P2 hybrid commercial vehicle clutch torque self-learning method and system

Abstract

The invention belongs to the technical field of automobiles, and relates to a P2 hybrid commercial vehicle clutch torque self-learning method and system. After the motor and the engine are started, the rotating speeds of the motor and the engine are controlled to be stabilized at the corresponding target rotating speeds. Then, a clutch is controlled to be closed, in the clutch closing process, the rotating speed of the engine is controlled to be maintained at the target rotating speed of the engine, and the motor angular acceleration, the motor torque, the motor rotational inertia and the clutch displacement are obtained in real time; and torque transmitted by a clutch is obtained according to the motor angular acceleration, the motor torque and the motor rotational inertia. And after the motor torque reaches a set torque threshold value, a clutch transmission torsion line is formed according to the clutch displacement and the torque transmitted by the clutch. According to the method, the torque transmitted by the clutch can be accurately calculated, an accurate transmission torsion line is formed, the smoothness of power connection before and after vehicle gear shifting is ensured, and full automation of the whole self-learning process is achieved.

Description

Technical Field

[0001] This invention belongs to the field of automotive technology and relates to a method and system for self-learning clutch torque in P2 hybrid commercial vehicles. Background Technology

[0002] In the automotive industry, the clutch, as a key component of power transmission, directly affects the shifting quality and driving experience of a vehicle. Due to variations in manufacturing precision during production, potential assembly deviations during installation, and inevitable wear and tear on various components after long-term vehicle use, the torque transmission characteristics of the clutch in each vehicle are unique and not entirely consistent. Failure to accurately correct the clutch torque curve can lead to uneven power delivery before and after gear shifts, severely impacting the driving experience. In traditional AMT commercial vehicles, during start-up, the torque characteristic curve can be estimated and corrected using clutch slippage to determine the correspondence between the clutch's transmitted torque and its position.

[0003] However, P2 hybrid commercial vehicles mostly operate in pure electric mode during start-up, in which case the clutch remains disengaged and does not slip. This means that P2 hybrid commercial vehicles cannot correct the clutch transmission torque curve through clutch slippage, unlike traditional AMT commercial vehicles.

[0004] Therefore, it is essential to study a method for self-learning clutch torque in P2 hybrid commercial vehicles. Summary of the Invention

[0005] The purpose of this invention is to provide a method and system for self-learning clutch torque in P2 hybrid commercial vehicles, so as to solve the technical problem that P2 hybrid commercial vehicles cannot correct the torque transmission characteristics of the clutch.

[0006] To achieve the above objectives, the present invention employs the following technical solution: In a first aspect, the present invention provides a method for self-learning clutch torque in a P2 hybrid commercial vehicle, comprising the following steps: In response to the clutch torque self-learning function activation command triggered when the vehicle is parked and stationary and the gear is in N, a motor start command is sent, and after the motor starts, the motor drives the engine to start through the clutch. After the engine starts, a clutch disengagement command is sent; After the clutch disengages, the speed of the motor is controlled to be stabilized at the target speed of the motor, and the speed of the engine is controlled to be stabilized at the target speed of the engine. The clutch is controlled to close. During the clutch closure process, the engine speed is controlled to be maintained at the target engine speed, and the motor angular acceleration, motor torque, motor rotational inertia and clutch displacement are acquired in real time. The torque transmitted by the clutch is obtained based on the motor angular acceleration, the motor torque and the motor rotational inertia. After the motor torque reaches the set torque threshold, a clutch transmission twist line is formed based on the clutch displacement and the torque transmitted by the clutch.

[0007] Secondly, the present invention provides a system for self-learning clutch torque in a P2 hybrid commercial vehicle, comprising: The motor start control module is used to send a motor start command in response to the clutch torque self-learning function activation command triggered when the vehicle is in a parked and stationary state and the gear is in N gear. After the motor starts, the motor drives the engine to start through the clutch. The clutch disengagement control module is used to send a clutch disengagement command after the engine is started; The speed control module is used to control the speed of the motor to stabilize at the target speed of the motor after the clutch is disengaged, and to control the speed of the engine to stabilize at the target speed of the engine. The data acquisition module is used to control the clutch engagement. During the clutch engagement process, the engine speed is controlled to be maintained at the target engine speed, and the motor angular acceleration, motor torque, motor rotational inertia and clutch displacement are acquired in real time. The torque transmitted by the clutch is obtained based on the motor angular acceleration, the motor torque and the motor rotational inertia. The transmission twist line acquisition module is used to form a clutch transmission twist line based on the clutch displacement and the torque transmitted by the clutch after the motor torque reaches a set torque threshold.

[0008] Compared with the prior art, the present invention has the following beneficial effects: When the vehicle is parked and in neutral (N) gear, this invention, in response to a clutch torque self-learning function activation command, sends a motor start command. After the motor starts, it drives the engine via the clutch, creating initial conditions for subsequent clutch torque self-learning. After the engine starts, a clutch disengagement command is sent, disengaging the clutch and cutting off power transmission between the engine and motor. After clutch disengagement, the motor speed and engine speed are stabilized at a target speed, providing a stable reference environment for torque measurement during subsequent clutch engagement. Then, the clutch is controlled to engage. During clutch engagement, the engine speed is maintained at the target speed, and the motor angular acceleration, motor torque, motor moment of inertia, and clutch displacement are acquired in real time. The torque transmitted by the clutch is obtained based on the motor angular acceleration, motor torque, and motor moment of inertia. By maintaining a stable engine speed, the relationship between changes in motor parameters and clutch torque can be analyzed more clearly. Precise calculations of parameters such as motor angular acceleration, torque, and moment of inertia accurately reflect the magnitude of torque transmitted by the clutch at different positions, providing crucial data for forming an accurate clutch transmission torque curve. After the motor torque reaches a set torque threshold, a clutch transmission torque curve is formed based on the clutch displacement and the torque transmitted by the clutch. The clutch transmission torque curve visually demonstrates the relationship between the clutch-transmitted torque and the clutch position, providing a basis for accurate clutch control during subsequent gear shifts. This invention can accurately calculate the torque transmitted by the clutch and form an accurate transmission torque curve, ensuring smooth power transitions before and after gear shifts. During gear shifts, controlling the clutch based on the accurate transmission torque curve effectively avoids power interruption or shock, greatly improving driving comfort. This invention employs a vehicle-wide communication control method, achieving full automation of the entire self-learning process through communication between the hybrid transmission TCU, vehicle controller HCU, engine ECU, and motor MCU. This avoids the influence of human factors on the self-learning results, improving the accuracy and reliability of self-learning.

[0009] The system of this invention includes a motor start control module, a clutch disengagement control module, a speed control module, a data acquisition module, and a transmission torque curve acquisition module. The motor start control module, in response to a clutch torque self-learning function activation command triggered when the vehicle is parked and in neutral (N) gear, sends a motor start command. After the motor starts, it drives the engine to start via the clutch. The clutch disengagement control module, after the engine starts, sends a clutch disengagement command. The speed control module, after the clutch disengages, controls the motor speed to stabilize at a target motor speed and the engine speed to stabilize at a target engine speed. The data acquisition module controls the clutch engagement, maintaining the engine speed at the target engine speed during clutch engagement and acquiring motor angular acceleration, motor torque, motor moment of inertia, and clutch displacement in real time. It then obtains the torque transmitted by the clutch based on the motor angular acceleration, motor torque, and motor moment of inertia. The transmission torque curve acquisition module, after the motor torque reaches a set torque threshold, generates a clutch transmission torque curve based on the clutch displacement and the torque transmitted by the clutch, controls the clutch to return to the engaged state, and controls the engine to shut off. The various modules work together to accurately calculate the torque transmitted by the clutch and form an accurate transmission torque curve, ensuring the smoothness of power connection before and after gear shifts and realizing full automation of the entire self-learning process. Attached Figure Description

[0010] Figure 1 This is a flowchart of the method of the present invention; Figure 2 This is a system module diagram of the present invention; Figure 3 This is the P2 hybrid power roadmap of the present invention; Figure 4 This is a schematic diagram of the topology of the P2 hybrid commercial vehicle transmission system of the present invention; Figure 5 This is a control flowchart of the present invention; Figure 6 This is the actual vehicle clutch torque self-learning data for the present invention; Figure 7 This refers to the torque transmission characteristics of the clutch before and after self-learning, as described in this invention. Detailed Implementation

[0011] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. 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 should fall within the scope of protection of the present invention.

[0012] It should be noted that the terms "first," "second," etc., in the specification and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0013] The present invention will now be described in further detail with reference to the accompanying drawings: Example 1: See Figure 1 This invention discloses a method for self-learning clutch torque in P2 hybrid commercial vehicles. It should be noted that P2 refers to a hybrid system configuration where the electric motor is located between the engine and the transmission. The method includes the following steps: S1, in response to the clutch torque self-learning function activation command triggered when the vehicle is parked and stationary and the gear is in N, sends a motor start command. After the motor starts, the motor drives the engine to start through the clutch, creating initial conditions for subsequent clutch torque self-learning. This ensures that the self-learning process is carried out in a relatively stable and safe environment, avoiding interference from various dynamic factors during vehicle operation on the self-learning results, and laying the foundation for accurately obtaining clutch torque data.

[0014] In this embodiment of the invention, step S1 includes: In response to the clutch torque self-learning function activation command triggered when the vehicle is parked and in neutral, the hybrid transmission controller sends an over-authority control request to the vehicle controller. Upon receiving permission from the vehicle controller to override control, the hybrid transmission controller takes over control of the engine controller and the motor controller from the vehicle controller. The hybrid transmission controller sends a target torque command for the motor to the motor controller; The motor controller controls the motor to start and controls the motor to output torque according to the target torque command. The motor starts the engine through the clutch.

[0015] S2, after the engine starts, a clutch disengagement command is sent to disengage the clutch and cut off the power transmission between the engine and the motor.

[0016] S3, after the clutch disengages, the speed of the motor is controlled to be stabilized at the target speed of the motor, and the speed of the engine is controlled to be stabilized at the target speed of the engine, so as to provide a stable reference environment for torque measurement during the subsequent clutch engagement process.

[0017] In this embodiment of the invention, step S3 includes: The hybrid transmission controller continuously sends the target speed and motor speed control command to the motor controller. After receiving the target speed and motor speed control command, the motor controller adjusts the motor torque according to the difference between the actual speed and the target speed. When the target speed and the actual speed are the same, the motor torque remains unchanged. The hybrid transmission controller continuously sends the engine's target speed and engine speed control commands to the engine controller to control the engine speed and keep the engine stable at the target speed.

[0018] In a preferred embodiment of the present invention, to prevent the engine from stalling in subsequent steps, the target speed of the motor is set to the engine's idle speed. To ensure that the engine can provide sufficient torque in subsequent steps, the target speed of the engine is set to the maximum torque speed point.

[0019] S4, control the clutch to engage. During clutch engagement, maintain the engine speed at the target engine speed and acquire the motor angular acceleration, motor torque, motor moment of inertia, and clutch displacement in real time. Calculate the torque transmitted by the clutch based on the motor angular acceleration, motor torque, and motor moment of inertia. By maintaining a stable engine speed, the relationship between motor parameter changes and clutch torque can be analyzed more clearly. Precise calculations of parameters such as motor angular acceleration, torque, and moment of inertia accurately reflect the magnitude of the torque transmitted by the clutch at different positions, providing crucial data for forming an accurate clutch torque curve.

[0020] In a preferred embodiment of the present invention, the real-time acquisition of motor angular acceleration, motor torque, motor moment of inertia, and clutch displacement, and the acquisition of the torque transmitted by the clutch based on the motor angular acceleration, the motor torque, and the motor moment of inertia, includes: The hybrid transmission controller (TCU) receives real-time feedback on the motor speed from the motor controller (MCU). and motor torque The hybrid transmission controller (TCU) receives the clutch displacement detected by the displacement sensor on the clutch actuator in real time.

[0021] The motor angular acceleration is calculated based on the motor speed, and the formula for obtaining the motor angular acceleration is as follows:

[0022] in, This refers to the angular acceleration of the motor. This refers to the change in motor speed; For time difference.

[0023] The torque transmitted by the clutch is obtained based on the motor's angular acceleration, moment of inertia, and torque. The formula for obtaining the torque transmitted by the clutch is as follows:

[0024] in, The torque transmitted by the clutch; This is the motor's torque at this moment; This represents the moment of inertia of the motor.

[0025] S5, after the motor torque reaches the set torque threshold, a clutch transmission torque curve is formed based on the clutch displacement and the torque transmitted by the clutch. The clutch transmission torque curve can intuitively show the relationship between the clutch transmitted torque and the clutch position, providing a basis for accurate clutch control during subsequent vehicle gear shifts.

[0026] In a preferred embodiment of the present invention, the set torque threshold is 80% of the maximum torque of the motor.

[0027] In a preferred embodiment of the present invention, the method further includes: after the motor torque reaches a set torque threshold, controlling the clutch to return to the closed state and controlling the engine to shut off. Controlling the clutch to return to the closed state and shutting off the engine completes the entire self-learning process, restoring the vehicle to normal operation.

[0028] In a preferred embodiment of the present invention, the method further includes: after the motor torque reaches a set torque threshold, the hybrid transmission controller TCU cancels the speed control of the engine controller ECU and the motor controller MCU, and the hybrid transmission controller TCU relinquishes its authority to the vehicle controller HCU.

[0029] This invention successfully solves the technical challenge of P2 hybrid commercial vehicles, where clutch torque transmission characteristics cannot be corrected like in traditional AMT commercial vehicles due to clutch non-slippage during pure electric start-up. Through specific self-learning methods and steps, it provides an effective clutch torque self-learning pathway for P2 hybrid commercial vehicles, filling a technological gap in this field. This invention can accurately calculate the torque transmitted by the clutch and form an accurate torque transmission curve, ensuring smooth power connection before and after gear shifts. During gear shifts, controlling the clutch according to the accurate torque transmission curve effectively avoids power interruption or shock, greatly improving driving comfort and making the driving process smoother and more natural. This invention adopts a vehicle-wide communication control method, achieving full automation of the entire self-learning process through communication between the hybrid transmission TCU, vehicle controller HCU, engine ECU, and motor MCU. This fully automated control method avoids the influence of human factors (including subjective judgment and objective operational errors) on the self-learning results, improving the accuracy and reliability of self-learning. Simultaneously, it reduces the driver's operational difficulty, eliminating the need for complex operations to trigger and complete the self-learning process; the driver only needs to manually activate the self-learning function when specific conditions are met, improving ease of use.

[0030] See Figure 2 Based on the above method, the present invention also discloses a system for self-learning clutch torque in a P2 hybrid commercial vehicle, comprising: The motor start control module is used to send a motor start command in response to the clutch torque self-learning function activation command triggered when the vehicle is in a parked and stationary state and the gear is in N gear. After the motor starts, the motor drives the engine to start through the clutch. The clutch disengagement control module is used to send a clutch disengagement command after the engine is started; The speed control module is used to control the speed of the motor to stabilize at the target speed of the motor after the clutch is disengaged, and to control the speed of the engine to stabilize at the target speed of the engine. The data acquisition module is used to control the clutch engagement. During the clutch engagement process, the engine speed is controlled to be maintained at the target engine speed, and the motor angular acceleration, motor torque, motor rotational inertia and clutch displacement are acquired in real time. The torque transmitted by the clutch is obtained based on the motor angular acceleration, the motor torque and the motor rotational inertia. The transmission twist line acquisition module is used to generate a clutch transmission twist line based on the clutch displacement and the torque transmitted by the clutch after the motor torque reaches a set torque threshold, control the clutch to return to the closed state, and control the engine to shut down.

[0031] The various modules of this invention work together to accurately calculate the torque transmitted by the clutch and form an accurate transmission torque curve, ensuring the smoothness of power connection before and after gear shifting and realizing full automation of the entire self-learning process.

[0032] Example 2: See Figure 1 The purpose of this invention is to propose a method for self-learning the clutch torque of a P2 hybrid commercial vehicle, in order to correct the torque transmission characteristics of the clutch of a P2 hybrid commercial vehicle and determine the correspondence between the clutch transmission torque and the clutch position.

[0033] S1, when the vehicle is parked and stationary, and the gear is N, the driver manually activates the clutch torque self-learning function.

[0034] Once this function is activated, the hybrid transmission controller (TCU) sends an unauthorized control command to the vehicle controller (HCU). After the vehicle controller (HCU) agrees to the unauthorized control, the hybrid transmission controller (TCU) takes over from the vehicle controller (HCU) to implement unauthorized control over the engine controller (ECU) and the motor controller (MCU).

[0035] The hybrid transmission controller (TCU) sends an engine start command to the engine controller (ECU), and the target torque for the electric motor is sent to the motor controller (MCU). The electric motor then starts the engine via the clutch.

[0036] S2, after the hybrid transmission controller TCU detects that the engine has started, it controls the clutch actuator to disengage the clutch.

[0037] S3, after the clutch disengages, the hybrid transmission controller (TCU) continuously sends the target motor speed and speed control commands to the motor controller (MCU) to control the motor speed and stabilize it at the target speed. The TCU also continuously sends the target engine speed and speed control commands to the engine controller (ECU) to control the engine speed and stabilize it at the target speed. To prevent the engine from stalling during subsequent operations, the target motor speed is set to the engine's idle speed; to ensure sufficient torque from the engine during subsequent operations, the target engine speed is set to the maximum torque speed.

[0038] Once the hybrid transmission controller (TCU) detects that both the engine and electric motor have reached their target speeds, it controls the clutch actuator to engage at a slower rate. As the clutch engages, its position changes, and the transmitted torque increases. Due to the speed difference between the engine and electric motor, some of the engine's torque is transmitted to the electric motor during clutch engagement, causing the electric motor speed to tend to increase and the engine speed to tend to decrease. The engine controller (ECU) and the electric motor controller (MCU) then adjust the engine torque and electric motor torque respectively to maintain the engine and electric motor at their respective target speeds.

[0039] S4. During clutch engagement, the hybrid transmission controller (TCU) receives motor speed and torque feedback from the motor controller (MCU). By combining the motor's moment of inertia, current torque, and current angular acceleration, the torque transmitted by the clutch at that moment can be calculated. As the clutch continues to engage, the clutch position and the calculated torque change continuously and correspond one-to-one, thus obtaining the relationship between different clutch positions and the torque transmitted by the clutch, i.e., the clutch torque curve.

[0040] S5: When the motor torque reaches 80% of its maximum torque, the clutch transmission torque curve learning is considered complete, and the resulting correspondence is stored in the hybrid transmission controller (TCU). The TCU then cancels speed control over the engine controller (ECU) and motor controller (MCU), returns the clutch to the closed state, and relinquishes its overriding authority to the vehicle controller (HCU). After the HCU reclaims its overriding authority, it returns to the state before self-learning. Upon receiving the engine shutdown command from the HCU, the engine controller (ECU) shuts down the engine.

[0041] Compared with the prior art, the present invention has the following technical effects: By having the driver manually activate the clutch torque curve self-learning function, the problem of P2 hybrid commercial vehicles lacking the traditional AMT torque curve self-learning opportunity can be solved. The torque transmitted by the clutch can be accurately calculated through the motor torque, motor rotational inertia and motor angular acceleration. The resulting torque curve ensures the smoothness of power connection before and after gear shifting and improves comfort.

[0042] This invention utilizes vehicle-wide communication control, specifically through communication between the hybrid transmission controller (TCU), vehicle controller (HCU), engine controller (ECU), and motor controller (MCU). The entire self-learning process is fully automated, avoiding the influence of subjective and objective human factors, improving the accuracy of self-learning, and reducing the difficulty of operation for the driver.

[0043] Example 3: like Figure 3As shown, the vehicle model to which the method of the present invention is applied is a hybrid P2 architecture AMT commercial vehicle. The AMT transmission and the motor are integrated into one assembly. The clutch driven plate is connected to one end of the motor, and the other end of the motor is connected to the input shaft of the AMT transmission.

[0044] like Figure 4 As shown, the vehicle controller (HCU), the hybrid transmission controller (TCU) of the hybrid AMT transmission, the engine controller (ECU), and the motor controller (MCU) are all nodes on the vehicle's CAN (Controller Area Network) bus network. Each node controls its respective subsystem by sending and receiving messages. If the hybrid transmission controller (TCU) needs to control the motor and engine, it first sends a request for unauthorized control to the vehicle controller (HCU). After the HCU grants permission, the hybrid transmission controller (TCU) sends commands to the engine controller (ECU) and the motor controller (MCU) to control the engine and motor.

[0045] like Figure 5 As shown, the present invention provides a method for self-learning clutch torque in a P2 hybrid commercial vehicle, comprising the following steps: Step 1: Start the engine. When the driver activates the clutch torque self-learning function, the hybrid transmission controller (TCU) sends an overriding request to the vehicle controller (HCU) to gain overriding control over the electric motor and engine. It then sends a start request to the engine controller (ECU) and torque control commands and target torque to the electric motor controller (MCU). At this time, the clutch is engaged, and the electric motor torque is transmitted through the clutch driven plate to the clutch pressure plate, and finally to the engine flywheel, starting the engine. After the engine has started, the hybrid transmission controller (TCU) stops torque control of the electric motor controller (MCU).

[0046] Step 2, disengage the clutch. After the engine starts, the hybrid transmission controller (TCU) controls the clutch actuator to disengage the clutch.

[0047] Step 3: Engine and Motor Speed ​​Control. The hybrid transmission controller (TCU) continuously sends the target motor speed and speed control commands to the motor controller (MCU). Upon receiving the target speed and speed control commands, the MCU adjusts the motor torque based on the difference between the actual and target speeds. The larger the difference, the greater the motor torque. When the target and actual speeds match, the motor torque remains constant, stabilizing the motor at the target speed. The hybrid transmission controller (TCU) also continuously sends the engine's target speed and speed control commands to the engine controller (ECU) to control the engine speed and stabilize it at the target speed. To prevent the engine from stalling in later steps, the target motor speed is set to the engine's idle speed; to ensure sufficient torque from the engine in later steps, the target engine speed is set to the maximum torque speed.

[0048] Step 4: The clutch engages slowly. During clutch engagement, the hybrid transmission controller (TCU) receives the motor speed feedback from the motor controller (MCU). and motor torque First, calculate the angular acceleration of the motor. Combined with the rotational inertia of the motor The motor's torque at this moment The torque transmitted by the clutch at this moment can be calculated. Meanwhile, the hybrid transmission control unit (TCU) also obtains the clutch displacement at this moment through the displacement sensor on the clutch actuator. As the clutch continuously closes, the clutch position and the calculated torque... These are constantly changing and correspond one-to-one, so the correspondence between different clutch positions and the torque transmitted by the clutch can be obtained, that is, the clutch torque curve.

[0049] Step 5: Torque self-learning complete. Once the motor torque reaches 80% of its maximum, the clutch transmission torque curve learning is considered complete, and the resulting correspondence is stored in the hybrid transmission controller (TCU). The TCU then cancels speed control over the engine controller (ECU) and motor controller (MCU), returning the clutch to the closed state. The TCU relinquishes its overstepping authority to the vehicle controller (HCU). After the HCU reclaims its overstepping authority, it returns to the state before self-learning. Upon receiving the shutdown command from the HCU, the engine controller (ECU) shuts down the engine.

[0050] like Figure 6As shown, after the engine starts, the actual clutch displacement percentage (TMd_PctgCluActrPosnAct) opens to approximately 45%, and the clutch disengages. Then, the speed regulation phase begins, with the motor speed (MotCurrSpd) reaching 700 rpm and the engine speed (TSI_NEngAct) reaching 1200 rpm. The clutch then slowly closes. Due to the different target speeds of the engine and motor, the engine speed decreases while the motor speed increases. To keep the actual speed near the target speed, the motor torque (MotCurrTq) (negative values ​​indicate the direction) also continuously increases. The learning process is considered complete when the motor torque (MotCurrTq) reaches 220 Nm. This learning is repeated three times to obtain a more accurate clutch torque curve. Figure 7 As shown, this is the torque transmission characteristic of the clutch before and after self-learning. The left side is before learning, and the right side is after learning. Figure 7 The top 7 rows show the torque that the clutch can transmit, and the bottom 7 rows show the corresponding clutch displacement.

[0051] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of this invention.

Claims

1. A method for self-learning clutch torque in a P2 hybrid commercial vehicle, characterized in that, Includes the following steps: In response to the clutch torque self-learning function activation command triggered when the vehicle is parked and stationary and the gear is in N, a motor start command is sent, and after the motor starts, the motor drives the engine to start through the clutch. After the engine starts, a clutch disengagement command is sent; After the clutch disengages, the speed of the motor is controlled to be stabilized at the target speed of the motor, and the speed of the engine is controlled to be stabilized at the target speed of the engine. The clutch is controlled to close. During the clutch closure process, the engine speed is controlled to be maintained at the target engine speed, and the motor angular acceleration, motor torque, motor rotational inertia and clutch displacement are acquired in real time. The torque transmitted by the clutch is obtained based on the motor angular acceleration, the motor torque and the motor rotational inertia. After the motor torque reaches the set torque threshold, a clutch transmission twist line is formed based on the clutch displacement and the torque transmitted by the clutch.

2. The method for self-learning clutch torque in a P2 hybrid commercial vehicle according to claim 1, characterized in that, In response to a clutch torque self-learning function activation command triggered when the vehicle is parked and in neutral (N) gear, a motor start command is sent. After the motor starts, the motor drives the engine to start via the clutch, including: In response to the clutch torque self-learning function activation command triggered when the vehicle is parked and in neutral, the hybrid transmission controller sends an over-authority control request to the vehicle controller. Upon receiving permission from the vehicle controller to override control, the hybrid transmission controller takes over control of the engine controller and the motor controller from the vehicle controller. The hybrid transmission controller sends a target torque command for the motor to the motor controller; The motor controller controls the motor to start and controls the motor to output torque according to the target torque command. The motor starts the engine through the clutch.

3. The method for self-learning clutch torque in a P2 hybrid commercial vehicle according to claim 2, characterized in that, After the clutch disengages, controlling the motor speed to stabilize at the target motor speed and controlling the engine speed to stabilize at the target engine speed includes: The hybrid transmission controller continuously sends the target speed and motor speed control command to the motor controller. After receiving the target speed and motor speed control command, the motor controller adjusts the motor torque according to the difference between the actual speed and the target speed. When the target speed and the actual speed are the same, the motor torque remains unchanged. The hybrid transmission controller continuously sends the engine's target speed and engine speed control commands to the engine controller to control the engine speed and keep the engine stable at the target speed.

4. The method for self-learning clutch torque in a P2 hybrid commercial vehicle according to claim 1, characterized in that, The target speed of the motor is set to the idle speed of the engine, and the target speed of the engine is set to the maximum torque speed point.

5. The method for self-learning clutch torque in a P2 hybrid commercial vehicle according to claim 1, characterized in that, The real-time acquisition of motor angular acceleration, motor torque, motor moment of inertia, and clutch displacement, and the acquisition of the torque transmitted by the clutch based on the motor angular acceleration, motor torque, and motor moment of inertia, includes: The hybrid transmission controller (TCU) receives real-time feedback on the motor speed from the motor controller (MCU). and motor torque The hybrid transmission controller (TCU) receives the clutch displacement detected by the displacement sensor on the clutch actuator in real time. Calculate the motor angular acceleration based on the motor speed; The torque transmitted by the clutch is obtained based on the motor's angular acceleration, moment of inertia, and torque.

6. The method for self-learning clutch torque in a P2 hybrid commercial vehicle according to claim 5, characterized in that, The formula for obtaining the motor angular acceleration is as follows: in, This refers to the angular acceleration of the motor. This refers to the change in motor speed; For time difference; The formula for obtaining the torque transmitted by the clutch is as follows: in, The torque transmitted by the clutch; This is the motor's torque at this moment; This represents the moment of inertia of the motor.

7. The method for self-learning clutch torque in a P2 hybrid commercial vehicle according to claim 1, characterized in that, The set torque threshold is 80% of the motor's maximum torque.

8. The method for self-learning clutch torque in a P2 hybrid commercial vehicle according to claim 1, characterized in that, Also includes: After the motor torque reaches the set torque threshold, the clutch is controlled to return to the closed state, and the engine is shut off.

9. A method for self-learning clutch torque in a P2 hybrid commercial vehicle according to claim 2, characterized in that, Also includes: After the motor torque reaches the set torque threshold, the hybrid transmission controller TCU cancels the speed control of the engine controller ECU and the motor controller MCU, and the hybrid transmission controller TCU relinquishes its authority to the vehicle controller HCU.

10. A system for self-learning clutch torque in a P2 hybrid commercial vehicle, characterized in that, include: The motor start control module is used to send a motor start command in response to the clutch torque self-learning function activation command triggered when the vehicle is in a parked and stationary state and the gear is in N gear. After the motor starts, the motor drives the engine to start through the clutch. The clutch disengagement control module is used to send a clutch disengagement command after the engine is started; The speed control module is used to control the speed of the motor to stabilize at the target speed of the motor after the clutch is disengaged, and to control the speed of the engine to stabilize at the target speed of the engine. The data acquisition module is used to control the clutch engagement. During the clutch engagement process, the engine speed is controlled to be maintained at the target engine speed, and the motor angular acceleration, motor torque, motor rotational inertia and clutch displacement are acquired in real time. The torque transmitted by the clutch is obtained based on the motor angular acceleration, the motor torque and the motor rotational inertia. The transmission twist line acquisition module is used to form a clutch transmission twist line based on the clutch displacement and the torque transmitted by the clutch after the motor torque reaches a set torque threshold.

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