Engine control method, system and equipment, medium and vehicle

Abstract

The invention discloses an engine control method, system and device, a medium and a vehicle. In the shutdown process of an engine, the working condition of the engine, the rotating speed of the engine and the running state of the vehicle are obtained; and controlling the engine to stop at a preset position based on the engine working condition, the engine rotating speed and the automobile running state. The stop position of the engine is controlled according to different engine working conditions, a piston of a certain cylinder is stopped in the air inlet compression process, the instant friction torque of the engine can be small when the engine is started again, and therefore the impact feeling in the engine starting process is reduced, and the driving comfort is improved.

Description

Technical Field

[0001] The present application relates to the field of automobile technology, and in particular to an engine control method, system, device, medium and vehicle. Background Art

[0002] In hybrid vehicles, the vehicle system decides whether to shut down or start the engine according to the vehicle and road conditions. This process often occurs when the vehicle is running, so it starts more frequently than conventional vehicle engines. The engine of a hybrid vehicle often requires an electric motor to drag the engine to a higher speed in order to quickly enter the working state. At this time, it is necessary to overcome the static friction of the engine's moving parts and the compression reaction force of the piston on the air in the cylinder. Since the static friction is greater than the dynamic friction, and when the piston is dragged and is just near the end of the compression stroke, the reaction force of the compressed gas is large, and the blocking force will have a significant impact on the vehicle's transmission system, causing a load impact on the entire vehicle, reducing driving comfort and system reliability.

[0003] When a conventional automobile engine is shut down, the system first stops injecting fuel and igniting. At this time, the moving mechanism components are no longer driven by the fuel and enter free operation. Due to their own inertia, they will still rotate for a certain distance until the friction and pump gas-compression reaction force consume the kinetic energy of the system, causing the moving mechanism components to stop rotating. Since the position of the piston stop is not controlled during the process, the position of the piston after the stop has a certain randomness, and is more likely to be distributed before the compression top dead center. The main reason is that the piston is forced to stop by the reaction force of the gas compression in the cylinder. In this case, there is a certain amount of gas in the cylinder. When the motor drags the engine, the piston compresses the air to generate a resistance torque, which will cause the engine to have a large instantaneous friction torque, causing a large load on the starting system.

[0004] Therefore, how to reduce the resistance during engine starting is a technical problem that technicians in this field urgently need to solve. Summary of the invention

[0005] Based on the above problems, the present application provides an engine control method, system, device, medium and vehicle, aiming to.

[0006] To solve the above problems, the technical solutions provided in the embodiments of the present application are as follows:

[0007] A first aspect of the present application provides an engine control method, comprising:

[0008] During the engine shutdown process, obtain the engine operating condition, engine speed and vehicle running status;

[0009] Based on the engine operating condition, engine speed and vehicle running state, the engine is controlled to stop at a preset position.

[0010] Optionally, controlling the engine to stop at a preset position based on the engine operating condition, engine speed and vehicle running state includes:

[0011] When the engine operating condition is one of the engine generating conditions or the engine driving the motor to jointly drive the entire vehicle, the engine speed is reduced to zero, and the vehicle is in a driving state, the generator is used as an electric motor to drive the engine, so that the first cylinder of the engine stops at a preset angle before the compression top dead center.

[0012] Optionally, controlling the engine to stop at a preset position based on the engine operating condition, engine speed and vehicle running state includes:

[0013] When the engine operating condition is any one of an engine power generation condition, an engine direct drive condition, or an engine driving a motor to drive the vehicle together, the engine speed is reduced to zero, and the vehicle is in a stopped state, the engine is driven by the driving motor to stop the first cylinder of the engine to a preset angle interval before the compression top dead center;

[0014] The generator is used as a motor to drive the engine, so that the first cylinder of the engine stops at a preset angle before the compression top dead center.

[0015] Optionally, the engine is connected to the generator, and the engine is used to drive the generator to generate electricity when the engine speed drops to zero during the shutdown process of the engine.

[0016] Optionally, the generator is connected to the front end output shaft of the engine via gears, or the engine is arranged on the front end output shaft of the engine.

[0017] In a second aspect, an embodiment of the present application provides a system, including:

[0018] An acquisition unit, used to acquire engine operating conditions, engine speed and vehicle operating status during engine shutdown;

[0019] The control unit is used to control the engine to stop at a preset position based on the engine operating condition, engine speed and vehicle running state.

[0020] Optionally, the control unit is specifically used to, when the engine operating condition is one of the engine generating conditions or the engine driving the motor to jointly drive the entire vehicle, the engine speed is reduced to zero, and the vehicle is in a driving state, use the generator as an electric motor to drive the engine, so that the first cylinder of the engine stops at a preset angle before the top dead center of compression.

[0021] In a third aspect, an embodiment of the present application provides a device, comprising a memory and a processor, wherein the memory is used to store instructions or codes, and the processor is used to execute the instructions or codes so that the device executes the engine control method described in any one of the first aspects above.

[0022] In a fourth aspect, an embodiment of the present application provides a computer storage medium, in which codes are stored. When the codes are executed, a device executing the codes implements the engine control method described in any one of the first aspects above.

[0023] In a fifth aspect, an embodiment of the present application provides a vehicle, wherein the vehicle comprises a central electronic control module, and the central electronic control module is used to execute the engine control method described in any one of the first aspects.

[0024] Compared with the prior art, this application has the following beneficial effects:

[0025] The engine control method, system, device, medium and vehicle provided in the present application obtain the engine working condition, engine speed and vehicle running state during the engine shutdown process; based on the engine working condition, engine speed and vehicle running state, the engine is controlled to stop at a preset position. That is, the engine shutdown position is controlled according to different engine working conditions, so that a certain cylinder piston stops during the intake compression process, so that the instantaneous friction torque of the engine is small when the engine is restarted, thereby reducing the impact during the engine startup process and improving driving comfort. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in this embodiment or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 A schematic diagram of an engine assembly provided in an embodiment of the present application;

[0028] Figure 2 A flow chart of an engine control method provided in an embodiment of the present application;

[0029] Figure 3 A structural diagram of an engine control system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0030] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0031] As mentioned above, in the prior art, when a conventional automobile engine is shut down, the system first stops injecting fuel and igniting. At this time, the moving mechanism components are no longer driven by the fuel and enter free operation. Due to their own inertia, they will still rotate a certain distance until the friction and pump gas-compression reaction force consume the kinetic energy of the system, causing the moving mechanism components to stop rotating. Since the position of the piston stop is not controlled during the process, the position of the piston after the stop has a certain randomness, and is more likely to be distributed before the compression top dead center. The main reason is that the piston is forced to stop by the reaction force of the gas compression in the cylinder. In this case, there is a certain amount of gas in the cylinder. When the motor drags the engine, the piston compresses the air to generate a resistance torque, which will cause the engine to have a large instantaneous friction torque, causing a large load on the starting system.

[0032] In view of this, by controlling the engine's stop position through the generator and the drive motor, the instantaneous friction torque of the engine can be reduced when the engine is started again, thereby reducing the impact during the engine start-up process, optimizing the vehicle's NVH (Noise, Vibration, Harshness) and improving driving comfort.

[0033] Figure 1The schematic diagram of the combined device of the engine provided by the embodiment of the present application, the embodiment of the present application discloses an engine 1, an engine output shaft 2, a first gear 3, a second gear 4, a generator 5, a clutch 6, a third gear 7, a fourth gear 8, a fifth gear 9, a drive motor 10, a sixth gear 11, and a differential 12, one end of the engine output shaft 2 is arranged in the engine 1, the other end of the engine output shaft 2 is connected to one end of the clutch 6, the first gear 3 is connected to the middle part of the engine output shaft 2, the second gear 4 is meshed with the first gear 3, the connecting shaft of the generator 5 is connected to the second gear 4, the connecting shaft of the third gear 7 is connected to the other end of the clutch 6, the fourth gear 8 is respectively meshed with the third gear 7 and the fifth gear 9, the connecting shaft of the drive motor 10 is connected to the fifth gear 9, the fourth gear 8 and the sixth gear 11 are connected through the connecting shaft, and the differential 12 is meshed with the sixth gear 11. In the present invention, the generator 5 can also be directly connected to the engine output shaft 2, that is, it becomes an ISG generator (Integrated Starter Generator, starting / generating integrated motor).

[0034] The following is an example of an engine control method provided by the present application. Figure 1 , Figure 1 This is a flow chart of an engine control method provided in an embodiment of the present application. The control method provided in this embodiment can be executed by an engine control system, including:

[0035] S101. During the engine shutdown process, obtain the engine operating condition, engine speed and vehicle running status.

[0036] The engine operating conditions may include engine power generation conditions, engine direct drive conditions, and the engine and the drive motor driving the vehicle together. The vehicle running state includes a stop state and a driving state.

[0037] S102: Based on the engine operating condition, engine speed and vehicle running state, control the engine to stop at a preset position.

[0038] During the shutdown process of the engine, the shutdown position of the engine is controlled by the generator and the drive motor according to different shutdown conditions, so that the piston of a certain cylinder stops during the intake compression process and stops at a preset position.

[0039] In a possible implementation, the engine is connected to the generator, and the engine is used to drive the generator to generate electricity when the engine speed decreases to zero during the shutdown process of the engine.

[0040] In a possible implementation, the generator is connected to the front output shaft of the engine via a gear, or the engine is arranged on the front output shaft of the engine.

[0041] In a possible implementation, controlling the engine to stop at a preset position based on the engine operating condition, engine speed, and vehicle running state includes:

[0042] When the engine operating condition is one of the engine generating conditions or the engine driving the motor to jointly drive the entire vehicle, the engine speed is reduced to zero, and the vehicle is in a driving state, the generator is used as an electric motor to drive the engine, so that the first cylinder of the engine stops at a preset angle before the compression top dead center.

[0043] During the implementation of the present invention, when the engine 1 is only running in the power generation condition, the engine 1 is only used to drive the generator 5 to work alone; at this time, the clutch 6 is separated, and the whole vehicle is in a state of being driven by the drive motor 10 alone. When charging is completed, or the whole vehicle needs to stop, the engine 1 needs to be shut down. Under this condition, during the shutdown process of the engine 1, when the speed of the engine 1 gradually decreases to zero, the engine 1 is still used to drive the generator 5 to generate electricity; when the speed of the engine 1 decreases to zero, the controller reverses the generator 5 to become an electric motor, driving the first cylinder piston of the engine 1 to stop at a preset angle before the compression top dead center. In actual application scenarios, the preset angle can be set to 90 degrees, even if its first cylinder stops precisely 90 degrees before the compression top dead center.

[0044] When the engine 1 is running only in direct drive mode, the generator 5 and the drive motor 10 are not working, the clutch 6 is closed, and the whole vehicle is in a state of being driven solely by the engine 1. When the drive motor 10 needs to intervene to drive the whole vehicle alone, or the whole vehicle needs to stop, the engine 1 needs to be shut down. Under this condition, during the shutdown process of the engine 1, when the speed of the engine 1 gradually decreases to zero, the engine 1 is used to drive the generator 5 to generate electricity; when the speed of the engine 1 decreases to zero, the controller controls the drive motor 10 to drive the first cylinder piston of the engine 1 to stop at a preset angle before its compression top dead center. In actual application scenarios, the preset angle can be set to 90 degrees, that is, its first cylinder stops precisely 90 degrees before the compression top dead center.

[0045] When the engine 1 and the drive motor 10 drive the whole vehicle together, the clutch 6 is closed, the engine 1 and the drive motor 10 work in parallel, and the generator 5 is in a non-working state. When the drive motor 10 is required to drive the whole vehicle alone, or the whole vehicle needs to stop, the engine 1 needs to be shut down. Under this working condition, during the shutdown process of the engine 1, when the speed of the engine 1 gradually decreases to zero, the engine 1 is still used to drive the generator 5 to generate electricity; when the speed of the engine 1 decreases to zero, the controller reverses the generator 5 to become an electric motor, driving the first cylinder piston of the engine 1 to stop at a preset angle before its compression top dead center. In actual application scenarios, the preset angle can be set to 90 degrees, even if its first cylinder stops precisely 90 degrees before the compression top dead center.

[0046] In this embodiment, when the engine 1 is stopped, the pistons of the first cylinder all stop at a preset angle before the compression top dead center, and at this time, the pistons in the four cylinders are all in the middle of their strokes. For hybrid vehicles, during the operation of the entire vehicle, the engine 1 is generally not started immediately after it is stopped. When the piston of the first cylinder stops at a preset angle before the compression top dead center, there is a certain amount of compressed gas above the piston of the first cylinder. As time goes by, this part of the compressed gas will leak out through the valve and piston ring of the first cylinder, and the pressure in the cavity above the piston will be basically the same as the atmospheric environment. When the engine 1 is started again, the stroke of the piston of the first cylinder during the upward movement is only half of the original stroke. At this time, the resistance of the final compression pressure to the piston will also become smaller, thereby reducing the impact during the engine startup process, optimizing the vehicle NVH, and improving driving comfort.

[0047] In a possible implementation, controlling the engine to stop at a preset position based on the engine operating condition, engine speed, and vehicle running state includes:

[0048] When the engine operating condition is any one of the engine power generation condition, the engine direct drive condition or the engine driving the motor to jointly drive the whole vehicle, the engine speed is reduced to zero and the vehicle is in a stopped state, the engine is driven by the driving motor to stop the first cylinder of the engine to a preset angle interval before the compression top dead center; the generator is used as an electric motor to drive the engine to stop the first cylinder of the engine to a preset angle before the compression top dead center.

[0049] When the engine is running only in the power generation condition, during the shutdown process of the engine, when the engine speed gradually decreases to zero, the engine is still used to drive the generator to generate electricity; when the engine speed decreases to zero, if the car has stopped driving at this time, the engine is driven by the drive motor to stop the first cylinder to a preset angle interval before the compression top dead center, and then the generator is converted into an electric motor by the controller to drive the engine to accurately stop the first cylinder to the preset angle before the compression top dead center. In actual application scenarios, the preset angle can be set to 90 degrees, and the preset angle interval can be set to 70 degrees to 110 degrees, that is, the engine is driven by the drive motor to stop the first cylinder to 70 degrees to 110 degrees before the compression top dead center, and then the generator is converted into an electric motor by the controller to drive the engine to accurately stop the first cylinder to 90 degrees before the compression top dead center.

[0050] When the engine is running only in direct drive conditions, during the engine shutdown process, when the engine speed gradually decreases to zero, the engine is used to drive the generator to generate electricity; when the engine speed decreases to zero, if the car has stopped driving at this time, the drive motor drives the engine to stop the first cylinder to a preset angle interval before the compression top dead center, and then the controller converts the generator into an electric motor to drive the engine to accurately stop the first cylinder to the preset angle before the compression top dead center.

[0051] When the engine and the drive motor drive the whole vehicle together, during the engine shutdown process, when the engine speed gradually decreases to zero, the engine is still used to drive the generator to generate electricity; when the engine speed decreases to zero, if the car has stopped driving at this time, the drive motor drives the engine to stop the first cylinder to a preset angle interval before the compression top dead center, and then the controller converts the generator into an electric motor to drive the engine to accurately stop the first cylinder to the preset angle before the compression top dead center.

[0052] For a four-cylinder engine with a firing order of 1 cylinder, 3 cylinder, 4 cylinder, and 2 cylinder, if the first cylinder stops at the compression top dead center when the engine 1 is shut down, the third cylinder is at the intake bottom dead center. When the engine 1 is restarted, the piston stroke of the third cylinder remains unchanged, and the third cylinder will still generate a large compression pressure; if the first cylinder stops at the intake bottom dead center when the engine 1 is shut down, the first cylinder will generate a large compression pressure when the engine 1 is restarted. Therefore, it is more reasonable for the pistons of each cylinder of the engine 1 to stop at the middle position when the engine 1 is shut down. In the actual operation process, the control accuracy can be appropriately lowered, and the first cylinder can be stopped at a preset angle interval before its compression top dead center, such as 70 to 110 degrees before the compression top dead center.

[0053] In multiple working conditions of the present invention, the driving motor 10 drives the engine 1 to stop its first cylinder to a preset angle interval before the compression top dead center, and then the controller changes the generator 5 into an electric motor to drive the engine 1 to accurately stop its first cylinder to a preset angle before the compression top dead center, such as 90 degrees before the compression top dead center. This is because the generator 5 is directly connected to the engine 1 through the second gear 4, the first gear 3, and the engine output shaft 2, and the generator 5 and the engine 1 are directly connected by gears; and between the driving motor 10 and the engine 1, in addition to the gear connection, there is also a clutch 6. Because many clutches 6 are hydraulic, if the driving motor 10 drives the engine 1 to accurately stop its first cylinder to a preset angle before the compression top dead center, such as 90 degrees before the compression top dead center, the control accuracy is inferior to that of the generator 5. The clutch 6 can control the transmission of torque well, but it is still slightly lacking in precise shutdown control.

[0054] Compared with the prior art, the embodiment provided in the present application controls the stop position of the engine through a generator or a drive motor, so that the instantaneous friction torque of the engine can be smaller when the engine is started again, thereby reducing the impact during the engine starting process, optimizing the vehicle NVH, and improving driving comfort.

[0055] The above are some specific implementations of the engine control method provided in the embodiment of the present application. Based on this, the present application also provides a corresponding system for engine control. The system provided in the embodiment of the present application will be introduced from the perspective of functional modularization. Figure 2 A structural diagram of an engine control system provided in an embodiment of the present application.

[0056] The present application also provides an engine control system, including:

[0057] The acquisition unit 110 is used to acquire the engine operating condition, engine speed and vehicle running state during the engine shutdown process;

[0058] The control unit 111 is used to control the engine to stop at a preset position based on the engine operating condition, engine speed and vehicle running state.

[0059] Optionally, the control unit is specifically used to, when the engine operating condition is one of the engine generating conditions or the engine driving the motor to jointly drive the entire vehicle, the engine speed is reduced to zero, and the vehicle is in a driving state, use the generator as an electric motor to drive the engine, so that the first cylinder of the engine stops at a preset angle before the top dead center of compression.

[0060] Optionally, the control unit is specifically used to drive the engine by driving the motor so that the first cylinder of the engine stops at a preset angle interval before the top dead center of compression when the engine operating condition is any one of the engine generating condition, the engine direct drive condition or the engine driving the motor to jointly drive the whole vehicle, and the engine speed is reduced to zero and the vehicle is in a stopped state; the generator is used as an electric motor to drive the engine so that the first cylinder of the engine stops at a preset angle before the top dead center of compression.

[0061] Optionally, the engine is connected to the generator, and the engine is used to drive the generator to generate electricity when the engine speed drops to zero during the shutdown process of the engine.

[0062] Optionally, the generator is connected to the front end output shaft of the engine via gears, or the engine is arranged on the front end output shaft of the engine.

[0063] An embodiment of the present application provides a device, which includes a memory and a processor, wherein the memory is used to store instructions or codes, and the processor is used to execute the instructions or codes so that the device executes any of the aforementioned engine control methods.

[0064] An embodiment of the present application provides a computer storage medium, in which codes are stored. When the codes are executed, a device executing the codes implements any of the aforementioned engine control methods.

[0065] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments can be referred to each other. For the system or device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part description.

[0066] It should be understood that in the present application, "at least one (item)" means one or more, and "plurality" means two or more. "And / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally indicates that the objects associated before and after are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, c can be single or multiple.

[0067] It should also be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0068] The steps of the method or algorithm described in conjunction with the embodiments disclosed herein may be implemented directly using hardware, a software module executed by a processor, or a combination of the two. The software module may be placed in a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0069] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An engine control method, characterized in that: include: During the engine shutdown process, obtain the engine operating condition, engine speed and vehicle running status; Based on the engine operating condition, engine speed and vehicle running state, the engine is controlled to stop at a preset position.

2. The method according to claim 1, characterized in that: The controlling the engine to stop at a preset position based on the engine operating condition, the engine speed and the vehicle running state comprises: When the engine operating condition is one of the engine generating conditions or the engine driving the motor to jointly drive the entire vehicle, the engine speed is reduced to zero, and the vehicle is in a driving state, the generator is used as an electric motor to drive the engine, so that the first cylinder of the engine stops at a preset angle before the compression top dead center.

3. The method according to claim 1, characterized in that The controlling the engine to stop at a preset position based on the engine operating condition, the engine speed and the vehicle running state comprises: When the engine operating condition is any one of an engine power generation condition, an engine direct drive condition, or an engine driving a motor to drive the vehicle together, the engine speed is reduced to zero, and the vehicle is in a stopped state, the engine is driven by the driving motor to stop the first cylinder of the engine to a preset angle interval before the compression top dead center; The generator is used as a motor to drive the engine, so that the first cylinder of the engine stops at a preset angle before the compression top dead center.

4. The method according to any one of claims 1 to 3, characterized in that The engine is connected to the generator, and the engine is used to drive the generator to generate electricity when the engine speed decreases to zero during the shutdown process of the engine.

5. The method according to claim 4, characterized in that The generator is connected to the front output shaft of the engine through a gear, or the generator is arranged on the front output shaft of the engine.

6. An engine control system, characterized in that: include: An acquisition unit, used to acquire engine operating conditions, engine speed and vehicle operating status during engine shutdown; The control unit is used to control the engine to stop at a preset position based on the engine operating condition, engine speed and vehicle running state.

7. The system according to claim 6, characterized in that The control unit is specifically used to, when the engine operating condition is one of the engine generating operating condition or the engine driving the motor to jointly drive the whole vehicle, the engine speed is reduced to zero, and the vehicle is in a driving state, use the generator as an electric motor to drive the engine, so that the first cylinder of the engine stops at a preset angle before the compression top dead center.

8. An electronic device, characterized in that: include: Processor, memory, system bus; The processor and the memory are connected via the system bus; The memory is used to store one or more programs, wherein the one or more programs include instructions, and when the instructions are executed by the processor, the processor executes the engine control method according to any one of claims 1 to 5.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores codes, and when the codes are executed, a device executing the codes implements the engine control method according to any one of claims 1 to 5.

10. A vehicle, characterized in that: The vehicle includes a central electronic control module, and the central electronic control module is used to execute the engine control method described in any one of claims 1-5.

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