler outlet chamber (8).
4. The low-pressure cooling EGR system for an all-in-one motor controller according to claim 1, characterized in that: The cooler core (17) adopts a fin structure with a large pitch, and its width and length are adapted to the installation space between the rear end of the engine and the all-in-one motor (2).