Clutch control methods, shifting methods, vehicles, media, and computer program products

Abstract

This invention discloses a clutch control method, a shifting method, a vehicle, a medium, and a computer program product. The clutch control method includes: responding to an engagement command, controlling a first motor to output a starting torque so that the first end face teeth and the second end face teeth have a target speed difference; controlling a jaw clutch to perform an engagement action; acquiring the output speed of the first motor; if the output speed is not zero, then re-controlling the first motor to output the starting torque and controlling the jaw clutch to perform the engagement action until the output speed is zero, and the jaw clutch engagement is completed. The clutch control method of this invention, by creating a target speed difference between the first end face teeth and the second end face teeth, allows the first end face teeth and the second end face teeth to stagger their tooth tip states during engagement to smoothly slide into the meshing position, solving the technical problem in the prior art where the jaw clutch cannot reliably engage in the parking state because both ends of the clutch have no speed.

Description

Technical Field

[0001] This invention relates to the field of clutch control technology, and in particular to a clutch control method, a shifting method, a vehicle, a medium, and a computer program product. Background Technology

[0002] In the powertrain systems of hybrid vehicles, dog clutches (also known as dog clutches) are widely used for power on / off control between the motor and the wheels due to their high transmission efficiency and lack of drag torque.

[0003] Currently, engagement control of jaw clutches typically relies on monitoring and controlling the speed difference between the two ends of the clutch. For example, prior art CN115991185B discloses an electromagnetic clutch control method that uses a closed-loop monitoring system based on the speed difference between the two ends of the electromagnetic clutch to monitor the clutch state. However, this type of method is suitable for dynamic engagement scenarios where a speed difference already exists between the two ends of the clutch during vehicle operation. When the vehicle is parked, the speed of the end of the jaw clutch connected to the wheel is zero, and the speed of the end connected to the motor is also zero because the motor is not running. There is no speed difference between the two ends of the clutch. In this case, existing dynamic control methods that rely on speed difference fail, and reliable clutch engagement cannot be achieved. Furthermore, since the engagement teeth of the jaw clutch have flat surfaces, direct engagement under static conditions where neither end rotates can easily lead to a "tooth-on-tooth" phenomenon, resulting in engagement failure.

[0004] Therefore, the existing technology lacks a control method that can reliably control the engagement of a dog clutch when there is no initial speed at either end of the dog clutch. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a clutch control method, a shifting method, a vehicle, a medium, and a computer program product to solve the technical problem that the prior art lacks a control method that can reliably control the engagement of a jaw clutch when there is no initial speed at both ends of the jaw clutch.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: In a first aspect, the present invention provides a clutch control method applied to a vehicle powertrain system, the vehicle powertrain system including a first motor, a jaw clutch, and a first differential, the jaw clutch having a first end face tooth and a second end face tooth for engagement, the first end face tooth being drive-connected to the first motor, the second end face tooth being drive-connected to the first differential, and the first differential being in a stationary state; the clutch control method includes the following steps: In response to the engagement command, the first motor is controlled to output starting torque so that the first end face tooth and the second end face tooth have a target speed difference; Control the jaw clutch to perform the engagement action; The output speed of the first motor is obtained. If the output speed is not zero, the first motor is controlled to output the starting torque again, and the jaw clutch is controlled to perform the engagement action until the output speed is zero, and the jaw clutch engagement is completed.

[0007] In some embodiments, the starting torque includes a first pulse torque and a holding torque; controlling the first motor to output the starting torque so that the first end face tooth and the second end face tooth have a target speed difference includes: The first motor is controlled to output the first pulse torque so that the first end face tooth and the second end face tooth generate the target speed difference; The first motor is controlled to continuously output the holding torque so that the speed difference between the first end face tooth and the second end face tooth is maintained at the target speed difference; the holding torque is less than the first pulse torque.

[0008] In some embodiments, the holding torque is determined by the following steps: Obtain the real-time frictional resistance from the first motor to the first end face teeth; Calculate the base torque required to overcome the real-time frictional resistance, and use the base torque as the holding torque.

[0009] In some embodiments, controlling the first motor to continuously output the holding torque so that the speed difference between the first end face tooth and the second end face tooth is maintained at the target speed difference includes: Control the first motor to continuously output the holding torque, and determine whether the speed difference between the first end face tooth and the second end face tooth is the target speed difference; If not, the first motor is controlled to output the first pulse torque and the holding torque again, and the speed difference between the first end face tooth and the second end face tooth is re-determined to be the target speed difference until the speed difference between the first end face tooth and the second end face tooth is maintained at the target speed difference.

[0010] In some embodiments, the output speed of the first motor is obtained; if the output speed is not zero, the first motor is re-controlled to output the starting torque, and the jaw clutch is controlled to perform an engagement action until the output speed is zero, at which point the jaw clutch engagement is complete. This includes: The first output speed of the first motor is obtained. If the first output speed is not zero, the first motor is controlled to output the starting torque and the jaw clutch is controlled to perform an engagement action until the first output speed is zero. When the first output speed is zero, the first motor is controlled to output a second pulse torque and the second output speed of the first motor is obtained. If the second output speed is not zero, the first motor is controlled to output the starting torque again and the jaw clutch is controlled to perform the engagement action until the second output speed is zero and the jaw clutch engagement is completed.

[0011] In some embodiments, there is shaft frictional resistance between the first motor and the teeth on the first end face; the second pulse torque is greater than or equal to the base torque, which is the torque required to overcome the shaft frictional resistance. Secondly, the present invention provides a gear shifting method in which, in parking mode, in response to a pure electric mode switching command, the dog clutch is engaged by means of the clutch control method described in the first aspect.

[0012] Thirdly, the present invention provides a gear shifting method applied to a vehicle powertrain system, the vehicle powertrain system including a first motor, a second motor, a jaw clutch, a first differential, and a second differential, the second motor being drive-connected to the second differential, and both the first differential and the second differential being in a stationary state; the vehicle gear shifting method includes: In response to the pure electric four-wheel drive mode switching command, the engagement of the jaw clutch is controlled by the clutch control method described in the first aspect.

[0013] Fourthly, the present invention provides a vehicle comprising: a controller, the controller comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the computer instructions to implement the clutch control method of the first aspect and / or the gear shifting method of the second and third aspects.

[0014] Fifthly, the present invention provides a computer storage medium storing program code, which is loaded and executed by a processor to implement the clutch control method described in the first aspect and / or the gear shifting method described in the second and third aspects.

[0015] In a sixth aspect, the present invention provides a computer program product comprising computer instructions stored in a computer-readable storage medium and adapted to be read and executed by a processor to cause a computer device having the processor to perform the clutch control method as described in the first aspect and / or the shifting method as described in the second and third aspects.

[0016] The clutch control method of the present invention controls the output of the starting torque of the first motor in response to the engagement command. Under the condition that the first differential is stationary and the speed of the second end face tooth is zero, the first end face tooth is actively driven to rotate, thereby creating a target speed difference between the first end face tooth and the second end face tooth. The existence of the target speed difference allows the first end face tooth and the second end face tooth to be staggered during the engagement process, so that the first end face tooth and the second end face tooth can smoothly slide into the meshing position. This solves the technical problem of the prior art that the dog clutch cannot be reliably engaged in the parking state because there is no speed at both ends of the clutch.

[0017] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other objects, features and advantages of the present invention more obvious and understandable, preferred embodiments are described in detail below. Attached Figure Description

[0018] Figure 1 This is a flowchart of a clutch control method in an exemplary embodiment of this application; Figure 2 This is a first sub-flowchart of a clutch control method in an exemplary embodiment of this application; Figure 3 This is a second sub-flowchart of the clutch control method in an exemplary embodiment of this application; Figure 4 This is a third sub-flowchart of the clutch control method in an exemplary embodiment of this application; Figure 5 This is a fourth sub-flowchart of the clutch control method in an exemplary embodiment of this application; Figure 6 This is a schematic diagram of the composition of a jaw clutch control device in an exemplary embodiment of this application; Figure 7 This is a schematic diagram of the structure of an electronic device in an exemplary embodiment of this application. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0023] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0024] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0025] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. The illustrative expressions of the above terms in this specification should not be construed as necessarily referring to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0026] In the powertrain systems of hybrid vehicles, dog clutches (also known as dog clutches) are widely used for power on / off control between the motor and the wheels due to their high transmission efficiency and lack of drag torque.

[0027] Currently, engagement control of jaw clutches typically relies on monitoring and controlling the speed difference between the two ends of the clutch. For example, prior art CN115991185B discloses an electromagnetic clutch control method that uses a closed-loop monitoring system based on the speed difference between the two ends of the electromagnetic clutch to monitor the clutch state. However, this type of method is suitable for dynamic engagement scenarios where a speed difference already exists between the two ends of the clutch during vehicle operation. When the vehicle is parked, the speed of the end of the jaw clutch connected to the wheel is zero, and the speed of the end connected to the motor is also zero because the motor is not running. There is no speed difference between the two ends of the clutch. In this case, existing dynamic control methods that rely on speed difference fail, and reliable clutch engagement cannot be achieved. Furthermore, since the engagement teeth of the jaw clutch have flat surfaces, direct engagement under static conditions where neither end rotates can easily lead to a "tooth-on-tooth" phenomenon, resulting in engagement failure.

[0028] Therefore, the existing technology lacks a control method that can reliably control the engagement of a dog clutch when there is no initial speed at either end of the dog clutch.

[0029] Please see Figure 1 In a first aspect, the present invention provides a clutch control method applied to a vehicle power system. The vehicle power system includes a first motor 1, a jaw clutch 2, and a first differential 3. The jaw clutch 2 has a first end face tooth and a second end face tooth that can be engaged. The first end face tooth is driven to the first motor 1, and the second end face tooth is driven to the first differential 3. The first differential 3 is in a stationary state.

[0030] For example, the first motor 1, the jaw clutch 2, and the first differential 3 are components included in the front axle drive mechanism of a vehicle powertrain. The front axle drive mechanism refers to the power transmission unit in a vehicle used to drive the front wheels, typically located in the front engine compartment. The first motor 1 converts electrical energy into mechanical energy to drive the vehicle, or, when driven by the engine 4, converts mechanical energy into electrical energy to generate electricity. The first differential 3 distributes the received power to the left and right front wheels, allowing them to rotate at different speeds to adapt to cornering conditions. The jaw clutch 2 selectively transmits power from the first motor 1 to the first differential 3, that is, selectively couples or decouples the first motor 1 from the front axle wheel system.

[0031] In some embodiments, the vehicle powertrain system further includes an engine 4, a wet clutch 5, an intermediate transmission structure 6, a transmission gear 7, and a drive shaft 8. The wet clutch 5 connects the engine 4 and the intermediate transmission structure 6. The intermediate transmission structure 6 is driven by the transmission gear 7. The transmission gear 7 is driven by the first motor 1. The transmission gear 7 is loosely fitted on the drive shaft 8. The drive shaft 8 is driven by the first differential 3. The first end face teeth of the jaw clutch 2 are connected to the transmission gear 7, and the second end face teeth of the jaw clutch 2 are connected to the drive shaft 8.

[0032] For example, when the engine 4 provides power for the vehicle's movement, both the wet clutch 5 and the jaw clutch 2 are engaged. The power of the engine 4 is transmitted to the transmission gear 7 via the wet clutch 5 and the intermediate transmission structure 6. The transmission gear 7 transmits the power to the drive shaft 8 via the jaw clutch 2, and then to the first differential 3 to drive the front wheels. At the same time, the transmission gear 7 also transmits the power to the motor, which can be selected to be in a rotating power generation state or in an idling state.

[0033] For example, when the motor starts the engine 4, the jaw clutch 2 disengages and the wet clutch 5 engages. The torque output by the first motor 1 is transmitted to the engine 4 through the transmission gear 7, the intermediate transmission structure 6, and the wet clutch 5, thus driving the engine 4 to speed up to the ignition speed.

[0034] For example, when the motor provides power for the vehicle's movement, the wet clutch 5 disengages and the jaw clutch 2 engages. The power of the first motor 1 is transmitted to the drive shaft 8 via the transmission gear 7 and the jaw clutch 2, and then to the first differential 3 to drive the front wheels.

[0035] For example, when the vehicle is powered by both the motor and the engine 4, the wet clutch 5 and the jaw clutch 2 are engaged, and the power of the engine 4 and the first motor 1 is coupled at the intermediate transmission structure 6 and transmitted together to the first differential 3 to drive the front wheels via the transmission gear 7, the jaw clutch 2, and the transmission shaft 8.

[0036] It is understood that the vehicle power system in this embodiment achieves free switching between multiple power transmission paths between the engine 4 and the first motor 1 through the cooperation of the wet clutch 5 and the dog clutch 2. The dog clutch 2, as a key component connecting the first motor 1 and the front axle wheel system, directly determines whether the first motor 1 participates in driving when it is engaged or disengaged. When the vehicle needs to switch from a parked state to a pure electric drive mode, the dog clutch 2 needs to engage under the condition that the first differential 3 is stationary (i.e., the second end face gear speed is zero). This is the application scenario of the clutch control method of this invention.

[0037] Please see Figure 2 The clutch control method of the present invention includes the following steps S100-S300: S100: In response to the engagement command, control the first motor to output starting torque so that the first end face tooth and the second end face tooth have a target speed difference.

[0038] For example, an engagement command refers to the command to engage the dog clutch, typically issued when the vehicle needs to switch from the current drive mode to a drive mode that requires the front axle motor. For instance, when the vehicle is parked and needs to start in pure electric four-wheel drive mode, the vehicle controller determines that the dog clutch needs to be engaged first to establish a power transmission path from the first motor to the front wheels, and then generates an engagement command and sends it to the motor controller.

[0039] For example, the starting torque is the torque acting on the first end face tooth to rotate it, output by the first motor and transmitted to the first end face tooth via a transmission gear. The magnitude of the starting torque must be sufficient to overcome the shaft frictional resistance between the first motor and the first end face tooth, and to accelerate the first end face tooth to the target speed. The starting torque can be a brief pulse torque used to quickly establish the target speed difference; or it can be a combination of a pulse torque and a subsequent holding torque used to maintain the target speed difference after it has been established.

[0040] For example, since the first differential is stationary (i.e., the vehicle is parked) and the second end face tooth is stationary, the speed difference between the first and second end face teeth is the speed of the first end face tooth. The speed of the first end face tooth can be indirectly obtained through the speed sensor of the first motor. Because there is a definite transmission ratio between the first motor and the first end face tooth, the controller can calculate the speed of the first end face tooth based on the real-time speed of the first motor and the transmission ratio.

[0041] For example, the target speed difference refers to the speed difference suitable for the engagement of the first end face tooth and the second end face tooth. If the speed difference is too small, it is difficult for the end face teeth of the first and second end face teeth to be misaligned, resulting in a low engagement success rate; if the speed difference is too large, it will generate greater impact and noise during engagement and may damage the end face teeth. The specific value of the target speed difference needs to be calibrated and determined based on factors such as the tooth profile parameters and engagement time of the jaw clutch, and can be set between 20 rpm and 50 rpm.

[0042] It is understood that this embodiment controls the first motor to output starting torque in response to the engagement command. Under the condition that the first differential is stationary and the second end face tooth speed is zero, the first end face tooth is actively driven to rotate, thereby creating a target speed difference between the first end face tooth and the second end face tooth. The existence of the target speed difference allows the first end face tooth and the second end face tooth to be staggered during the engagement process, so that the first end face tooth and the second end face tooth can smoothly slide into the meshing position. This solves the technical problem of the prior art that the dog clutch cannot be reliably engaged in the parking state because there is no speed at both ends of the clutch.

[0043] Please see Figure 3 In some embodiments, the starting torque includes a first pulse torque and a holding torque; step S100 specifically includes S110-S120: S110: Control the first motor to output the first pulse torque so that the first end face tooth and the second end face tooth generate a target speed difference.

[0044] For example, the first pulse torque is a short-term torque output used to rapidly accelerate the first end face tooth from a stationary state to the target speed. Its amplitude must be sufficient to overcome the shaft friction resistance between the first motor and the first end face tooth, and to accelerate the first end face tooth to the target speed in a short time.

[0045] For example, the output of the first pulse torque can be achieved by the motor controller applying a short-duration high current command to the first motor, the amplitude and duration of which are pre-calibrated based on the target speed difference and the moment of inertia of the first motor.

[0046] For example, the specific value of the first pulse torque can be determined based on the target speed difference. For instance, the required torque is calculated using dynamic formulas based on the first motor's moment of inertia and the target acceleration time, and then calibrated and corrected during bench testing. The higher the target speed difference, the greater the required first pulse torque; the greater the first motor's moment of inertia, the greater the required first pulse torque. It should be explained that the first motor's moment of inertia refers to the equivalent moment of inertia formed by the first motor rotor and its fixedly connected rotating components such as transmission gears. Since the first pulse torque acts directly on the first motor rotor, and there is a fixed transmission connection between the first motor and the first end face gears, the first motor's moment of inertia is a key parameter determining the torque required for acceleration.

[0047] It is understandable that the reason why this embodiment uses a first pulse torque instead of a continuous large torque output is that the first pulse torque can quickly make the first end face tooth reach the target speed in a short time, thereby quickly establishing the required target speed difference and shortening the engagement preparation time; at the same time, the first pulse torque is removed after it ends, avoiding the possibility that the first end face tooth speed may be excessively increased or that the shaft system may be subjected to unnecessary impact due to continuous large torque output, thereby generating noise.

[0048] S120: Control the first motor to continuously output holding torque so that the speed difference between the first end face tooth and the second end face tooth is maintained at the target speed difference; the holding torque is less than the first pulse torque.

[0049] For example, the holding torque is a small torque output used to overcome the shaft frictional resistance between the first motor and the first end face tooth, allowing the first end face tooth to maintain its current speed without acceleration torque. It should be explained that due to losses in the shaft system such as bearing friction, gear meshing friction, and lubricating oil viscous resistance, if torque is not continuously applied, the speed of the first end face tooth will gradually decrease under the action of shaft frictional resistance, causing the speed difference to disappear. In this embodiment, the holding torque is equal to these shaft frictional resistances, enabling the first end face tooth to maintain a uniform speed, thereby stably maintaining the speed difference near the target speed difference.

[0050] For example, the specific value of the holding torque can be determined based on the shaft friction resistance between the first motor and the first end face teeth. It can be a set value, such as the average friction resistance obtained from bench calibration, which is set to 1~3Nm; or it can be adaptively adjusted according to real-time working conditions.

[0051] In some embodiments, the holding torque is determined by the following steps: obtaining the real-time frictional resistance from the first motor to the first end face teeth; calculating the base torque required to overcome the real-time frictional resistance, and using the base torque as the holding torque.

[0052] For example, the real-time frictional resistance from the first motor to the first end face tooth refers to the sum of the frictional resistances of all rotating components along the power transmission path, including motor bearing friction, gear meshing friction, and transmission shaft bearing friction. Since shaft frictional resistance may change due to factors such as oil temperature, speed variation, and component wear, the real-time frictional resistance is not a constant value. For example, the real-time frictional resistance can be indirectly estimated through the speed decay curve of the first motor in a zero-torque state, or calculated using a pre-calibrated frictional resistance model combined with current oil temperature, speed, and other parameters; details will not be elaborated here.

[0053] For example, the base torque can be determined based on the real-time frictional resistance. The base torque enables the first end face tooth to maintain a constant rotational speed without accelerating torque. It should be explained that in this embodiment, the base torque is used as the holding torque. Its function is to overcome the real-time frictional resistance without producing an additional acceleration effect, thereby stabilizing the rotational speed of the first end face tooth near the target rotational speed and keeping the rotational speed difference between the first end face tooth and the second end face tooth constant.

[0054] Understandably, this embodiment divides the starting torque into two stages: a first pulse torque and a holding torque. The first pulse torque is used to accelerate the first end face tooth to the target speed in a short time, establishing the required target speed difference. The holding torque is used to continuously overcome shaft friction resistance after the target speed difference is established, preventing the speed difference from decaying due to frictional losses, thereby ensuring the stability of the speed difference during the engagement of the jaw clutch. Furthermore, if a single, continuous high torque output is used, the speed of the first end face tooth will continuously increase, resulting in an excessively large speed difference. This would lead to violent collisions of the end face teeth during engagement, generating significant impact noise. In contrast, this embodiment quickly establishes the target speed difference using the first pulse torque and then switches to a small holding torque, stabilizing the speed difference within the target range. This avoids violent collisions caused by excessively high speeds, thereby reducing engagement noise and improving driving comfort.

[0055] Please see Figure 4 In some embodiments, step S120 specifically includes S121-S122: S121: Control the first motor to continuously output holding torque, and determine whether the speed difference between the first end face teeth and the second end face teeth is the target speed difference.

[0056] For example, to determine whether the speed difference is the target speed difference, the real-time speed of the first motor can be obtained and the speed of the first end face tooth can be calculated. Then, this speed is compared with the target speed difference. It should be explained that since the second end face tooth is stationary, the speed of the first end face tooth is the actual speed difference. If the actual speed of the first end face tooth is within the target speed difference, it is determined that the speed difference has been maintained at the target speed difference; if the actual speed deviates from the target speed difference, it is determined that the speed difference has not been maintained at the target speed difference. For example, the target speed difference is 20 rpm to 50 rpm.

[0057] S122: If not, repeat steps S110 and S121 until the speed difference between the first end face tooth and the second end face tooth is maintained at the target speed difference.

[0058] For example, if the determination result is that the speed difference is not maintained at the target speed difference, for example, due to fluctuations in shaft friction resistance causing the speed to drop below the target speed difference, then step S110 is executed again, the first pulse torque is output again to accelerate the first end face tooth to the target speed, and then the holding torque is output again and it is determined whether the speed difference is maintained at the target speed difference. This cycle is repeated until the speed difference between the first end face tooth and the second end face tooth is stably maintained within the target speed difference.

[0059] For example, the number of times steps S110 and S121 are repeated can be set to an upper limit according to the actual situation. If the speed difference cannot be maintained at the target speed difference even if the upper limit is exceeded, it can be determined that there is an abnormality in the system and a fault alarm message will be output.

[0060] It is understood that this embodiment, through the judgment step of S121 and the repeated execution step of S122, constitutes a closed-loop control logic for establishing and maintaining the target speed difference. During the torque output period, the actual speed difference between the first end face tooth and the second end face tooth is continuously monitored to see if it deviates from the target speed difference. If it deviates, the first pulse torque is reapplied for compensation, thereby ensuring that the speed difference remains stable at the target speed difference before and during the engagement action of the jaw clutch. This effectively overcomes the problem of speed difference drift between the first end face tooth and the second end face tooth caused by interference factors such as shaft friction resistance fluctuations and oil temperature changes, ensuring the stability and reliability of the engagement conditions of the jaw clutch.

[0061] S200: Controls the engagement action of the jaw clutch.

[0062] Understandably, after step S100 drives the first end face tooth and the second end face tooth to have a target speed difference, step S200 controls the jaw clutch to perform an engagement action, that is, energizes the electromagnetic actuator of the jaw clutch, causing it to push the first end face tooth and / or the second end face tooth to move axially, approaching and engaging with the opposite end face tooth. Since there is a target speed difference between the first end face tooth and the second end face tooth at this time, during their relative rotational motion, the tooth tip and tooth groove of the end face tooth have a chance to align, thereby allowing the end face tooth to smoothly slide into the engagement position and complete the engagement.

[0063] S300: Obtain the output speed of the first motor. If the output speed is not zero, repeat steps S100 and S200 until the output speed is zero and the jaw clutch is engaged.

[0064] For example, after the jaw clutch is controlled to perform the engagement action in step S200, step S300 obtains the output speed of the first motor and determines whether the speed is zero. If the output speed is not zero, it indicates that the first end face tooth and the second end face tooth have not successfully meshed, and the first motor can still rotate freely. At this time, it is necessary to re-execute step S100 to establish the speed difference and step S200 to perform the engagement action until the output speed drops to zero.

[0065] Understandably, if the jaw clutch engages successfully, the first motor connects to the first differential. The starting torque output by the first motor is insufficient to rotate the stationary first differential, thus the output speed of the first motor is rapidly reduced to zero. Therefore, by monitoring whether the output speed of the first motor is zero, it can be determined whether the jaw clutch has successfully engaged. If the output speed is zero, engagement is considered complete; if the output speed is not zero, engagement is considered failed, and the engagement process needs to be repeated.

[0066] Please see Figure 5 In some embodiments, step S300 specifically includes S310-S320: S310: Obtain the first output speed of the first motor. If the first output speed is not zero, repeat steps S100 and S200 until the first output speed is zero.

[0067] For example, after the jaw clutch is controlled to perform the engagement action in step S200, step S310 obtains the first output speed of the first motor and determines whether the speed is zero. If the first output speed is not zero, it indicates that the first end face tooth and the second end face tooth have not successfully meshed, and the first motor can still rotate freely. At this time, it is necessary to re-execute step S100 to establish the speed difference and step S200 to perform the engagement action until the first output speed drops to zero.

[0068] S320: Control the first motor to output the second pulse torque, obtain the second output speed of the first motor. If the second output speed is not zero, repeat steps S100 and S200 until the second output speed is zero, and the jaw clutch engagement is completed.

[0069] If the first output speed is determined to be zero in step S310, it means that the first end face tooth and the second end face tooth may have successfully meshed, but there may also be a situation where the end face teeth have made contact but are not fully engaged, resulting in a partial engagement. In this embodiment, step S320 is executed after step S310 to control the first motor to output the second pulse torque, obtain the second output speed of the first motor, and determine whether the speed is zero, in order to verify whether the jaw clutch is truly fully engaged. If the second output speed is zero, the verification is passed, and the engagement is confirmed to be reliable; if the second output speed is not zero, the verification fails, indicating that the engagement is unreliable, and the engagement process needs to be repeated.

[0070] It is understandable that in this embodiment, in step S310, the output speed of the first motor under the holding torque is monitored to determine whether the jaw clutch has completed mechanical engagement; in step S320, an additional second pulse torque is applied to the first motor for secondary verification to confirm whether the engagement is truly reliable and whether there is any false engagement, thus ensuring the reliability and safety of the jaw clutch engagement.

[0071] In some embodiments, there is shaft frictional resistance between the first motor and the teeth on the first end face; the second pulse torque is greater than or equal to the base torque, which is the torque required to overcome the shaft frictional resistance.

[0072] For example, the second pulse torque is a verification torque used to confirm the reliable engagement of the jaw clutch. Its magnitude must be sufficient to overcome the frictional resistance of the shaft system, enabling the first motor to produce a detectable change in speed even when the clutch is not fully engaged. If the second pulse torque is less than the base torque, the first motor may not be able to rotate even if the clutch is not engaged because the torque is insufficient to overcome the frictional resistance, leading to a false judgment of successful engagement.

[0073] For example, the second pulse torque is less than or equal to a set upper limit value, which is the first motor output torque required for the vehicle to move when the jaw clutch is engaged. This set upper limit value can be determined through calculation or experimentation based on parameters such as vehicle load and gear ratio, to ensure that the second pulse torque is insufficient to move the vehicle when the clutch is reliably engaged, thereby avoiding vehicle body swaying and impact. For example, after determining that the second output speed is zero, the engagement of the jaw clutch is completed, and then subsequent drive mode switching operations can be performed, such as controlling the output drive torque of the first motor to enable the vehicle to start and drive in pure electric four-wheel drive mode.

[0074] Secondly, the present invention provides a gear shifting method in which, in parking mode, in response to a pure electric mode switching command, the engagement of a dog clutch is controlled by the clutch control method of the first aspect.

[0075] For example, the pure electric mode switching command refers to the command generated when the vehicle switches from the current non-pure electric drive mode to the pure electric drive mode. For instance, when the vehicle is parked and the driver selects the pure electric four-wheel drive mode via the driving mode selection knob, the vehicle controller generates a pure electric mode switching command, indicating that the dog clutch needs to be engaged to establish the power transmission path for the front axle motor.

[0076] For example, the pure electric mode includes pure electric four-wheel drive mode and pure electric front-wheel drive mode. Pure electric four-wheel drive mode refers to the mode in which the first motor on the front axle and the second motor on the rear axle drive the vehicle simultaneously. In this mode, the front axle needs to engage a dog clutch to allow the power of the first motor to be transmitted to the front wheels. Pure electric front-wheel drive mode refers to the mode in which only the first motor on the front axle drives the vehicle. In this mode, the dog clutch also needs to be engaged to establish a power transmission path from the first motor to the front wheels.

[0077] It is understood that this embodiment is applied in parking mode. Under the condition that the vehicle is stationary and there is no initial speed at both ends of the dog clutch, the dog clutch is reliably engaged, thereby providing the necessary mechanical connection conditions for the vehicle to switch from parking state to pure electric drive mode, and solving the technical problem that the dog clutch cannot be reliably engaged in the parking state in the prior art.

[0078] Thirdly, this invention provides a gear shifting method applied to a vehicle powertrain system. The vehicle powertrain system includes a first motor, a second motor, a jaw clutch, a first differential, and a second differential. The second motor is driven by the second differential, and both the first and second differentials are in a stationary state. The vehicle gear shifting method includes: In response to the pure electric four-wheel drive mode switching command, the engagement of the jaw clutch is controlled by the first aspect of the clutch control method.

[0079] For example, the first differential is used to drive the front wheels of the vehicle, and the second differential is used to drive the rear wheels of the vehicle. Both the first and second differentials are in a stationary state, that is, the vehicle is in a parked state, and neither the front nor rear wheels are rotating. At this time, the speed of the second end face teeth of the dog clutch is zero, and the speed of the first end face teeth is also zero.

[0080] For example, pure electric four-wheel drive mode refers to a mode in which the first motor on the front axle and the second motor on the rear axle simultaneously drive the vehicle, allowing the vehicle to travel in four-wheel drive mode. When switching to pure electric four-wheel drive mode while the vehicle is parked, the dog clutch must first be engaged to establish a connection between the first motor and the first differential, while the second motor remains connected to the second differential, thereby enabling both the front and rear axles to have driving force simultaneously.

[0081] It is understood that this embodiment is designed for a typical application scenario where a four-wheel drive hybrid vehicle switches to pure electric four-wheel drive mode while parked. It reliably controls the engagement of the dog clutch when both the front and rear axles are stationary, providing technical assurance for the vehicle to start in pure electric four-wheel drive mode.

[0082] Reference Figure 6 Fourthly, the present invention provides a vehicle including a controller 401, which includes one or more processors 410, a memory 420, and interfaces for connecting the various components, including high-speed interfaces and low-speed interfaces. The various components are interconnected via different buses and can be mounted on a common motherboard or otherwise installed as needed. The processors can process instructions executed within a computer device, including instructions stored in or on memory to display graphical information of a GUI on an external input / output device (such as a display device coupled to the interface). In some alternative embodiments, multiple processors and / or multiple buses can be used with multiple memories and multiple memory modules, if desired. Similarly, multiple computer devices can be connected, each providing some of the necessary operations (e.g., as a server array, a group of blade servers, or a multiprocessor system). Figure 4 Take a processor 410 as an example.

[0083] Processor 410 may be a central processing unit, a network processor, or a combination thereof. Processor 410 may further include a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The programmable logic device may be a complex programmable logic device (CAMP), a field-programmable gate array (FPGA), a general-purpose array logic (GDA), or any combination thereof.

[0084] The memory 420 stores instructions executable by at least one processor 410 to cause the at least one processor 410 to perform actions to implement the clutch control method described in the first aspect and / or the shifting method described in the second and third aspects.

[0085] The memory 420 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created based on the use of the computer device as shown by a landing page for an app. Furthermore, the memory 420 may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some alternative embodiments, the memory 420 may optionally include memory remotely located relative to the processor 410, and these remote memories may be connected to the computer device via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0086] The memory 420 may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as flash memory, hard disk or solid-state drive; the memory 420 may also include a combination of the above types of memory.

[0087] The controller also includes a communication interface 430 for the control unit to communicate with other devices or communication networks.

[0088] Fifthly, the present invention provides a computer storage medium storing program code, which is loaded and executed by a processor to implement the clutch control method described above.

[0089] In this embodiment, the readable storage medium can be any tangible medium that contains or stores a program that can be used by or in conjunction with an instruction execution system, apparatus, or device.

[0090] A readable medium can be a readable signal medium or a readable storage medium. A readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination thereof. More specific examples of readable storage media (a non-exhaustive list) include: an electrical connection having one or more wires, a portable disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0091] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, carrying readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A readable signal medium may also be any readable medium other than a readable storage medium, capable of sending, propagating, or transmitting programs for use by or in conjunction with an instruction execution system, apparatus, or device.

[0092] The program code contained on the readable medium may be transmitted using any suitable medium, including but not limited to wireless, wired, optical fiber, RE, etc., or any suitable combination thereof.

[0093] Program code for performing the operations of this invention can be written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Java and C++, as well as conventional procedural programming languages ​​such as C or similar languages. The program code can execute entirely on the user's computing device, partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server. In cases involving remote computing devices, the remote computing device can be connected to the user's computing device via any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computing device (e.g., via the Internet using an Internet service provider).

[0094] In a sixth aspect, the present invention provides a computer program product comprising computer instructions stored in a computer-readable storage medium and adapted to be read and executed by a processor to cause a computer device having a processor to perform the clutch control method described above.

[0095] In one embodiment, the computer program product can be a tangible product containing a computer program, such as a computer-readable storage medium storing the computer program. The readable storage medium can be a storage medium based on electrical, magnetic, optical, electromagnetic, infrared, or other signals, including but not limited to: random access memory (RAM), read-only memory (ROM), magnetic tape, floppy disk, flash memory, hard disk drive (HDD), solid-state drive (SSD), etc. For example, the computer program product can be implemented as a non-volatile storage medium storing the computer program, such as read-only memory, NAND flash memory, etc.

[0096] In one implementation, the computer program product can be an intangible product containing a computer program. For example, the computer program product can be implemented as a virtual digital product, such as an executable file, installation package, or other digital file storing the computer program.

[0097] Computer program code can be written in one or more programming languages. Examples of programming languages ​​include C, Java, C++, and Python. Program code can execute entirely on the user's computing device, partially on the user's computing device, or as a standalone software package. It can also execute partially on the user's computing device and partially on a remote computing device, or entirely on a remote computing device or server. In cases involving remote computing devices, the remote computing device can be connected to the user's computing device via any type of network, such as a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computing device (e.g., via an internet connection provided by a mobile network operator).

[0098] Computer programs can be carried or transmitted via signals such as electricity, magnetism, light, electromagnetic radiation, and infrared rays. Electronic devices can convert signals carrying computer programs into digital signals, thereby running the computer programs. When a computer program runs on an electronic device, its code is used to cause the electronic device to execute (more specifically, the processor of the electronic device to execute) the method steps of various exemplary embodiments of this application, such as executing the clutch control method of the first aspect and / or the gear shifting methods of the second and third aspects described above.

[0099] Reference Figure 7 In a seventh aspect, the present invention provides an electronic device, comprising: Memory 520 is used to store computer programs; Processor 510 is used to execute computer programs stored in memory to implement the clutch control method described above.

[0100] The following is for reference Figure 5 The electronic device is illustrated by way of a general-purpose computing device. It should be understood that... Figure 5 The electronic device 500 shown is merely an example and should not be construed as limiting the functionality and scope of use of the embodiments described in this application.

[0101] like Figure 5 As shown, the electronic device 500 may include: a processor 510, a memory 520, a bus 530, an I / O (input / output) interface 540, a network adapter 550, and a display 560.

[0102] Memory 520 may include volatile memory, such as RAM 521 and cache unit 522, and may also include non-volatile memory, such as ROM 523. Memory 520 may also include one or more program modules 524, including but not limited to: operating system, one or more application programs, other program modules, and program data. Each or some combination of these examples may include an implementation of a network environment. For example, program module 524 may include the modules in the above-described apparatus.

[0103] The processor 510 may include one or more processing units, such as an AP (Application Processor), a modem processor, a GPU (Graphics Processing Unit), an ISP (Image Signal Processor), a controller, an encoder, a decoder, a DSP (Digital Signal Processor), a baseband processor, and / or an NPU (Neural-Network Processing Unit).

[0104] The processor 510 can be used to execute executable instructions stored in the memory 520, such as the clutch control method of the first aspect and / or the shifting methods of the second and third aspects.

[0105] Bus 530 is used to connect different components of electronic device 500 and may include a data bus, an address bus and a control bus.

[0106] Electronic device 500 can communicate with one or more external devices 570 (such as keyboard, mouse, external controller, etc.) through I / O interface 540.

[0107] Electronic device 500 can communicate with one or more networks via network adapter 550. For example, network adapter 550 can provide mobile communication solutions such as 3G / 4G / 5G, or wireless communication solutions such as wireless LAN, Bluetooth, and near-field communication. Network adapter 550 can communicate with other modules of electronic device 500 via bus 530.

[0108] Electronic device 500 can display a graphical user interface via display 560.

[0109] although Figure 5As not shown in the diagram, other hardware and / or software modules may also be configured in the electronic device 500, including but not limited to: microcode, device drivers, redundant processors, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.

[0110] It should be noted that although the steps of the method in this application are described in a specific order in the accompanying drawings, this does not require or imply that the steps must be performed in that specific order, or that all the steps shown must be performed to achieve the desired result. Additional or alternative steps may be omitted, multiple steps may be combined into one step, and / or one step may be broken down into multiple steps.

[0111] Furthermore, the above figures are merely illustrative of the processes included in the method according to exemplary embodiments of this application, and are not intended to be limiting. It is readily understood that the processes shown in the above figures do not indicate or limit the temporal order of these processes. Additionally, it is readily understood that these processes may be executed synchronously or asynchronously, for example, in multiple modules.

[0112] As can be seen from the above, the technical solution of this application can be implemented as a method, system, computer program product, computer-readable storage medium, electronic device, etc. Those skilled in the art will understand that various aspects of this application can be specifically implemented in the following forms: a completely hardware implementation, a completely software implementation (including firmware, microcode, etc.), or an implementation combining hardware and software aspects, which may be referred to as "circuit", "module" or "device" respectively.

[0113] It should be understood that this application is not limited to the specific methods, steps, or structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. Those skilled in the art will readily conceive of other embodiments based on the specific implementations provided in this application. Therefore, the specific implementations provided in this application are merely exemplary, and the scope and spirit of this application are indicated by the claims, and should cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary technical means in the art not disclosed in this application.

[0114] The above examples are merely illustrative of the technical content of the present invention to facilitate easier understanding by the reader, but do not imply that the implementation of the present invention is limited to these examples. Any technical extensions or re-creations made based on the present invention are protected by the present invention. The scope of protection of the present invention is defined by the claims.

Claims

1. A clutch control method, characterized in that, The method is applied to a vehicle powertrain system, which includes a first motor, a jaw clutch, and a first differential. The jaw clutch has engaging first end face teeth and second end face teeth. The first end face teeth are drive-connected to the first motor, and the second end face teeth are drive-connected to the first differential. The first differential is in a stationary state. The clutch control method includes the following steps: In response to the engagement command, the first motor is controlled to output starting torque so that the first end face tooth and the second end face tooth have a target speed difference; Control the jaw clutch to perform the engagement action; The output speed of the first motor is obtained. If the output speed is not zero, the first motor is controlled to output the starting torque again, and the jaw clutch is controlled to perform the engagement action until the output speed is zero, and the jaw clutch engagement is completed.

2. The clutch control method according to claim 1, characterized in that, The starting torque includes a first pulse torque and a holding torque; controlling the first motor to output the starting torque so that the first end face teeth and the second end face teeth have a target speed difference includes: The first motor is controlled to output the first pulse torque so that the first end face tooth and the second end face tooth generate the target speed difference; The first motor is controlled to continuously output the holding torque so that the speed difference between the first end face tooth and the second end face tooth is maintained at the target speed difference; the holding torque is less than the first pulse torque.

3. The clutch control method according to claim 2, characterized in that, The holding torque is determined through the following steps: Obtain the real-time frictional resistance from the first motor to the first end face teeth; Calculate the base torque required to overcome the real-time frictional resistance, and use the base torque as the holding torque.

4. The clutch control method according to claim 2, characterized in that, Controlling the first motor to continuously output the holding torque so that the speed difference between the first end face tooth and the second end face tooth is maintained at the target speed difference includes: Control the first motor to continuously output the holding torque, and determine whether the speed difference between the first end face tooth and the second end face tooth is the target speed difference; If not, the first motor is controlled to output the first pulse torque and the holding torque again, and the speed difference between the first end face tooth and the second end face tooth is re-determined to be the target speed difference until the speed difference between the first end face tooth and the second end face tooth is maintained at the target speed difference.

5. The clutch control method according to any one of claims 1-4, characterized in that, Obtain the output speed of the first motor. If the output speed is not zero, re-control the first motor to output the starting torque and control the jaw clutch to perform the engagement action until the output speed is zero, at which point the jaw clutch engagement is complete. This includes: The first output speed of the first motor is obtained. If the first output speed is not zero, the first motor is controlled to output the starting torque and the jaw clutch is controlled to perform an engagement action until the first output speed is zero. When the first output speed is zero, the first motor is controlled to output a second pulse torque and the second output speed of the first motor is obtained. If the second output speed is not zero, the first motor is controlled to output the starting torque again and the jaw clutch is controlled to perform the engagement action until the second output speed is zero and the jaw clutch engagement is completed.

6. The clutch control method according to claim 5, characterized in that, There is shaft frictional resistance between the first motor and the teeth on the first end face; the second pulse torque is greater than or equal to the base torque, which is the torque required to overcome the shaft frictional resistance.

7. A gear shifting method, characterized in that, In parking mode, in response to the pure electric mode switching command, the clutch control method according to any one of claims 1-6 is used to control the engagement of the dog clutch.

8. A gear shifting method, characterized in that, This method is applied to a vehicle powertrain system, which includes a first motor, a second motor, a jaw clutch, a first differential, and a second differential. The second motor is driven by the second differential, and both the first and second differentials are in a stationary state. The vehicle shifting method includes: In response to a pure electric four-wheel drive mode switching command, the engagement of the jaw clutch is controlled by the clutch control method according to any one of claims 1-6.

9. A vehicle, characterized in that, include: A controller comprising: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the computer instructions to implement the clutch control method of any one of claims 1-6 and / or the gear shifting method of any one of claims 7-8.

10. A computer storage medium, characterized in that, The computer storage medium stores program code, which is loaded and executed by a processor to implement the clutch control method as described in any one of claims 1-6 and / or the gear shifting method as described in any one of claims 7-8.

11. A computer program product, characterized in that, The computer program product includes computer instructions stored in a computer-readable storage medium and adapted to be read and executed by a processor to cause a computer device having the processor to perform the clutch control method as claimed in any one of claims 1-6 and / or the gear shifting method as claimed in any one of claims 7-8.

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