Asymmetric turbocharger, method for controlling degree of asymmetry, and storage medium

Abstract

The invention provides an asymmetric turbocharger, an asymmetry degree control method and a storage medium, and belongs to the technical field of engines. The asymmetric turbocharger includes a turbine, a stepping motor, and a controller. A first flow channel and a second flow channel are arranged in a volute of the turbine, the first flow channel and the second flow channel are communicated with an exhaust port of the engine, the flow area of the first flow channel is fixed, the flow area of the second flow channel is adjustable, and a first side of a shell of the second flow channel and a shell of the first flow channel are of an integrated structure; the stepping motor is used for controlling the displacement of the second side of the shell of the second flow channel so as to adjust the flow area of the second flow channel; the controller is in communication connection with the engine and the stepping motor and used for receiving working condition parameters of the engine and controlling the stepping motor to adjust the flow area of the second flow channel based on the working condition parameters so as to control the asymmetry degree between the first flow channel and the second flow channel to reach the target asymmetry degree. The problem that the pumping loss is large due to the asymmetric turbocharger at the high rotating speed is solved.

Description

Technical Field

[0001] This application relates to the field of engine technology, and more specifically, to an asymmetric turbocharger, a method for controlling asymmetry, and a computer-readable storage medium. Background Technology

[0002] To achieve efficient EGR flow, especially at low engine speeds, a sufficient pressure differential needs to be established in the EGR circuit. To address this requirement, asymmetric turbochargers are commonly used.

[0003] Existing asymmetric turbochargers pose a risk of turbine overspeed and increased back pressure at high speeds, which increases pumping losses. Summary of the Invention

[0004] The main objective of this application is to provide an asymmetric turbocharger, an asymmetry control method, and a computer-readable storage medium to at least solve the problem of large pumping losses caused by asymmetric turbochargers at high speeds in the prior art.

[0005] To achieve the above objectives, according to one aspect of this application, an asymmetric turbocharger is provided, comprising: a turbine, wherein a first flow channel and a second flow channel are provided within the turbine housing, the first flow channel and the second flow channel are connected to the exhaust port of an engine, the flow area of ​​the first flow channel is fixed, the flow area of ​​the second flow channel is adjustable within a preset range, the housing of the second flow channel is split, and a first side of the housing of the second flow channel is integrally formed with the housing of the first flow channel; a stepper motor, the stepper motor being connected to a second side of the housing of the second flow channel via a connecting shaft, for controlling the displacement of the second side of the housing of the second flow channel to adjust the flow area of ​​the second flow channel; and a controller, the controller being communicatively connected to the engine and the stepper motor, for receiving the operating parameters of the engine, and controlling the stepper motor to adjust the flow area of ​​the second flow channel based on the operating parameters and a preset engine operating condition and asymmetry mapping table, so as to control the asymmetry between the first flow channel and the second flow channel to reach a target asymmetry, wherein the asymmetry is the ratio of the flow area of ​​the second flow channel to the flow area of ​​the first flow channel.

[0006] Optionally, the asymmetric turbocharger further includes a displacement sensor disposed on the housing of the first flow channel, for detecting displacement information on the second side of the housing of the second flow channel, and transmitting the displacement information to the controller.

[0007] Optionally, the turbine casing includes an annular groove disposed on the second side of the casing of the second flow channel, and the annular groove is provided with a guide mechanism for controlling the second side of the casing of the second flow channel to move along the first direction of the annular groove, wherein the first direction of the annular groove is perpendicular to the axial centerline of the second flow channel.

[0008] Optionally, the asymmetric turbocharger further includes a compressor connected to the turbine.

[0009] Optionally, the asymmetric turbocharger further includes a bypass pipe with a bleed valve for discharging exhaust gases from the first and second flow channels to the turbine to reduce the turbine's rotational speed.

[0010] According to another aspect of this application, a method for controlling the asymmetry of an asymmetric turbocharger as described in any of the above-described methods is provided, comprising: acquiring engine operating parameters, the operating parameters including engine speed and cyclic fuel injection quantity; determining a target asymmetry corresponding to the operating parameters by means of a preset engine operating condition-asymmetry mapping table based on the operating parameters; controlling a stepper motor to adjust the displacement of a second side of the housing of the second flow channel to adjust the flow area of ​​the second flow channel so that the asymmetry between the first flow channel and the second flow channel reaches the target asymmetry, wherein the asymmetry is the ratio of the flow area of ​​the second flow channel to the flow area of ​​the first flow channel.

[0011] Optionally, before determining the target asymmetry corresponding to the operating condition parameters through a preset engine operating condition and asymmetry mapping table based on the operating condition parameters, the method further includes: performing performance simulations on different engine operating conditions to determine the target EGR rate under the different engine operating conditions; adjusting the flow area of ​​the second flow channel based on the target EGR rate to obtain the target flow area of ​​the second flow channel under the different engine operating conditions, and determining the target displacement signal corresponding to the target flow area of ​​the second flow channel; determining the asymmetry under the different engine operating conditions based on the target flow area of ​​the second flow channel and the flow area of ​​the first flow channel; and constructing the preset engine operating condition and asymmetry mapping table based on the asymmetry under the different engine operating conditions and the target displacement signal.

[0012] Optionally, controlling the stepper motor to adjust the displacement of the second side of the housing of the second flow channel to adjust the flow area of ​​the second flow channel so that the asymmetry between the first flow channel and the second flow channel reaches the target asymmetry, wherein the asymmetry is the ratio of the flow area of ​​the second flow channel to the flow area of ​​the first flow channel, includes: matching the target asymmetry and target displacement signal corresponding to the current operating parameters of the engine from the preset engine operating condition and asymmetry mapping table; comparing the target asymmetry with the current asymmetry to determine the displacement adjustment signal of the second side of the housing of the second flow channel; and controlling the stepper motor to adjust the displacement of the second side of the housing of the second flow channel according to the displacement adjustment signal to adjust the flow area of ​​the second flow channel.

[0013] Optionally, comparing the target asymmetry with the current asymmetry to determine the displacement adjustment signal of the second side of the housing of the second flow channel includes: determining whether the flow area of ​​the second flow channel is consistent with the flow area of ​​the second flow channel corresponding to the target asymmetry; if the flow area of ​​the second flow channel is inconsistent with the flow area of ​​the second flow channel corresponding to the target asymmetry, then determining the displacement signal of the second flow channel corresponding to the target asymmetry as the displacement adjustment signal.

[0014] According to another aspect of this application, a computer-readable storage medium is provided, the computer-readable storage medium including a stored program, wherein, when the program is executed, it controls the device where the computer-readable storage medium is located to perform any of the aforementioned asymmetric degree control methods.

[0015] According to the technical solution of this application, the asymmetric turbocharger includes a turbine, a stepper motor, and a controller. The turbine's volute housing has a first flow channel and a second flow channel, which connect to the engine's exhaust port. The flow area of ​​the first flow channel is fixed, while the flow area of ​​the second flow channel is adjustable within a preset range. The housing of the second flow channel is a split type, with the first side of the second flow channel housing being an integral structure with the first flow channel housing. The stepper motor is connected to the second side of the second flow channel housing via a connecting shaft and is used to control the displacement of the second side of the second flow channel housing to adjust the flow area of ​​the second flow channel. The controller is communicatively connected to the engine and the stepper motor, receiving engine operating parameters and controlling the stepper motor to adjust the flow area of ​​the second flow channel based on the operating parameters and a preset mapping table between engine operating conditions and asymmetry, thereby controlling the asymmetry between the first and second flow channels to achieve a target asymmetry, where the asymmetry is the ratio of the flow area of ​​the second flow channel to the flow area of ​​the first flow channel. In this solution, by combining a first flow channel with a fixed flow area and a second flow channel with an adjustable flow area, the asymmetry of the turbocharger is dynamically adjusted. By controlling the displacement of the second side of the housing of the second flow channel through a stepper motor, the flow area of ​​the second flow channel can be adjusted according to the actual operating conditions of the engine. This can reduce pumping losses at high speeds or low EGR requirements, thereby solving the problem of large pumping losses caused by asymmetric turbochargers at high speeds. Attached Figure Description

[0016] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0017] Figure 1 A schematic diagram of an asymmetric turbocharger provided in an embodiment of this application is shown;

[0018] Figure 2 A schematic diagram of a symmetry adjustment structure for an asymmetric turbocharger provided in an embodiment of this application is shown;

[0019] Figure 3 A flowchart illustrating a method for controlling asymmetry according to an embodiment of this application is shown.

[0020] Figure 4 A schematic diagram of a specific asymmetric turbocharger provided in an embodiment of this application is shown;

[0021] Figure 5 A schematic diagram of another asymmetric turbocharger symmetry adjustment structure provided in an embodiment of this application is shown;

[0022] Figure 6A control logic diagram of a specific asymmetric turbocharger provided in an embodiment according to this application is shown;

[0023] Figure 7 A structural block diagram of an asymmetry control device according to an embodiment of this application is shown.

[0024] The above figures include the following reference numerals:

[0025] 01. Asymmetric turbocharger; 10. Turbine; 101. First flow channel; 102. Second flow channel; 103. Annular groove; 20. Stepper motor; 30. Controller; 40. Engine; 50. Displacement sensor. Detailed Implementation

[0026] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0027] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.

[0028] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present application described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0029] As described in the background section, existing asymmetric turbochargers pose risks of turbine overspeed and increased back pressure at high speeds, increasing pumping losses. To address the issue of high pumping losses caused by asymmetric turbochargers at high speeds, embodiments of this application provide an asymmetric turbocharger, a method for controlling asymmetry, and a computer-readable storage medium.

[0030] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0031] Figure 1 This is a schematic diagram of an asymmetric turbocharger provided in an embodiment of this application, as shown below. Figure 1 As shown, the asymmetric turbocharger 01 includes a turbine 10, a stepper motor 20, and a controller 30. The turbine 10 has a first flow channel 101 and a second flow channel 102 within its casing. The first and second flow channels connect to the exhaust port of the engine 40. The flow area of ​​the first flow channel 101 is fixed, while the flow area of ​​the second flow channel 102 is adjustable within a preset range. The casing of the second flow channel 102 is a split type, with the first side of the casing of the second flow channel 102 being an integral structure with the casing of the first flow channel 101. The stepper motor 20 is connected to the second side of the casing of the second flow channel 102 via a connecting shaft and is used to control the flow area of ​​the second flow channel 102. The displacement on both sides is used to adjust the flow area of ​​the second flow channel 102; the controller 30 is communicatively connected to the engine 40 and the stepper motor 20, and is used to receive the operating parameters of the engine 40, and control the stepper motor 20 to adjust the flow area of ​​the second flow channel 102 based on the operating parameters and the preset engine operating condition and asymmetry mapping table, so as to control the asymmetry between the first flow channel 101 and the second flow channel 102 to reach the target asymmetry, wherein the asymmetry is the ratio of the flow area of ​​the second flow channel 102 to the flow area of ​​the first flow channel 101.

[0032] Specifically, the asymmetric turbocharger of this application is characterized by its ability to dynamically adjust the asymmetry to adapt to the engine's needs under different operating conditions. This asymmetric turbocharger mainly comprises three key components: a turbine, a stepper motor, and a controller. The turbine's volute housing has two flow channels: a first flow channel and a second flow channel, both of which are connected to the engine's exhaust port. The flow area of ​​the first flow channel is fixed, while the flow area of ​​the second flow channel can be adjusted within a certain preset range. The housing of the second flow channel is designed as a split structure; the first side is an integral structure with the housing of the first flow channel, while the second side is connected to the stepper motor via a connecting shaft. The stepper motor adjusts the flow area of ​​the second flow channel by controlling the displacement of the second side of the second flow channel. When the motor drives the second side of the housing of the second flow channel to move, it changes the size of the flow area of ​​the second flow channel, thereby affecting the exhaust flow rate passing through it.

[0033] The controller communicates with the engine and the stepper motor, receives real-time operating parameters from the engine (such as engine speed and fuel injection volume), and controls the stepper motor's movement by analyzing these parameters and a preset mapping table between engine operating conditions and asymmetry. This adjusts the flow area of ​​the second flow channel, with the ultimate goal of optimizing the asymmetry between the first and second flow channels, i.e., the target asymmetry, which is the ratio of the flow area of ​​the second flow channel to the flow area of ​​the first flow channel.

[0034] The structural design and control logic of the asymmetric turbocharger in this embodiment enhance its flexibility and efficiency. Under low-speed conditions, the controller can control the stepper motor to reduce the flow area of ​​the second flow channel, increasing the turbine inlet pressure and thus increasing EGR flow to meet emission requirements. At high speeds or when EGR demand is low, the controller controls the stepper motor to increase the flow area of ​​the second flow channel, reducing exhaust back pressure, minimizing pumping losses, and improving fuel economy. Furthermore, by monitoring and adjusting the asymmetry in real time, reliability issues caused by high back pressure, such as seal failure, can be avoided, ensuring the safe and stable operation of the turbocharger and engine.

[0035] By combining a first flow channel with a fixed flow area and a second flow channel with an adjustable flow area, dynamic adjustment of the turbocharger's asymmetry is achieved. By controlling the displacement of the second side of the second flow channel's housing using a stepper motor, the flow area of ​​the second flow channel can be adjusted according to the engine's actual operating conditions, reducing pumping losses at high speeds or low EGR requirements. In short, the asymmetric turbocharger of this embodiment, through its adjustable flow area design and control logic, achieves adaptive adjustment of asymmetry under different engine operating conditions, thereby optimizing the EGR system's efficiency and solving the problem of large pumping losses caused by asymmetric turbochargers at high speeds.

[0036] In some embodiments of this application, such as Figure 1 As shown, the asymmetric turbocharger 01 also includes a displacement sensor 50, which is disposed on the housing of the first flow channel 101 and is used to detect the displacement information of the second side of the housing of the second flow channel 102 and transmit the displacement information to the controller 30.

[0037] Specifically, a displacement sensor is installed on the housing of the first flow channel to detect changes in displacement on the second side of the housing of the second flow channel. Displacement refers to the distance the second side of the housing of the second flow channel moves relative to the stationary first side of the housing under the action of the stepper motor. The displacement sensor collects the displacement information of the second side of the housing of the second flow channel in real time. This displacement information affects the size of the flow area of ​​the second flow channel, as the size of the flow area directly determines the state of asymmetry. Based on the received displacement information and the real-time operating parameters of the engine, the controller can determine whether the current asymmetry meets the predetermined target value.

[0038] By employing displacement sensors, asymmetric turbochargers can achieve more accurate monitoring and adjustment, improving response speed and control precision. This is particularly important for maintaining optimal EGR efficiency and emission control under different engine operating conditions. Displacement sensors allow for timely adjustment of the flow area of ​​the second flow channel, even under extreme or rapidly changing conditions, to achieve ideal asymmetry. This optimizes engine performance, improves fuel economy, and reduces unnecessary pumping losses while avoiding safety issues such as seal failure caused by high back pressure. In short, the introduction of displacement sensors gives asymmetric turbochargers greater adaptability and stability, enabling more precise control of asymmetry to meet the demands of complex engine conditions and ensuring efficient and reliable operation of the EGR system throughout the entire engine operating range.

[0039] In some embodiments of this application, such as Figure 2 As shown, the volute of the turbine 10 includes an annular groove 103, which is disposed on the second side of the housing of the second flow channel 102. The annular groove 103 is provided with a guide mechanism for controlling the second side of the housing of the second flow channel 102 to move along the first direction of the annular groove 103. The first direction of the annular groove 103 is perpendicular to the axial centerline of the second flow channel 102.

[0040] Specifically, the annular groove and the guide mechanism together ensure stable and directional displacement of the second side of the second flow channel housing, enabling precise control of the flow area of ​​the second flow channel. The annular groove is located on the second side of the second flow channel housing and extends in a direction perpendicular to the axial centerline of the second flow channel. The design of the annular groove allows the second side of the second flow channel housing to move linearly within the groove without affecting the structural integrity of the entire turbocharger or the normal operation of the turbine. The guide mechanism, located inside the annular groove, guides and constrains the movement path of the second side of the second flow channel housing. Through the guide mechanism, it is ensured that the displacement of the second side of the second flow channel housing completely follows the first direction set by the annular groove, preventing deviation or jamming during displacement and guaranteeing the smoothness and accuracy of the displacement process.

[0041] The combination of the annular groove and the guide mechanism not only provides the physical track for the displacement of the second side of the second flow channel housing, but also ensures the stability and precision of the structure during displacement, which is key to achieving dynamic asymmetry adjustment. Specifically, under the action of the stepper motor, the second side of the second flow channel housing can move smoothly within the annular groove, thereby precisely adjusting the flow area of ​​the second flow channel to optimize asymmetry and adapt to the needs of different engine operating conditions. The guide mechanism further enhances the controllability of the displacement, avoiding potential mechanical failures under high-speed or frequently changing load conditions, such as housing jamming and increased frictional losses, thus improving the durability and response speed of the turbocharger.

[0042] In some embodiments of this application, the asymmetric turbocharger further includes a compressor connected to the turbine.

[0043] Specifically, the compressor is one of the core components of an asymmetric turbocharger, connected to the turbine and sharing a rotating shaft. The compressor's function is to use the mechanical energy generated by the turbine's rotation to compress the air entering the cylinders, thereby increasing the engine's intake pressure. When the turbine impeller rotates due to exhaust pressure, kinetic energy is transferred to the compressor impeller via the shaft. The compressor then rotates, drawing in outside air and compressing it to a higher density before sending it into the engine's intake manifold. This design improves the quality of air entering the cylinders, thus increasing the engine's combustion efficiency and power output, while also improving fuel economy.

[0044] In an asymmetric turbocharger, the compressor and turbine interact. By adjusting the flow area of ​​the turbine's second flow channel, the asymmetry is altered, directly affecting the exhaust flow and pressure reaching the turbine, and consequently, the compressor's intake pressure and flow. This synergistic effect allows the engine to dynamically adjust intake pressure and EGR (exhaust gas recirculation) rate according to actual operating conditions, achieving a balance between emission control and performance optimization. For example, under low-speed, high-load conditions, reducing the flow area of ​​the second flow channel (i.e., reducing asymmetry) increases the turbine inlet pressure, promoting more exhaust gas recirculation, lowering the maximum temperature inside the combustion chamber, and thus reducing NOx production to meet stringent emission standards. Conversely, under high-speed or low-load conditions, increasing the flow area of ​​the second flow channel (i.e., increasing asymmetry) reduces pumping losses, optimizes compressor intake efficiency, and further improves engine fuel economy and power output.

[0045] In summary, the synchronous operation of the compressor and turbine, coupled with the dynamic adjustment of asymmetry, enables the asymmetric turbocharger to flexibly adjust the intake pressure and EGR rate over a wide range of engine operating conditions, thereby ensuring high engine performance and fuel efficiency while meeting emission standards.

[0046] In some embodiments of this application, the asymmetric turbocharger further includes a bypass pipe with a vent valve. The vent valve is used to discharge the exhaust gas from the first flow channel and the second flow channel to the turbine to reduce the turbine speed.

[0047] Specifically, a bypass pipe is a conduit connecting the turbine's inlet and outlet, equipped with a bleed valve. When the asymmetric turbocharger is under high boost pressure or the turbine speed is too high, potentially exceeding its safe operating limits, the bleed valve opens to release some exhaust gas, allowing it to bypass the turbine and enter the exhaust system directly or return downstream of the turbine. This reduces the exhaust pressure and flow rate acting on the turbine blades, thereby lowering the turbine speed and preventing overspeeding. Specifically in asymmetric turbochargers, under high-speed conditions, if the flow area of ​​the second flow channel is already adjusted to its maximum but still insufficient to reduce pumping losses, or if the turbine speed abnormally increases due to asymmetry adjustments, the bleed valve will open, allowing some exhaust gas to flow away through the bypass pipe, reducing the turbine's workload. Conversely, under low-speed conditions, the bleed valve typically remains closed to ensure that as much exhaust gas as possible is used to drive the turbine, achieving efficient EGR flow.

[0048] The bypass pipe and wastegate not only help protect the turbocharger from the risk of overspeed damage, but also, under high-speed conditions, timely release of exhaust gas further reduces pumping losses, avoids fuel economy and performance degradation due to excessive exhaust back pressure, and prevents potential safety hazards such as seal failure. Overall, this design improves the operating efficiency and reliability of the asymmetric turbocharger. In conclusion, the bypass pipe and wastegate enable the asymmetric turbocharger to effectively cope with various complex operating conditions that the turbine may encounter while maintaining efficient engine operation.

[0049] This application also provides a method for controlling the asymmetry of any of the above-mentioned asymmetric turbochargers. Figure 3 This is a flowchart illustrating the asymmetry control method according to an embodiment of this application. Figure 3 As shown, the method includes the following steps:

[0050] Step S301: Obtain the engine's operating parameters, including engine speed and fuel injection quantity.

[0051] Step S302: Based on the above operating parameters, determine the target asymmetry corresponding to the above operating parameters through a preset engine operating condition and asymmetry mapping table.

[0052] Step S303: Control the stepper motor to adjust the displacement of the second side of the housing of the second flow channel to adjust the flow area of ​​the second flow channel so that the asymmetry between the first flow channel and the second flow channel reaches the target asymmetry, where the asymmetry is the ratio of the flow area of ​​the second flow channel to the flow area of ​​the first flow channel.

[0053] Specifically, the first step is to collect real-time engine operating parameters, primarily engine speed and fuel injection quantity. These parameters reflect the engine's current load and operating speed, and are crucial for determining how the asymmetric turbocharger operates. Based on the collected operating parameters, a pre-defined engine operating condition-to-asymmetry mapping table is consulted. This is a database established beforehand through experiments and simulations, detailing the ideal asymmetry settings for the engine under different operating conditions. By comparing the current operating parameters with the data in the pre-defined engine operating condition-to-asymmetry mapping table, the target asymmetry that matches the current engine state is determined.

[0054] After obtaining the target asymmetry, the stepper motor is controlled to adjust the displacement of the second side of the housing of the second flow channel, thus changing the flow area of ​​the second flow channel. If the current asymmetry is greater than the target value, the stepper motor is controlled to drive the second side of the housing of the second flow channel to move inward, reducing the flow area of ​​the second flow channel; conversely, if the asymmetry is less than the target value, the second side of the housing of the second flow channel is controlled to move in the opposite direction to increase the flow area of ​​the second flow channel. This adjustment is based on the ratio of the flow area of ​​the second flow channel to the flow area of ​​the first flow channel, i.e., the asymmetry.

[0055] By implementing the above control methods, the asymmetric turbocharger can automatically adapt to different operating conditions throughout the engine's entire operating range, precisely adjusting the asymmetry. Under low engine speed and high load conditions, by reducing the flow area of ​​the second flow channel and decreasing the asymmetry, the pressure before the turbine can be increased, promoting more exhaust gas recirculation and effectively reducing NOx emissions to meet environmental requirements. Under high engine speed and low load conditions, by increasing the flow area of ​​the second flow channel and increasing the asymmetry, pumping losses can be reduced, and exhaust back pressure can be lowered, thereby improving engine fuel economy and overall performance. This avoids the risks of excessive back pressure and turbine overspeed operation that exist in traditional asymmetric turbochargers under certain operating conditions, enhancing the system's safety and reliability. In summary, by combining real-time operating parameters and pre-established mapping relationships, precise control of the asymmetric turbocharger is achieved, ensuring that the engine achieves optimal performance and emission control under different operating conditions.

[0056] In the specific implementation process, before determining the target asymmetry corresponding to the above operating condition parameters through a preset engine operating condition and asymmetry mapping table based on the above operating condition parameters, the above method further includes: performing performance simulations on different engine operating conditions to determine the target EGR rate under the above different engine operating conditions; adjusting the flow area of ​​the above second flow channel based on the above target EGR rate to obtain the target flow area of ​​the above second flow channel under the above different engine operating conditions, and determining the target displacement signal corresponding to the above target flow area of ​​the above second flow channel; determining the asymmetry under the above different engine operating conditions based on the above target flow area of ​​the above second flow channel and the flow area of ​​the above first flow channel; and constructing the preset engine operating condition and asymmetry mapping table based on the above asymmetry under the above different engine operating conditions and the above target displacement signal.

[0057] Specifically, before applying asymmetric turbochargers, performance simulation analysis should be performed on engines under different operating conditions. Advanced computational fluid dynamics (CFD) software or other simulation tools can be used to simulate and predict engine performance at different speeds and fuel injection quantities, especially the impact of EGR rate. The simulation results can determine the target EGR rate that the engine should achieve under specific operating conditions to meet NOx emission limits.

[0058] The target EGR rate was determined, and this was achieved by adjusting the flow area of ​​the second flow channel. A series of tests were conducted on a test bench, recording the impact on the flow area, EGR rate, and overall engine performance by gradually changing the displacement of the second side of the second flow channel housing. This process continued until the optimal second flow channel flow area was found that, under each operating condition, met the target EGR rate requirement while maintaining engine performance and fuel economy. Each change in flow area corresponded to a specific stepper motor displacement signal, i.e., the target displacement signal.

[0059] Based on the target flow area of ​​the second flow channel determined for each operating condition and the target EGR rate obtained from simulation, the corresponding asymmetry is calculated and determined, which is the ratio of the flow area of ​​the second flow channel to the flow area of ​​the first flow channel. This step ensures that each operating point has a clear asymmetry target. Finally, all operating points, corresponding asymmetry, and target displacement signals are integrated to construct a preset engine operating condition and asymmetry mapping table. The preset engine operating condition and asymmetry mapping table serves as the basis for adjusting the asymmetry, ensuring that the engine achieves optimal EGR effect and performance at different times.

[0060] Constructing an accurate mapping table between preset engine operating conditions and asymmetry is fundamental to implementing dynamic asymmetry control. This mapping table integrates theoretical simulations and actual test results, ensuring that the obtained data points accurately reflect the optimal asymmetry settings for the engine under different operating conditions. Through this mapping table, the corresponding target asymmetry can be quickly identified after real-time monitoring of engine operating parameters, allowing for precise adjustment of the flow area of ​​the second flow channel. This satisfies the EGR rate requirement, optimizes engine performance and fuel economy, avoids unnecessary back pressure increases and pumping losses, and improves the stability and safety of the entire system.

[0061] In some embodiments of this application, a stepper motor is controlled to adjust the displacement of the second side of the housing of the second flow channel to adjust the flow area of ​​the second flow channel so that the asymmetry between the first flow channel and the second flow channel reaches the target asymmetry, wherein the asymmetry is the ratio of the flow area of ​​the second flow channel to the flow area of ​​the first flow channel. This includes: matching the target asymmetry and target displacement signal corresponding to the current operating parameters of the engine from the preset engine operating condition and asymmetry mapping table; comparing the target asymmetry with the current asymmetry to determine the displacement adjustment signal of the second side of the housing of the second flow channel; and controlling the stepper motor to adjust the displacement of the second side of the housing of the second flow channel according to the displacement adjustment signal to adjust the flow area of ​​the second flow channel.

[0062] Specifically, the process begins by retrieving the target asymmetry and target displacement signal that match the engine's current speed and cyclic fuel injection quantity from a preset engine operating condition and asymmetry mapping table. Next, the target asymmetry obtained from the preset engine operating condition and asymmetry mapping table is compared with the current asymmetry. If the current asymmetry does not match the target value, the distance the second side of the second flow channel's housing needs to move—the displacement adjustment signal—is calculated based on the difference. This signal instructs the stepper motor to perform the action required, and is a key command to adjust the flow area of ​​the second flow channel, thereby changing the asymmetry. Finally, the displacement adjustment signal is sent to the stepper motor, which drives the second side of the second flow channel's housing to move in a predetermined direction and distance, effectively adjusting the flow area of ​​the second flow channel. When the flow area of ​​the second flow channel changes, its ratio to the flow area of ​​the first flow channel also changes, i.e., the asymmetry is adjusted. This process continues until the flow area of ​​the second flow channel is adjusted to the desired level, and the asymmetry between the first and second flow channels reaches the target value.

[0063] Through the above control methods, the asymmetric turbocharger can track changes in engine operating conditions in real time and respond quickly to adjust the asymmetry of its internal flow channels. It instantly identifies the engine's operating state and rapidly matches the corresponding asymmetry setting, ensuring optimal EGR efficiency and performance at any given time. By comparing the target asymmetry with the current asymmetry in real time, it can issue the most suitable displacement adjustment signal, ensuring that each adjustment is precise and necessary, avoiding energy waste or performance damage caused by over-adjustment. The ability to dynamically adjust asymmetry allows the turbocharger to effectively control emissions while maintaining engine performance, especially in rapidly changing driving environments, flexibly adjusting to meet performance demands under different conditions. In summary, by utilizing a pre-established mapping table between engine operating conditions and asymmetry, combined with real-time operating conditions, the asymmetric turbocharger can automatically adjust to its ideal operating state under various operating conditions.

[0064] Further, comparing the target asymmetry with the current asymmetry to determine the displacement adjustment signal of the second side of the shell of the second flow channel includes: determining whether the flow area of ​​the second flow channel is consistent with the flow area of ​​the second flow channel corresponding to the target asymmetry; if the flow area of ​​the second flow channel is inconsistent with the flow area of ​​the second flow channel corresponding to the target asymmetry, then the displacement signal of the second flow channel corresponding to the target asymmetry is determined as the displacement adjustment signal.

[0065] Specifically, the flow area of ​​the second flow channel is monitored in real time and compared with the flow area corresponding to the target asymmetry. The target asymmetry and its corresponding flow area are obtained from a preset engine operating condition and asymmetry mapping table based on previous performance simulation and bench test data, representing the ideal second flow channel setting under the current operating conditions. If the flow area of ​​the second flow channel is inconsistent with the flow area corresponding to the target asymmetry, it means that it is in a suboptimal state and needs to be adjusted. At this time, the target displacement signal corresponding to the target asymmetry is determined as the displacement adjustment signal. This signal contains the precise displacement command that the stepper motor needs to make to adjust the position of the second side of the second flow channel housing and change the flow area of ​​the second flow channel.

[0066] By monitoring the flow area of ​​the second flow channel in real time and responding immediately when a mismatch with the target setting is detected, the delay or over-adjustment problems that may exist in traditional control methods are avoided. This precise flow area adjustment mechanism helps reduce unnecessary pumping losses, improves fuel economy, and ensures that the exhaust gas recirculation system can effectively reduce NOx emissions under various operating conditions, meeting environmental standards.

[0067] In some embodiments of this application, intelligent learning algorithms, such as machine learning or deep learning, are used to predict the asymmetric requirements of the engine under future operating conditions. By collecting engine operating data in real time, including parameters such as engine speed, fuel injection quantity, intake air temperature, exhaust air temperature, atmospheric pressure, and altitude, and combining historical data with machine learning models, the operating environment the engine will face can be predicted. Based on the prediction results, the flow area of ​​the asymmetric flow channel is adjusted in advance to achieve a dynamic pre-compensation effect, avoiding response lag when operating conditions change rapidly. This intelligent prediction and adaptive adjustment system not only improves control accuracy but also enhances the system's response speed and overall efficiency, especially for frequently changing driving conditions, such as urban traffic congestion and mountain roads, where it has significant advantages.

[0068] To enable those skilled in the art to better understand the technical solution of this application, the implementation process of the asymmetry control method of this application will be described in detail below with reference to specific embodiments.

[0069] This embodiment relates to a specific method for controlling asymmetry. This method is applied to any of the aforementioned asymmetric turbochargers. A schematic diagram of the specific asymmetric turbocharger structure is shown below. Figure 4 As shown, the turbocharger's turbine end includes two flow channels: a large flow channel with a large flow area (first flow channel) and a small flow channel with an adjustable flow area (second flow channel). The asymmetry is matched to different operating conditions by adjusting the flow area of ​​the small flow channel. At low speeds, the stepper motor rotates to reduce the flow area, thereby establishing a pressure difference in the EGR loop connecting the small flow channel and the exhaust pipe, achieving the ideal EGR flow rate. At high speeds, the stepper motor rotates to the right, shifting the right side of the small flow channel to achieve a larger flow area, thereby reducing exhaust back pressure, improving pumping losses, and enhancing fuel economy. Based on the engine's calibration data regarding EGR rate requirements, the EGR rate is achieved by changing the symmetry of the dual flow channels (from 8:2 to 1:1) under different operating conditions.

[0070] In this embodiment, the turbocharger asymmetry can be adjusted as follows: Figure 2 and Figure 5 The structure shown is implemented by splitting the shell of the small flow channel (second flow channel 102). The left side is integrated with the shell of the large flow channel (first flow channel 101). The right side is connected to the stepper motor 20 through a connecting shaft to control the rotation in and out to adjust the flow area. The right side plate moves within the annular groove 103 left in the volute to achieve positioning movement.

[0071] To achieve precise matching between asymmetry and engine operating conditions, this embodiment proposes a cooperative control method, the control logic of which is as follows: Figure 6As shown, its control requires prior calibration of asymmetry and engine operating conditions through experiments to obtain an asymmetry map and the corresponding map relationship between different displacements and asymmetry, which is then written into the ECU as a target value. To meet emission requirements, based on the EGR rate requirements of different operating conditions through performance simulation, bench tests can be used to obtain linear displacement signals of adjustable flow channels that meet EGR rate requirements under different engine operating conditions. According to the displacement of the adjustable flow channel, the corresponding asymmetry map is obtained through the area ratio of geometric relationships. The asymmetry map obtained from the calibration of asymmetry and engine operating conditions, as well as the corresponding map relationship between different displacements and asymmetry, are integrated to obtain a preset engine operating condition and asymmetry mapping relationship table.

[0072] A linear displacement sensor mounted on the housing of the first flow channel monitors the current position of the right-side segment of the small flow channel in real time. The area of ​​the fixed flow channel on the left is constant. Based on the position of the adjustable side plate on the right, the flow area of ​​the right flow channel can be calculated. The maximum value of the right area, i.e., the upper limit of displacement, is consistent with the left area. The ratio of the right area to the left area is the asymmetry, thus calculating the current asymmetry. Based on the stepper motor displacement corresponding to different operating conditions according to the previously calibrated map on the test bench, and according to the real-time engine operating conditions, a signal is output to the stepper motor to achieve precise control of the required asymmetry. The linear displacement sensor can also be mounted on the turbocharger bracket.

[0073] The asymmetric turbocharger and its control method with adjustable asymmetry in this embodiment can meet the engine's EGR flow requirements at low engine speeds, and can also reduce pumping losses at high speeds or low EGR demand points by adjusting the asymmetry, thereby improving engine performance and fuel economy and avoiding reliability risks such as air leakage caused by high back pressure.

[0074] To further optimize the performance of asymmetric turbochargers under extreme environments, some embodiments of this application introduce a temperature and pressure-based dual-flow-channel switching mechanism. During engine operation, when the exhaust temperature or pressure before the turbine is detected to exceed a preset threshold (e.g., indicating excessively high EGR circuit pressure or impending turbine overspeed), the system automatically switches to a backup flow-channel setting. This instantaneously increases the flow area of ​​the second flow-channel or temporarily switches to a symmetric flow-channel mode to alleviate the turbocharger load. This mechanism can rapidly reduce back pressure in emergency situations, preventing turbine overspeed damage, while also avoiding the risk of engine performance degradation and seal failure due to excessive back pressure. By integrating temperature and pressure sensors, along with rapid response logic in emergency situations, the adaptability and reliability of the asymmetric turbocharger are enhanced, ensuring stable engine operation and optimal performance even under extreme conditions.

[0075] This application also provides an asymmetric degree control device. It should be noted that the asymmetric degree control device of this application can be used to execute the asymmetric degree control method provided in this application. This device is used to implement the above embodiments and preferred embodiments; details already described will not be repeated. As used below, the term "module" can refer to a combination of software and / or hardware that implements a predetermined function. Although the device described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0076] The following describes the asymmetry control device provided in the embodiments of this application.

[0077] Figure 7 This is a structural block diagram of an asymmetry control device according to an embodiment of this application. Figure 7 As shown, the device includes an acquisition unit 100, a first determination unit 200, and a control unit 300. The acquisition unit is used to acquire the engine's operating parameters, including engine speed and cyclic fuel injection quantity. The first determination unit is used to determine the target asymmetry corresponding to the operating parameters based on the operating parameters and a preset engine operating condition-asymmetry mapping table. The control unit is used to control a stepper motor to adjust the displacement of the second side of the housing of the second flow channel to adjust the flow area of ​​the second flow channel so that the asymmetry between the first flow channel and the second flow channel reaches the target asymmetry, where the asymmetry is the ratio of the flow area of ​​the second flow channel to the flow area of ​​the first flow channel.

[0078] Through the above embodiments, the asymmetric turbocharger can automatically adapt to different operating conditions throughout the engine's entire operating range, precisely adjusting the asymmetry. Under low engine speed and high load conditions, by reducing the flow area of ​​the second flow channel and decreasing the asymmetry, the pressure before the turbine can be increased, promoting more exhaust gas recirculation and effectively reducing NOx emissions to meet environmental protection requirements. Under high engine speed and low load conditions, by increasing the flow area of ​​the second flow channel and increasing the asymmetry, pumping losses can be reduced, exhaust back pressure can be lowered, thereby improving engine fuel economy and overall performance. This avoids the risks of excessive back pressure and turbine overspeed operation that exist in traditional asymmetric turbochargers under certain operating conditions, enhancing the system's safety and reliability. In summary, by combining real-time operating parameters and pre-established mapping relationships, precise control of the asymmetric turbocharger is achieved, ensuring that the engine achieves optimal performance and emission control under different operating conditions.

[0079] In its specific implementation, the aforementioned device further includes a second determining unit, an adjusting unit, a third determining unit, and a constructing unit. The second determining unit is used to perform performance simulations on different engine operating conditions before determining the target asymmetry corresponding to the operating condition parameters through a preset engine operating condition-asymmetry mapping table based on the operating condition parameters, thereby determining the target EGR rate under the different engine operating conditions. The adjusting unit is used to adjust the flow area of ​​the second flow channel based on the target EGR rate to obtain the target flow area of ​​the second flow channel under the different engine operating conditions, and to determine the target displacement signal corresponding to the target flow area of ​​the second flow channel. The third determining unit is used to determine the asymmetry under the different engine operating conditions based on the target flow area of ​​the second flow channel and the flow area of ​​the first flow channel. The constructing unit is used to construct the preset engine operating condition-asymmetry mapping table based on the asymmetry under the different engine operating conditions and the target displacement signal.

[0080] Constructing an accurate mapping table between preset engine operating conditions and asymmetry is fundamental to implementing dynamic asymmetry control. This mapping table integrates theoretical simulations and actual test results, ensuring that the obtained data points accurately reflect the optimal asymmetry settings for the engine under different operating conditions. Through this mapping table, the corresponding target asymmetry can be quickly identified after real-time monitoring of engine operating parameters, allowing for precise adjustment of the flow area of ​​the second flow channel. This satisfies the EGR rate requirement, optimizes engine performance and fuel economy, avoids unnecessary back pressure increases and pumping losses, and improves the stability and safety of the entire system.

[0081] In some embodiments of this application, the control unit includes a matching module, a comparison module, and a control module. The matching module is used to match the target asymmetry and target displacement signal corresponding to the current operating parameters of the engine from the preset engine operating condition and asymmetry mapping table; the comparison module is used to compare the target asymmetry with the current asymmetry to determine the displacement adjustment signal of the second side of the housing of the second flow channel; the control module is used to control the stepper motor to adjust the displacement of the second side of the housing of the second flow channel according to the displacement adjustment signal to adjust the flow area of ​​the second flow channel.

[0082] Through the above control methods, the asymmetric turbocharger can track changes in engine operating conditions in real time and respond quickly to adjust the asymmetry of its internal flow channels. It instantly identifies the engine's operating state and rapidly matches the corresponding asymmetry setting, ensuring optimal EGR efficiency and performance at any given time. By comparing the target asymmetry with the current asymmetry in real time, it can issue the most suitable displacement adjustment signal, ensuring that each adjustment is precise and necessary, avoiding energy waste or performance damage caused by over-adjustment. The ability to dynamically adjust asymmetry allows the turbocharger to effectively control emissions while maintaining engine performance, especially in rapidly changing driving environments, flexibly adjusting to meet performance demands under different conditions. In summary, by utilizing a pre-established mapping table between engine operating conditions and asymmetry, combined with real-time operating conditions, the asymmetric turbocharger can automatically adjust to its ideal operating state under various operating conditions.

[0083] Furthermore, the comparison module includes a judgment submodule and a determination submodule. The judgment submodule is used to determine whether the flow area of ​​the second flow channel is consistent with the flow area of ​​the second flow channel corresponding to the target asymmetry; the determination submodule is used to determine the displacement signal of the second flow channel corresponding to the target asymmetry as the displacement adjustment signal if the flow area of ​​the second flow channel is inconsistent with the flow area of ​​the second flow channel corresponding to the target asymmetry.

[0084] By monitoring the flow area of ​​the second flow channel in real time and responding immediately when a mismatch with the target setting is detected, the delay or over-adjustment problems that may exist in traditional control methods are avoided. This precise flow area adjustment mechanism helps reduce unnecessary pumping losses, improves fuel economy, and ensures that the exhaust gas recirculation system can effectively reduce NOx emissions under various operating conditions, meeting environmental standards.

[0085] The aforementioned asymmetry control device includes a processor and a memory. The acquisition unit, the first determining unit, the control unit, etc., are all stored as program units in the memory, and the processor executes the program units stored in the memory to achieve the corresponding functions. All of the above modules are located in the same processor; alternatively, the above modules may be located in different processors in any combination.

[0086] The memory may include non-permanent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM, and the memory includes at least one memory chip.

[0087] This invention provides a computer-readable storage medium including a stored program, wherein, when the program is executed, it controls the device containing the computer-readable storage medium to perform the asymmetric degree control method.

[0088] This invention provides a processor for running a program, wherein the program executes the aforementioned asymmetric degree control method during runtime.

[0089] This invention provides an electronic device, including a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, it implements the steps of the aforementioned asymmetric control method. The device described herein can be a server, PC, PAD, mobile phone, etc.

[0090] This application also provides a computer program product that, when executed on a data processing device, is adapted to perform the steps of initializing the control method with the aforementioned asymmetry.

[0091] It is obvious to those skilled in the art that the modules or steps of the present invention described above can be implemented using general-purpose computing devices. They can be centralized on a single computing device or distributed across a network of multiple computing devices. They can be implemented using computer-executable program code, and thus can be stored in a storage device for execution by a computing device. In some cases, the steps shown or described can be performed in a different order than those described herein, or they can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, the present invention is not limited to any particular combination of hardware and software.

[0092] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0093] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0094] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0095] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0096] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0097] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0098] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0099] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0100] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0101] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An asymmetric turbocharger, characterized in that, include: The turbine has a first flow channel and a second flow channel inside its volute. The first flow channel and the second flow channel are connected to the exhaust port of the engine. The flow area of ​​the first flow channel is fixed, and the flow area of ​​the second flow channel can be adjusted within a preset range. The housing of the second flow channel is a split type, and the first side of the housing of the second flow channel is an integral structure with the housing of the first flow channel. A stepper motor is connected to the second side of the housing of the second flow channel via a connecting shaft, and is used to control the displacement of the second side of the housing of the second flow channel to adjust the flow area of ​​the second flow channel; A controller, which is communicatively connected to the engine and the stepper motor, is used to receive the engine's operating parameters and, based on the operating parameters and a preset engine operating condition and asymmetry mapping table, control the stepper motor to adjust the flow area of ​​the second flow channel, so as to control the asymmetry between the first flow channel and the second flow channel to reach a target asymmetry, wherein the asymmetry is the ratio of the flow area of ​​the second flow channel to the flow area of ​​the first flow channel.

2. The asymmetric turbocharger according to claim 1, characterized in that, The asymmetric turbocharger also includes: A displacement sensor is disposed on the housing of the first flow channel to detect displacement information on the second side of the housing of the second flow channel and transmit the displacement information to the controller.

3. The asymmetric turbocharger according to claim 1, characterized in that, The turbine casing includes: An annular groove is provided on the second side of the housing of the second flow channel, and the annular groove is provided with a guiding mechanism for controlling the second side of the housing of the second flow channel to move along the first direction of the annular groove, the first direction of the annular groove being perpendicular to the axial center line of the second flow channel.

4. The asymmetric turbocharger according to claim 1, characterized in that, The asymmetric turbocharger also includes: A compressor, which is connected to the turbine.

5. The asymmetric turbocharger according to claim 1, characterized in that, The asymmetric turbocharger also includes: A bypass pipe is provided, and a vent valve is provided on the bypass pipe. The vent valve is used to discharge the exhaust gas from the first flow channel and the second flow channel to the turbine to reduce the turbine speed.

6. A method for controlling the asymmetry of an asymmetric turbocharger applied to any one of claims 1 to 5, characterized in that, include: The engine operating parameters are obtained, including engine speed and fuel injection quantity per cycle. Based on the operating parameters, the target asymmetry corresponding to the operating parameters is determined by a preset engine operating condition and asymmetry mapping table. The stepper motor is controlled to adjust the displacement of the second side of the housing of the second flow channel to adjust the flow area of ​​the second flow channel so that the asymmetry between the first flow channel and the second flow channel reaches the target asymmetry, wherein the asymmetry is the ratio of the flow area of ​​the second flow channel to the flow area of ​​the first flow channel.

7. The method according to claim 6, characterized in that, Before determining the target asymmetry corresponding to the operating parameters based on the operating parameters using a preset engine operating condition and asymmetry mapping table, the method further includes: Performance simulations were performed under different engine operating conditions to determine the target EGR rate under those different engine operating conditions; The flow area of ​​the second flow channel is adjusted based on the target EGR rate to obtain the target flow area of ​​the second flow channel under different engine operating conditions, and the target displacement signal corresponding to the target flow area of ​​the second flow channel is determined. The asymmetry under different engine operating conditions is determined based on the target flow area of ​​the second flow channel and the flow area of ​​the first flow channel. Based on the asymmetry under different engine operating conditions and the target displacement signal, a mapping table between the preset engine operating conditions and asymmetry is constructed.

8. The method according to claim 6, characterized in that, The stepper motor is controlled to adjust the displacement of the second side of the housing of the second flow channel to adjust the flow area of ​​the second flow channel so that the asymmetry between the first flow channel and the second flow channel reaches the target asymmetry, wherein the asymmetry is the ratio of the flow area of ​​the second flow channel to the flow area of ​​the first flow channel, including: Match the target asymmetry and target displacement signals corresponding to the current operating parameters of the engine from the preset engine operating condition and asymmetry mapping table; The target asymmetry is compared with the current asymmetry to determine the displacement adjustment signal of the second side of the shell of the second flow channel; The stepper motor is controlled to adjust the displacement of the second side of the housing of the second flow channel according to the displacement adjustment signal, so as to adjust the flow area of ​​the second flow channel.

9. The method according to claim 8, characterized in that, Comparing the target asymmetry with the current asymmetry to determine the displacement adjustment signal of the second side of the housing of the second flow channel includes: Determine whether the flow area of ​​the second flow channel is consistent with the flow area of ​​the second flow channel corresponding to the target asymmetry; If the flow area of ​​the second flow channel is inconsistent with the flow area of ​​the second flow channel corresponding to the target asymmetry, then the displacement signal of the second flow channel corresponding to the target asymmetry is determined as the displacement adjustment signal.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored program, wherein, when the program is executed, it controls the device containing the computer-readable storage medium to perform the asymmetry control method according to any one of claims 6 to 9.

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