Engine intercooler bypass and EGR cooler bypass control device

Abstract

The present invention provides a control device for engine intercooler bypass and EGR cooler bypass, belonging to the field of engine technology. The control device includes: a multi-way butterfly valve provided with at least three airflow channels, the input end of which is connected to a supercharger; an EGR cooler disposed on an EGR cooling branch, one end of the EGR cooling branch being connected to an EGR circuit and the other end being connected to an intake manifold; an EGR bypass branch, one end of which is connected to the EGR circuit via a first airflow channel of the multi-way butterfly valve and the other end being connected to the EGR cooling branch and located between the EGR cooler and the intake manifold; an intercooler bypass branch, one end of which is connected to the intake manifold and the other end being connected to a second airflow channel of the multi-way butterfly valve; and an intercooler, one end of which is connected to the intake manifold and the other end being connected to a third airflow channel of the multi-way butterfly valve. By adding the multi-way butterfly valve, the present invention achieves the purpose of simultaneously adjusting the cooling strategies of both the EGR system and the intercooler system.

Description

Technical Field

[0001] The present invention relates to the technical field of engines, and in particular to a control device for engine intercooler bypass and EGR cooler bypass. Background Art

[0002] The primary function of an EGR (Exhaust Gas Recirculation) system cooler is to reduce the temperature of exhaust gas flowing back from the exhaust system to the intake system. This is because during engine operation, some of the burned exhaust gas is reintroduced into the intake system, mixed with fresh air, and then re-entered the cylinder for combustion. However, this exhaust gas is typically at a high temperature. If not cooled, it can cause excessive heat loads on engine components such as the intake system, cylinder walls, and pistons, affecting engine performance and life.

[0003] When an engine uses turbocharging or supercharging technology, the supercharger significantly increases intake air pressure, but this also increases intake air temperature. High-temperature air reduces air density, which in turn affects the engine's charging efficiency. An intercooler cools the supercharged air, reducing its temperature and increasing intake air density, allowing the engine to inhale more dense air.

[0004] However, during engine operation, due to the complexity of the operating conditions, it is sometimes necessary to adjust the cooling effect of the intake system to adapt to different needs. For example, when the engine is running in a cold environment with low load, especially in the initial stage after a cold start, due to the low EGR rate and relatively low exhaust temperature under natural conditions, if the same cooling strategy as the high-load condition is adopted at this time, that is, all the exhaust gas in the EGR branch is allowed to flow through the EGR cooler for cooling, it may cause the exhaust gas to have an abnormally low temperature when it flows out of the EGR module. Similarly, due to the low external ambient temperature, if the pressurized air is still cooled through the intercooler at this time, it may cause the intake air temperature to be too low, which will have an adverse effect on engine performance. Too low intake air temperature will increase the compression ratio of the engine, which may cause engine knock or ignition difficulties.

[0005] In this situation, the low-temperature gas in the intake system may encounter water vapor in the cold air and condense into ice, increasing the risk of icing and blockage at the intake. Furthermore, prolonged low-temperature operation may accelerate the material aging process of the EGR system and its related components. For example, the cooler's metal parts may be damaged by temperature fluctuations, and seals may harden and lose their elasticity due to low temperatures, thus affecting the EGR system's sealing and durability. In extremely low temperature conditions, the coolant inside the intercooler may freeze or freeze, causing damage to the intercooler. Bypassing the intercooler prevents the coolant from remaining inside the intercooler for an extended period of time, thereby reducing the risk of icing or freezing and protecting the intercooler's safety.

[0006] In addition, under low temperature and low load conditions, the engine's thermal efficiency may be affected. Proper intake air temperature can enable the engine to reach normal operating temperature faster, thereby improving thermal efficiency. It also helps improve the atomization effect of the fuel, promotes the complete combustion of the fuel, and further improves engine performance.

[0007] In summary, inappropriate EGR cooling and intercooling strategies in low-temperature environments can lead to a series of problems, including intake air icing, increased risk of blockage, and accelerated material aging, all of which can ultimately adversely affect vehicle dynamics. Therefore, in cold climates with low loads, it is necessary to adjust the cooling strategies of both the EGR system and the intercooler, such as reducing the amount of exhaust gas flowing through the EGR cooler or lowering the cooler's cooling efficiency to ensure that the exhaust gas maintains an appropriate temperature when it flows out of the EGR module. Summary of the Invention

[0008] In view of this, it is necessary to provide a control device for engine intercooler bypass and EGR cooler bypass to achieve the purpose of simultaneously adjusting the cooling strategies of the EGR system and the intercooler system.

[0009] In order to solve the above problems, the present invention provides a control device for engine intercooler bypass and EGR cooler bypass, comprising:

[0010] A multi-way butterfly valve is provided with at least three air flow channels, and the input end is connected to the supercharger;

[0011] An EGR cooler is provided on an EGR cooling branch, one end of the EGR cooling branch is connected to the EGR circuit, and the other end is connected to the intake manifold;

[0012] An EGR bypass branch, one end of which is connected to the EGR circuit through the first air flow channel of the multi-way butterfly valve, and the other end of which is connected to the EGR cooling branch and is located between the EGR cooler and the intake manifold;

[0013] An intercooler bypass branch, one end of which is connected to the intake manifold and the other end of which is connected to the second air flow channel of the multi-way butterfly valve;

[0014] The intercooler has one end connected to the intake manifold and the other end connected to the third air flow channel of the multi-way butterfly valve.

[0015] In a possible implementation, the EGR cooling branch is also connected to the fourth channel of the multi-way butterfly valve.

[0016] In one possible implementation, the control device for engine intercooler bypass and EGR cooler bypass further includes:

[0017] An EGR valve is provided on the EGR cooling branch and is located between the EGR cooler and the intake manifold;

[0018] The throttle valve is located at the entrance of the intake manifold.

[0019] In one possible implementation, the control device for engine intercooler bypass and EGR cooler bypass further includes:

[0020] The engine control unit is used to adjust the opening of the EGR valve based on the engine speed, load and temperature to control the recirculation amount of exhaust gas.

[0021] In one possible implementation, the engine control unit is further configured to control the opening of at least one of the first air flow channel and the second air flow channel of the multi-way butterfly valve when the ambient temperature of the engine is less than or equal to a preset temperature threshold.

[0022] In one possible implementation, the engine control unit is also used to determine the target intake temperature based on the engine operating conditions and the ambient temperature of the engine, and based on the target intake temperature and the target intercooler after-temperature, determine whether the EGR valve is closed. When the EGR valve is closed, the opening of the multi-way butterfly valve is adjusted to achieve the target intercooler after-temperature. When the EGR valve is open, the opening of the multi-way butterfly valve is adjusted to achieve the target intake temperature.

[0023] In one possible implementation, when the EGR valve is closed, adjusting the opening of the multi-way butterfly valve to achieve the target intercooler after-temperature includes:

[0024] When the EGR valve is closed, the throttle opening is determined based on the target intake volume to adjust the throttle, and the target intercooler after-temperature is determined based on the target intake temperature. With the target intercooler after-temperature as the control target, the opening of the multi-way butterfly valve is adjusted to achieve the target intercooler after-temperature.

[0025] In one possible implementation, when the EGR valve is open, adjusting the opening of the multi-way butterfly valve to achieve the target intake air temperature includes:

[0026] When the EGR valve is opened, the throttle opening and the EGR valve opening are determined based on the target intake volume to adjust the throttle and the EGR valve, and the opening of the multi-way butterfly valve is adjusted based on the preset openings of the first air flow channel and the second air flow channel, as well as the target intercooler after-temperature to achieve the target intake air temperature.

[0027] In one possible implementation, the engine control unit is further configured to:

[0028] When the ambient temperature of the engine is less than or equal to a preset temperature threshold, determining a target intake air volume, a target intake air temperature, and an opening of a second air flow passage of the multi-way butterfly valve based on the current operating condition of the engine and the ambient temperature, and determining a throttle opening and an EGR valve opening based on the target intake air volume;

[0029] Determine the target mixture temperature after the EGR cooler based on the target intake air temperature, the real-time monitored intercooler after-temperature and the EGR valve opening;

[0030] Adjust the opening of the multi-way butterfly valve to adjust the temperature after the EGR cooler to the target mixing temperature after the EGR cooler.

[0031] In one possible implementation, the engine control unit is further configured to:

[0032] When the ambient temperature of the engine is less than a preset temperature threshold, the second air flow channel of the multi-way butterfly valve is controlled to open, and when the EGR valve is not opened, the throttle opening and the target intercooler after-temperature are determined based on the current operating conditions of the engine and the ambient temperature;

[0033] Adjust the opening of the multi-way butterfly valve to achieve the target intercooler after-temperature.

[0034] The beneficial effects of adopting the above-mentioned implementation method are as follows: the control device for the engine intercooler bypass and the EGR cooler bypass provided by the present invention includes: a multi-way butterfly valve, which is provided with at least three air flow channels, and the input end is connected to the supercharger; an EGR cooler, which is arranged on the EGR cooling branch, one end of the EGR cooling branch is connected to the EGR circuit, and the other end is connected to the intake manifold; an EGR bypass branch, one end of which is connected to the EGR circuit through the first air flow channel of the multi-way butterfly valve, and the other end is connected to the EGR cooling branch and is located between the EGR cooler and the intake manifold; an intercooler bypass branch, one end of which is connected to the intake manifold, and the other end is connected to the second air flow channel of the multi-way butterfly valve; an intercooler, one end of which is connected to the intake manifold, and the other end is connected to the third air flow channel of the multi-way butterfly valve.

[0035] The present invention features a high level of integration. Designs employing multi-way butterfly valves are often more compact, enabling easier integration with other system components (such as the EGR cooler, EGR valve, and intercooler), significantly reducing the length and complexity of the bypass piping. This not only helps save valuable engine compartment space but also reduces the difficulty and cost of piping layout. This high level of integration not only reduces system complexity but also improves overall system reliability and maintainability. By tightly integrating multi-way butterfly valves, such as three-way or four-way butterfly valves, with the EGR cooler and intercooler circuits, a fully functional, compact, integrated module can be formed. This modular design simplifies the installation process and improves the overall performance and reliability of the system. It also facilitates subsequent maintenance and replacement, as the entire module can be disassembled and assembled as a single unit.

[0036] The multi-way butterfly valve can optimize engine performance: while maintaining low emissions, it optimizes the engine's combustion process by adjusting the exhaust gas recirculation volume, thereby improving fuel economy and power performance. During the low-load or cold-start phase of the engine, the exhaust gas temperature is low. If all the exhaust gas is cooled through the EGR cooler or intercooler, the gas temperature may be too low, which may lead to ice or blockage in the intake system. The multi-way butterfly valve reduces the proportion of low-temperature gas by increasing the flow rate of the bypass branch, preventing the cooling medium from staying inside the heat exchanger for a long time, thereby reducing the risk of ice or freezing and protecting the safety of components. In addition, by adjusting the temperature of the mixed gas, the multi-way butterfly valve also indirectly affects the temperature and heat capacity of the mixed gas entering the cylinder, thereby helping to optimize the combustion process and improve the engine's fuel economy and emission performance. Therefore, the present invention achieves the purpose of simultaneously adjusting the cooling strategy of the EGR system and the intercooler system by adding a multi-way butterfly valve, thereby reducing the amount of exhaust gas flowing through the EGR cooler or reducing the cooling efficiency of the cooler to ensure that the exhaust gas maintains an appropriate temperature when flowing out of the EGR module. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0038] Figure 1 A schematic structural diagram of an embodiment of a control device for engine intercooler bypass and EGR cooler bypass provided by the present invention;

[0039] Figure 2 A schematic structural diagram of another embodiment of the engine intercooler bypass and EGR cooler bypass control device provided by the present invention;

[0040] Figure 3 A flow chart of an embodiment of a method for controlling engine intercooler bypass and EGR cooler bypass provided by the present invention;

[0041] Figure 4 This is a flow chart of another embodiment of the method for controlling engine intercooler bypass and EGR cooler bypass provided by the present invention. DETAILED DESCRIPTION

[0042] The following will provide a clear and complete description of the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0043] In the description of the embodiments of the present application, unless otherwise specified, “a plurality of” means two or more.

[0044] The terms "including" and "having" and any variations thereof in the embodiments of the present invention are intended to cover non-exclusive inclusions. For example, a process, method, apparatus, product or device comprising a series of steps or modules is not necessarily limited to those steps or modules explicitly listed, but may include other steps or modules not explicitly listed or inherent to these processes, methods, products or devices.

[0045] The naming or numbering of the steps in the embodiments of the present invention does not mean that the steps in the method flow must be executed in the time / logical sequence indicated by the naming or numbering. The execution order of the named or numbered process steps can be changed according to the technical purpose to be achieved, as long as the same or similar technical effects can be achieved.

[0046] References herein to "embodiments" mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute a separate or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0047] like Figure 1 As shown, the present invention provides a control device for engine intercooler bypass and EGR cooler bypass, which includes:

[0048] The multi-way butterfly valve is provided with at least three air flow channels, and the input end is connected to the supercharger; the multi-way butterfly valve can be a three-way butterfly valve; in another embodiment, Figure 2As shown, the multi-way butterfly valve can be a four-way butterfly valve;

[0049] An EGR (Exhaust Gas Recirculation) cooler is provided on the EGR cooling branch, one end of the EGR cooling branch is connected to the EGR circuit, and the other end is connected to the intake manifold;

[0050] An EGR bypass branch, one end of which is connected to the EGR circuit through the first air flow channel of the multi-way butterfly valve, and the other end of which is connected to the EGR cooling branch and is located between the EGR cooler and the intake manifold;

[0051] An intercooler bypass branch, one end of which is connected to the intake manifold and the other end of which is connected to the second air flow channel of the multi-way butterfly valve;

[0052] The intercooler has one end connected to the intake manifold and the other end connected to the third air flow channel of the multi-way butterfly valve.

[0053] It can be understood that the multi-way butterfly valve includes: a valve body, a transmission shaft, at least three valve plates, a motor, and a cooling water jacket arranged in the valve body; the valve body is provided with air flow channels corresponding to the number of valve plates and independent of each other, and each valve plate corresponds to an air flow channel; the at least three valve plates are connected to the motor through the transmission shaft.

[0054] The first valve plate and the second valve plate have the same phase angle, and are both arranged at a 90° phase angle difference from the third valve plate; the design principle is: the two bypass branches have the same phase, the cooling branches passing through the intercooler or EGR cooler have the same phase, and the phase difference between the bypass and cooling branches is 90°.

[0055] The first valve plate is a valve plate corresponding to the first air flow channel, the second valve plate is a valve plate corresponding to the second air flow channel, and the third valve plate is a valve plate corresponding to the third air flow channel.

[0056] The control device for the engine intercooler bypass and EGR cooler bypass provided by the present invention is intended to optimize the intake air temperature and intake efficiency under low-temperature and low-load engine operating conditions. This solution allows a portion of the exhaust gas to be cooled by the EGR cooler before passing through the EGR valve, while the other portion bypasses the EGR cooler through a bypass branch and is mixed by a three-way butterfly valve upstream and downstream of the EGR cooler to precisely control the temperature and flow of the exhaust gas entering the intake manifold. Similarly, this solution allows a portion of the supercharged gas to be cooled by the intercooler before passing through the throttle valve, while the other portion bypasses the intercooler through a bypass branch and is mixed by a three-way butterfly valve downstream of the intercooler to precisely control the temperature and flow of the supercharged gas entering the intake manifold. Through the combined action of the above two methods, precise control of the overall engine intake air temperature and flow is achieved.

[0057] The working process of the control device for engine intercooler bypass and EGR cooler bypass is as follows:

[0058] Exhaust gas diversion: The exhaust gas discharged from the engine is divided into two paths at a specific location, one path enters the EGR cooler and the other path passes through the bypass branch.

[0059] Compressed gas diversion: The air after being pressurized by the supercharger is divided into two paths at a specific position, one path enters the intercooler, and the other passes through the bypass branch.

[0060] Exhaust gas cooling: The exhaust gas entering the EGR cooler exchanges heat with the coolant through the cooling pipe, and the temperature is significantly reduced.

[0061] Charged gas cooling: The charged gas entering the intercooler exchanges heat with the external environment through the cooling channel, and the temperature is significantly reduced.

[0062] Mixing of hot and cold exhaust gases: Cooled and uncooled exhaust gases are mixed at the outlet of a three-way butterfly valve downstream of the EGR cooler. The opening of the butterfly valve is adjusted according to engine operating conditions and emission requirements to optimize the mixing ratio.

[0063] Mixing of hot and cold boost gases: Cooled boost gases and uncooled boost gases are mixed at the outlet of the three-way butterfly valve. The opening of the butterfly valve is adjusted according to the engine operating conditions and ambient temperature to optimize the mixing ratio.

[0064] Exhaust Gas Recirculation: Mixed exhaust gas enters the intake manifold through the EGR valve, where it mixes with fresh air and re-enters the combustion chamber. The EGR valve opening is adjusted in real time by the engine control unit (ECU) based on parameters such as engine speed, load, and temperature to control the amount of exhaust gas recirculated.

[0065] Engine intake: The boost mixture and exhaust gas mixture, after temperature adjustment by the three-way butterfly valve, enter the engine intake manifold after flow control by the throttle valve and EGR valve respectively, and finally enter the cylinder for combustion and work.

[0066] In some embodiments, the EGR cooling branch is further connected to the fourth channel of the multi-way butterfly valve.

[0067] It can be understood that, in this embodiment, the multi-way butterfly valve is a four-way butterfly valve, and the opening of the EGR cooling branch can be adjusted by the four-way butterfly valve.

[0068] In some embodiments, the control device for engine intercooler bypass and EGR cooler bypass further includes:

[0069] An EGR valve is provided on the EGR cooling branch and is located between the EGR cooler and the intake manifold;

[0070] The throttle valve is located at the entrance of the intake manifold.

[0071] It can be understood that the EGR valve is located after the three-way butterfly valve and is used to control the amount of mixed exhaust gas entering the intake manifold.

[0072] The throttle valve is located after the three-way butterfly valve and is used to control the amount of mixed pressurized gas entering the intake manifold.

[0073] In some embodiments, the control device for engine intercooler bypass and EGR cooler bypass further includes:

[0074] The engine control unit is used to adjust the opening of the EGR valve based on the engine speed, load and temperature to control the recirculation amount of exhaust gas.

[0075] It is understood that the mixed exhaust gas enters the intake manifold through the EGR valve, mixes with fresh air, and then re-enters the combustion chamber. The opening of the EGR valve is adjusted in real time by the engine control unit based on parameters such as engine speed, load, and temperature to control the amount of exhaust gas recirculation.

[0076] In some embodiments, the engine control unit is further configured to control the opening of at least one of the first air flow channel and the second air flow channel of the multi-way butterfly valve when the ambient temperature of the engine is less than or equal to a preset temperature threshold.

[0077] It can be understood that the preset temperature threshold can be 0°C. When the EGR bypass and the intercooler bypass are controlled in linkage, when the ambient temperature of the engine is less than or equal to the preset temperature threshold, the engine control unit controls the first air flow channel and the second air flow channel of the multi-way butterfly valve to be closed.

[0078] When the EGR bypass and the intercooler bypass are independently controlled, when the ambient temperature of the engine is less than or equal to the preset temperature threshold, the engine control unit controls the first air flow channel of the multi-way butterfly valve to open and the second air flow channel to close.

[0079] In some embodiments, the engine control unit is also used to determine the target intake temperature based on the engine operating conditions and the ambient temperature of the engine, and to determine whether the EGR valve is closed based on the target intake temperature and the target intercooler after-temperature. When the EGR valve is closed, the opening of the multi-way butterfly valve is adjusted to achieve the target intercooler after-temperature. When the EGR valve is open, the opening of the multi-way butterfly valve is adjusted to achieve the target intake temperature.

[0080] In some embodiments, when the EGR valve is closed, adjusting the opening of the multi-way butterfly valve to achieve a target intercooler after-temperature includes:

[0081] When the EGR valve is closed, the throttle opening is determined based on the target intake volume to adjust the throttle, and the target intercooler after-temperature is determined based on the target intake temperature. With the target intercooler after-temperature as the control target, the opening of the multi-way butterfly valve is adjusted to achieve the target intercooler after-temperature.

[0082] In some embodiments, when the EGR valve is open, adjusting the opening of the multi-way butterfly valve to achieve a target intake air temperature includes:

[0083] When the EGR valve is opened, the throttle opening and the EGR valve opening are determined based on the target intake volume to adjust the throttle and the EGR valve, and the opening of the multi-way butterfly valve is adjusted based on the preset openings of the first air flow channel and the second air flow channel, as well as the target intercooler after-temperature to achieve the target intake air temperature (intake air temperature target value).

[0084] In some embodiments, the engine control unit is further configured to:

[0085] When the ambient temperature of the engine is less than or equal to a preset temperature threshold, determining a target intake air volume, a target intake air temperature, and an opening of a second air flow passage of the multi-way butterfly valve based on the current operating condition of the engine and the ambient temperature, and determining a throttle opening and an EGR valve opening based on the target intake air volume;

[0086] Determine the target mixture temperature after the EGR cooler based on the target intake air temperature, the real-time monitored intercooler after-temperature and the EGR valve opening;

[0087] Adjust the opening of the multi-way butterfly valve to adjust the temperature after the EGR cooler to the target mixing temperature after the EGR cooler.

[0088] In some embodiments, the engine control unit is further configured to:

[0089] When the ambient temperature of the engine is less than a preset temperature threshold, the second air flow channel of the multi-way butterfly valve is controlled to open, and when the EGR valve is not opened, the throttle opening and the target intercooler after-temperature are determined based on the current operating conditions of the engine and the ambient temperature;

[0090] Adjust the opening of the multi-way butterfly valve to achieve the target intercooler after-temperature.

[0091] In some embodiments, the control device for engine intercooler bypass and EGR cooler bypass specifically includes:

[0092] EGR cooler: Responsible for cooling part of the exhaust gas discharged from the engine, reducing its temperature to reduce the generation of nitrogen oxides (NOx).

[0093] EGR bypass branch: provides a channel for uncooled exhaust gas to bypass the EGR cooler.

[0094] Intercooler: Responsible for cooling the high-temperature and high-pressure gas from the supercharger, reducing its density and increasing the engine's air intake.

[0095] Intercooler bypass branch: provides a channel for uncooled pressurized gas to bypass the intercooler.

[0096] Multi-way butterfly valves, such as three-way butterfly valves, are installed downstream / upstream of the EGR cooler and intercooler. They are divided into two chambers: one for regulating the mixture ratio of cooled and uncooled exhaust gas, and the other for regulating the mixture ratio of cooled and uncooled boost gas. The degree of opening of the butterfly valve determines the mixture ratio of the hot and cold gases. Features of two-way butterfly valves include a valve body made of corrosion-resistant, high-temperature materials to withstand the high-temperature and high-pressure environments of exhaust and boost gas. The butterfly disc, as a control element, rotates to adjust the opening of the channel, thereby regulating the exhaust gas flow. The edge of the butterfly disc is typically specially treated to reduce fluid resistance and improve sealing performance. A sealing ring or gasket is placed between the butterfly disc and the valve seat to effectively prevent exhaust gas leakage when closed. The butterfly valve's actuator (e.g., electric, pneumatic, or hydraulic) receives signals from the engine control unit (ECU) to precisely control the rotation angle of the butterfly disc, achieving precise regulation of exhaust flow.

[0097] The three-way butterfly valve used in this invention consists of a valve body, a drive shaft, three valve discs (first, second, and third), a motor, and a cooling water jacket housed within the valve body. The valve body features three independent airflow channels, each corresponding to a valve disc. The valve discs are connected to the motor via a drive shaft for synchronous control. The first and second valve discs have the same phase angle, while the third valve disc is positioned 90° apart. This ensures that, by default, the first channel's valve disc is fully open, while the second and third channels' valve discs are fully closed.

[0098] Single drive shaft control: One drive shaft is used to simultaneously control the opening and closing of three valve plates, driven by a single motor, which simplifies the structure, reduces costs and improves reliability.

[0099] Cooling channel design: A cooling water jacket is provided inside the valve body. By circulating cooling water, the high-temperature gas flowing through the valve body is cooled or the low-temperature gas is kept warm, thus expanding the application range of the valve.

[0100] Flexible opening adjustment: Through the precise control of the motor, all valves can be adjusted to any opening between fully closed and fully open, including half-open state, to meet the gas flow requirements under different working conditions.

[0101] Variable channel diameter: According to actual usage, channels of different diameters can be selected to optimize gas flow resistance and improve throttling efficiency.

[0102] EGR valve: Located after the three-way butterfly valve, it controls the amount of mixed exhaust gas entering the intake manifold.

[0103] Throttle: Located after the three-way butterfly valve, it controls the amount of mixed pressurized gas entering the intake manifold.

[0104] like Figure 3 As shown in the figure, the control method of engine intercooler bypass and EGR cooler bypass can be summarized as follows:

[0105] ①Ambient temperature judgment:

[0106] First, the system detects the current ambient temperature T amb If T amb If the ambient temperature is ≤ 0°C, special condition processing is performed: the intercooler bypass is turned on to ensure that the cooling effect does not affect engine operation due to the low ambient temperature; at the same time, the EGR system is turned on by default to optimize combustion efficiency in low temperature environments.

[0107] ②Determine target parameters:

[0108] According to the current engine operating conditions (such as speed, load, etc.) and ambient temperature T amb , determine the target intake air volume and intake air temperature target value T1. At the same time, the intercooler bypass is adjusted to the preset opening K1 And EGR bypass is adjusted to the preset opening K2 , (K1 = K2 ).

[0109] ③EGR valve opening judgment:

[0110] Detect whether the engine has EGR valve opening requirements under the current working conditions. If the EGR valve is closed, the intake air temperature target value T1 = Target intercooler after-temperature T2 , enters closed-loop control A with the intercooler after-temperature as the control target; if the EGR valve is open, the intake air temperature target value T1 =f(T2 , T3 , K1 , K2 ), enters closed-loop control B with the intercooling after-temperature as the control target;

[0111] ④ Intake air temperature model: Using one-dimensional simulation software and relevant test data, the mathematical relationship between the engine intake air temperature and the three-way butterfly valve opening (i.e., EGR cooler bypass / intercooler bypass degree) under different operating conditions is constructed: T1=f(T2 , T3 , K1 , K2 ), and estimates the exact temperature of the engine intake air using only existing sensor data and hardware status.

[0112] ⑤Intercooler bypass control (closed loop control A):

[0113] Achieve target intercooler after-temperature T2 by opening the three-way butterfly valve PID parameters: CURVE throttle valve temperature

[0114] ⑥Intercooler bypass & EGR cooler bypass control (closed loop control B):

[0115] Achieve target intake air temperature T1 by opening the three-way butterfly valve , PID parameters: CURVE intake temperature = f(T2 , T3 , K1 , K2 )

[0116] ⑦Continuous monitoring and adjustment:

[0117] During the entire process, the system will continuously monitor key parameters such as ambient temperature, intake temperature, intercooler temperature, and EGR cooler temperature, and dynamically adjust the throttle opening K3, intercooler bypass opening K1, and EGR valve opening K4 as needed to ensure that the engine can achieve optimal fuel economy and emission performance under various operating conditions.

[0118] Control strategy 2 (EGR bypass and intercooler bypass can be controlled independently)

[0119] like Figure 4 As shown, the specific control method can be summarized into the following steps:

[0120] ①Ambient temperature judgment:

[0121] First, the system detects the current ambient temperature T amb If T amb If the ambient temperature is ≤ 0°C, special condition processing is performed: the intercooler bypass is turned on to ensure that the cooling effect does not affect engine operation due to the low ambient temperature; at the same time, the EGR system is turned on by default to optimize combustion efficiency in low temperature environments.

[0122] ②Determine target parameters:

[0123] According to the current engine operating conditions (such as speed, load, etc.) and ambient temperature T amb, determining the target intake air volume and intake air temperature target value T1. Simultaneously, the decision is made whether the EGR system needs to be activated. Since there is no linkage between the EGR channel and the intercooler channel valve plate within the three-way butterfly valve, if activated, T1 is precisely controlled by the EGR bypass circuit, and the intercooler bypass opening K2 remains unchanged. If not activated, the intercooler bypass opening K2 changes in real time, while T1 is precisely controlled by the intercooler bypass circuit, and the EGR valve remains closed.

[0124] ③Throttle and EGR valve opening adjustment:

[0125] Based on the determined target intake air volume and the current ambient temperature T amb First, the throttle valve opening K1 is calculated and adjusted to meet the target intake air volume. Next, based on the actual intercooler temperature T2 and other relevant factors (such as exhaust temperature and exhaust pressure), the EGR valve opening K3 is calculated and adjusted to control the flow rate of recirculated exhaust gas.

[0126] ④Intercooler bypass control:

[0127] For intercooler bypass, if the ambient temperature is below 0°C and the system needs to adjust the intercooler temperature (T2), the opening of the three-way butterfly valve or four-way butterfly valve (intercooler bypass side) is controlled through a closed loop to achieve the target mixing temperature T2 , thereby reaching the target intake air temperature T1.

[0128] ⑤ EGR cooler bypass control:

[0129] For the EGR cooler bypass, the opening of the three-way butterfly valve or four-way butterfly valve (EGR bypass side) is also controlled through closed-loop control. According to the intake temperature target value T1, the real-time monitored intercooler temperature T2, and the EGR valve opening K3, the temperature after the EGR cooler is inferred and the bypass amount is adjusted to achieve the target mixing temperature T3, optimize the temperature of the EGR exhaust gas, and improve combustion efficiency.

[0130] ⑥Continuous monitoring and adjustment:

[0131] During the entire process, the system will continuously monitor key parameters such as ambient temperature, intake temperature, intercooler temperature, and EGR cooler temperature, and dynamically adjust the throttle opening K1, intercooler bypass opening K2 (if the intercooler bypass is not closed), and EGR valve opening K3 as needed to ensure that the engine can achieve optimal fuel economy and emission performance under various operating conditions.

[0132] The present invention features a high level of integration. Designs employing multi-way butterfly valves, such as three-way or four-way butterfly valves, are often more compact, enabling easier integration with other system components (such as the EGR cooler, EGR valve, and intercooler), significantly reducing the length and complexity of the bypass piping. This not only helps save valuable engine compartment space but also reduces the difficulty and cost of piping layout. This high level of integration not only reduces system complexity but also improves overall system reliability and maintainability. By tightly integrating multi-way butterfly valves, such as three-way or four-way butterfly valves, with the EGR cooler and intercooler circuits, a fully functional, compact integrated module is formed. This modular design simplifies the installation process and improves the overall performance and reliability of the system. It also facilitates subsequent maintenance and replacement, as the entire module can be disassembled and assembled as a single unit.

[0133] While two traditional solenoid valves can function in an EGR bypass system, their size and shape may limit tight integration with other components, impacting the overall system layout and efficiency. Traditional solenoid valves may require additional piping and fittings to connect the EGR cooler and EGR valve, increasing system complexity and footprint. The typically loose connection between traditional solenoid valves and the EGR cooler makes it difficult to achieve a high degree of modularity. This can lead to increased time and labor required during installation, maintenance, and replacement.

[0134] In addition, multi-way butterfly valves such as three-way butterfly valves or four-way butterfly valves have better flow regulation performance and can more accurately control the mixing ratio of hot and cold gases in different air chambers and the amount of exhaust gas recirculation. Simple structure, high reliability, and reduced cost: The design of one drive shaft controlling three or four valve plates greatly simplifies the structure, improves the reliability and stability of the system, and reduces manufacturing costs compared to the traditional method of independent control of multiple valve plates. Wide range of applications: The integrated cooling function enables the throttle valve to handle high-temperature and low-temperature gases at the same time, broadening its scope of application. Small gas flow resistance: By adjusting the channel diameter and the valve plate opening, precise control of the gas flow resistance can be achieved, thereby improving throttling efficiency.

[0135] This is crucial for optimizing engine performance and reducing emissions. The exhaust gas in the EGR system is hot and may contain corrosive substances. Multi-way butterfly valves such as three-way butterfly valves or four-way butterfly valves are usually made of high-temperature and corrosion-resistant materials to ensure long-term stable operation.

[0136] The present invention has the following beneficial effects:

[0137] Improve emission performance: Effectively reduce NOx emissions by precisely controlling the mixing ratio and recirculation volume of exhaust gases.

[0138] Optimizing Engine Performance: While maintaining low emissions, the engine's combustion process is optimized by adjusting the exhaust gas recirculation rate, improving fuel economy and power performance. During low engine load or cold start phases, exhaust gas temperatures are low. If all exhaust gas passes through the EGR cooler or intercooler, the gas temperature may be too low, leading to ice formation or blockage in the intake system. The three-way butterfly valve increases the flow rate of the bypass branch, reducing the proportion of low-temperature gas and preventing the cooling medium from remaining in the heat exchanger for a long time, thereby reducing the risk of ice or freezing and protecting component safety. Furthermore, by regulating the temperature of the mixed gas, the three-way butterfly valve indirectly affects the temperature and heat capacity of the mixed gas entering the cylinder, thereby helping to optimize the combustion process and improve the engine's fuel economy and emissions performance.

[0139] Enhanced system flexibility: This technical solution allows flexible adjustment of intake and exhaust gas treatment strategies according to different engine operating conditions and emission requirements.

[0140] By bypassing the intercooler, the pressurized air can bypass the intercooler and enter the engine directly, thus avoiding the problem of too low intake temperature.

[0141] The above is a detailed introduction to the control device for the engine intercooler bypass and EGR cooler bypass provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the ideas of the present invention, there may be changes in the specific implementation methods and application scopes. In summary, the contents of this specification should not be understood as limiting the present invention.

Claims

1. A control device for engine intercooler bypass and EGR cooler bypass, characterized in that: include: A multi-way butterfly valve is provided with at least three air flow channels, and the input end is connected to the supercharger; An EGR cooler is provided on an EGR cooling branch, one end of the EGR cooling branch is connected to the EGR circuit, and the other end is connected to the intake manifold; An EGR bypass branch, one end of which is connected to the EGR circuit through the first air flow channel of the multi-way butterfly valve, and the other end of which is connected to the EGR cooling branch and is located between the EGR cooler and the intake manifold; An intercooler bypass branch, one end of which is connected to the intake manifold and the other end of which is connected to the second air flow channel of the multi-way butterfly valve; The intercooler has one end connected to the intake manifold and the other end connected to the third air flow channel of the multi-way butterfly valve.

2. The engine intercooler bypass and EGR cooler bypass control device according to claim 1, characterized in that: The EGR cooling branch is also connected to the fourth channel of the multi-way butterfly valve.

3. The engine intercooler bypass and EGR cooler bypass control device according to claim 1, characterized in that: Also includes: An EGR valve is provided on the EGR cooling branch and is located between the EGR cooler and the intake manifold; The throttle valve is located at the entrance of the intake manifold.

4. The engine intercooler bypass and EGR cooler bypass control device according to claim 3, characterized in that: Also includes: The engine control unit is used to adjust the opening of the EGR valve based on the engine speed, load and temperature to control the recirculation amount of exhaust gas.

5. The engine intercooler bypass and EGR cooler bypass control device according to claim 4, characterized in that: The engine control unit is further used to control at least one of the first air flow channel and the second air flow channel of the multi-way butterfly valve to open when the ambient temperature of the engine is less than or equal to a preset temperature threshold.

6. The engine intercooler bypass and EGR cooler bypass control device according to claim 4, characterized in that: The engine control unit is also used to determine the target intake temperature based on the engine operating conditions and the ambient temperature of the engine, and to determine whether the EGR valve is closed based on the target intake temperature and the target intercooler after-temperature. When the EGR valve is closed, the opening of the multi-way butterfly valve is adjusted to achieve the target intercooler after-temperature. When the EGR valve is open, the opening of the multi-way butterfly valve is adjusted to achieve the target intake temperature.

7. The engine intercooler bypass and EGR cooler bypass control device according to claim 6, characterized in that: When the EGR valve is closed, adjust the opening of the multi-way butterfly valve to achieve the target intercooler after-temperature, including: When the EGR valve is closed, the throttle opening is determined based on the target intake volume to adjust the throttle, and the target intercooler after-temperature is determined based on the target intake temperature. With the target intercooler after-temperature as the control target, the opening of the multi-way butterfly valve is adjusted to achieve the target intercooler after-temperature.

8. The engine intercooler bypass and EGR cooler bypass control device according to claim 6, characterized in that: When the EGR valve is open, adjust the opening of the multi-way butterfly valve to achieve the target intake air temperature, including: When the EGR valve is opened, the throttle opening and the EGR valve opening are determined based on the target intake volume to adjust the throttle and the EGR valve, and the opening of the multi-way butterfly valve is adjusted based on the preset openings of the first air flow channel and the second air flow channel, as well as the target intercooler after-temperature to achieve the target intake air temperature.

9. The engine intercooler bypass and EGR cooler bypass control device according to claim 4, characterized in that: Engine control unit, also used for: When the ambient temperature of the engine is less than or equal to a preset temperature threshold, determining a target intake air volume, a target intake air temperature, and an opening of a second air flow passage of the multi-way butterfly valve based on the current operating condition of the engine and the ambient temperature, and determining a throttle opening and an EGR valve opening based on the target intake air volume; Determine the target mixture temperature after the EGR cooler based on the target intake air temperature, the real-time monitored intercooler after-temperature and the EGR valve opening; Adjust the opening of the multi-way butterfly valve to adjust the temperature after the EGR cooler to the target mixing temperature after the EGR cooler.

10. The engine intercooler bypass and EGR cooler bypass control device according to claim 4, characterized in that: Engine control unit, also used for: When the ambient temperature of the engine is less than a preset temperature threshold, the second air flow channel of the multi-way butterfly valve is controlled to open, and when the EGR valve is not opened, the throttle opening and the target intercooler after-temperature are determined based on the current operating conditions of the engine and the ambient temperature; Adjust the opening of the multi-way butterfly valve to achieve the target intercooler after-temperature.

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