Hybrid amt shift control method and system

Abstract

This invention discloses a hybrid AMT (Automated Manual Transmission) shift control method and system, relating to the field of vehicle shifting technology. The method includes: determining whether the transmission meets shifting conditions based on driving information; determining a target gear value based on the current vehicle state; gradually reducing the power source output torque based on the target gear value; performing a disengagement operation via an actuator; adjusting the motor speed based on the actuator's speed difference; controlling the transmission to engage a gear based on the target gear value; and gradually restoring the power source output torque based on the target torque value. According to the technical solution of this application, high-precision control of the motor speed in commercial vehicles can be achieved, effectively improving the shifting success rate of hybrid AMT systems and possessing high application value.

Description

Technical Field

[0001] This invention relates to the field of vehicle shifting technology, and in particular to a hybrid AMT shifting control method and system. Background Technology

[0002] Commercial vehicles, as a means of production, drive economic development. However, due to their complex usage scenarios, safety accidents are frequent, making improved safety a major challenge in commercial vehicle manufacturing. Hybrid AMT systems, as one of the main control systems in commercial vehicles, are crucial to their safety performance. Traditional hybrid AMT systems adjust speed through clutches and brakes during gear shifts. This method suffers from poor motor speed control response, resulting in long shift times and even shift failures due to actuator speed differences exceeding reasonable ranges. Therefore, the development of a simple and efficient method to improve the shift success rate of hybrid AMT systems is urgently needed.

[0003] Most existing methods for improving the shift success rate of hybrid AMT systems have certain shortcomings. For example, patent application CN105197006A discloses a pure electric drive start-up control method for hybrid vehicles. This method controls the drive motor to perform closed-loop speed control during vehicle start-up, requiring the drive motor speed to be maintained at a target speed. It also controls the clutch in the transmission to engage slowly, allowing the drive motor to control the vehicle's slow start-up through the transmission. When shifting gears, the drive motor is controlled to exit the closed-loop speed control to achieve torque control. The torque executed by the drive motor is the sum of the actual torque of the drive motor and the torque required by the driver. However, this method often fails to provide sufficient acceleration torque when facing steep inclines, and its shift strategy based on speed and throttle input cannot meet the demands of complex operating conditions. Therefore, based on this problem, this application proposes a hybrid AMT shift control method and system. Summary of the Invention

[0004] Technical Purpose

[0005] To address the aforementioned issues, the present invention aims to provide a hybrid AMT shift control method and system that achieves high-precision control of the motor speed in commercial vehicles, effectively improving the shift success rate of hybrid AMT systems. This method and system have a wide range of applications. By optimizing the control method during the shift process of the AMT system, the response time of motor speed regulation is shortened, thereby improving the shift success rate of the AMT system.

[0006] Technical solution

[0007] To achieve the above objectives, the present invention provides a hybrid AMT shift control method and system, which determines the vehicle's shift requirements based on driving information and vehicle status, determines the target gear value by accurately calculating the vehicle's current acceleration, compensates for the reduced output torque during shifting, and achieves synchronous control of engine speed and clutch speed after shifting, thereby realizing smooth torque control during vehicle shifting and effectively improving the shift success rate of the hybrid AMT system.

[0008] In a first aspect, the present invention provides a hybrid powertrain AMT shift control method, comprising:

[0009] Determine whether the transmission meets the shifting conditions based on driving information;

[0010] Determine the target gear value based on the current vehicle status;

[0011] Gradually reduce the output torque of the power source according to the target gear value;

[0012] The file removal operation is performed using an actuator;

[0013] Adjust the motor speed according to the speed difference of the actuator;

[0014] The transmission is controlled to engage gears based on the target gear value;

[0015] The power source output torque is gradually restored according to the target torque value.

[0016] Furthermore, the transmission's shift conditions include vehicle speed, engine speed, and throttle opening; the vehicle's acceleration is calculated based on the throttle opening and the mapping relationship between the maximum torque output in each gear range and the engine speed, and the target gear value is determined based on the vehicle speed, vehicle acceleration, and a preset acceleration threshold.

[0017] Furthermore, before reducing the output torque of the power source, the method outputs the shifting demand of the transmission to the control module to determine the shifting demand; the control module determines whether the shifting demand needs to be met based on the current mode of the vehicle and whether it is performing energy recovery.

[0018] Furthermore, if the control module determines that the current moment is not the optimal time to shift gears when evaluating the shift request, the control module will reject the shift request.

[0019] Furthermore, after the control module approves this shift request, the transmission will issue instructions to the power source to gradually reduce its output torque until the torque is 0; the power source includes the electric motor and the engine.

[0020] Furthermore, when the output torque of the power source drops to 0, the transmission controls the gearbox actuator to perform a disengagement operation, that is, to disengage the current gear.

[0021] Furthermore, once the transmission successfully shifts into neutral, it requests control of the motor speed to keep the speed difference of the actuator within a reasonable range.

[0022] Furthermore, the target speed for motor adjustment is determined based on the vehicle's current gear, target gear, vehicle speed, and input speed.

[0023] Furthermore, once the speed difference between the actuators remains within a reasonable range, the transmission performs the gear shifting operation.

[0024] Furthermore, the gear shifting steps of the transmission include synchronization, synchronization in progress, locking initiation, and locking completion. Synchronization refers to gear engagement preparation, locking initiation refers to gear engagement, and locking completion refers to gear full engagement. Before the transmission's synchronization engagement mechanism is disconnected from its corresponding gear, the hybrid AMT shift control method achieves torque compensation through torque transfer.

[0025] Furthermore, once the system confirms that the transmission is in gear, the transmission control power source gradually restores its output torque until the torque reaches the target torque value set by the control module.

[0026] Furthermore, torque smoothness control is implemented during vehicle gear shifts, including compensating for reduced output torque during gear shifts and synchronizing engine speed and clutch speed after gear shifts.

[0027] Furthermore, the method also includes a coordinated control method for regenerative braking and mechanical braking, which dynamically allocates the ratio of regenerative braking and mechanical braking according to braking demand and battery status, and adjusts the force of regenerative braking and mechanical braking by coordinating the control of the engine, motor, clutch and transmission during gear shifting.

[0028] Furthermore, the method also includes a self-learning method for the deviation between the clutch and the shift position, which learns the actual positional deviation of the clutch and the shift mechanism to compensate for manufacturing errors and wear.

[0029] In a second aspect, the present invention also provides a hybrid AMT shift control system, the system being based on the method described in the first aspect above, comprising:

[0030] The data acquisition module is used to collect vehicle driving information;

[0031] The calculation module is used to calculate the vehicle's current acceleration;

[0032] A torque compensation module is used to compensate for torque reduction.

[0033] The control module is used to determine shifting needs and manage and distribute torque;

[0034] The execution module is used to execute the instruction signals of the control module.

[0035] Furthermore, vehicle driving information includes the maximum output torque of the engine and drive motor, throttle opening, wheel speed, etc.

[0036] Furthermore, the execution module includes a transmission, gearbox, etc.; the transmission includes a main shaft, a driven shaft, a drive shaft, multiple synchronous meshing mechanisms, and multiple gears. The main shaft is contained inside the driven shaft, and the main shaft and the driven shaft rotate independently. The drive shaft is arranged parallel to the main shaft and the driven shaft. The gears arranged on the drive shaft and the gears arranged on the main shaft and the driven shaft are always in a meshing state, so that each shaft is connected by transmission through the multiple synchronous meshing mechanisms and the multiple gears.

[0037] Thirdly, the present invention also provides a computer device, including a processor and a memory, the processor being connected to the memory, the memory being used to store a computer program, and the processor being used to execute the computer program stored in the memory, so that the computer device performs the aforementioned hybrid AMT shift control method.

[0038] Fourthly, the present invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the aforementioned hybrid AMT shift control method.

[0039] This invention determines the vehicle's shifting requirements based on driving information and vehicle status. It determines the target gear value by accurately calculating the vehicle's current acceleration. By compensating for the reduced output torque during shifting and synchronously controlling engine and clutch speeds after shifting, it achieves smooth torque control during gear shifts. It dynamically allocates the ratio of regenerative braking to mechanical braking based on braking demand and battery status. During shifting, it coordinates the control of the engine, motor, clutch, and transmission to adjust the intensity of regenerative and mechanical braking. It also compensates for manufacturing errors and wear by learning the actual positional deviations of the clutch and shifting mechanism. This method and system achieve high-precision control of the commercial vehicle's motor speed, effectively improving the shifting success rate of hybrid AMT systems. The method and system have wide applications. By optimizing the control method during AMT system shifting, it shortens the motor speed adjustment response time and improves the shifting success rate of the AMT system.

[0040] Beneficial effects

[0041] By implementing the hybrid AMT shift control method and system provided by the present invention, the following technical effects are achieved:

[0042] (1) The vehicle's shifting requirements are determined based on driving information and vehicle status. The target gear value of the vehicle is determined by accurately calculating the current acceleration of the vehicle. This shortens the response time of motor speed regulation, improves the shifting success rate of the AMT system, reduces vehicle speed oscillation during shifting, improves the smoothness of shifting, and achieves optimal power output.

[0043] (2) By compensating for the reduced output torque during gear shifting and synchronizing the engine speed and clutch speed after gear shifting, the smoothness control of torque during gear shifting is achieved; it avoids power interruption during gear shifting, improves the smoothness of gear shifting and driving comfort; reduces shock and vibration during gear shifting, improves gear shifting quality; reduces energy loss during gear shifting, and improves the fuel economy of the whole vehicle.

[0044] (3) The ratio of regenerative braking and mechanical braking is dynamically allocated according to braking demand and battery status. During gear shifting, the engine, motor, clutch and transmission are coordinated and controlled to adjust the force of regenerative braking and mechanical braking. It converts the kinetic energy of the vehicle during braking into electrical energy, which improves the energy utilization rate. By precisely controlling the intervention mode of regenerative braking and mechanical braking, the impact and vibration during braking are reduced, and the power performance of the vehicle is improved.

[0045] (4) By learning the actual position deviation of the clutch and shifting mechanism to compensate for manufacturing errors and wear, the accuracy of shifting is improved; by self-learning the key positions of the clutch and shifting mechanism, the stability of the AMT system is guaranteed; the power interruption and shock during the shifting process are reduced, and the smoothness of the shifting process is further improved. Attached Figure Description

[0046] To make the above-described hybrid AMT shift control method and system of the present invention more obvious and understandable, the accompanying drawings used in the specific embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0047] Figure 1 This diagram illustrates the shift control method for a hybrid AMT (Automated Manual Transmission) system.

[0048] Figure 2 This diagram illustrates the shift control process of a hybrid AMT (Automated Manual Transmission). Detailed Implementation

[0049] Example 1:

[0050] A hybrid AMT shift control method is provided, the shift control method is as follows: Figure 1 As shown, the shift control process is as follows: Figure 2 As shown, the method includes:

[0051] Determine whether the transmission meets the shifting conditions based on driving information;

[0052] Determine the target gear value based on the current vehicle status;

[0053] Gradually reduce the output torque of the power source according to the target gear value;

[0054] The file removal operation is performed using an actuator;

[0055] Adjust the motor speed according to the speed difference of the actuator;

[0056] The transmission is controlled to engage gears based on the target gear value;

[0057] The power source output torque is gradually restored according to the target torque value.

[0058] The shift conditions of the transmission include vehicle speed, engine speed, and throttle opening. The vehicle acceleration is calculated based on the throttle opening and the mapping relationship between the maximum torque output in each gear range and the engine speed. The target gear value is determined based on the vehicle speed, vehicle acceleration, and a preset acceleration threshold.

[0059] Before reducing the output torque of the power source, the method outputs the shift demand of the transmission to the control module to determine the shift demand; the control module determines whether the shift demand needs to be met based on the current mode of the vehicle and whether it is performing energy recovery.

[0060] If the control module determines that the current moment is not the optimal time to shift gears when evaluating the shift request, the control module will reject the shift request.

[0061] After the control module approves the shift request, the transmission will issue a command to the power source to gradually reduce its output torque until the torque is 0; the power source includes the electric motor and the engine.

[0062] When the output torque of the power source drops to 0, the transmission controls the gearbox actuator to perform a disengagement operation, that is, to disengage the current gear.

[0063] Once the transmission successfully shifts into neutral, it requests control of the motor speed to keep the speed difference of the actuator within a reasonable range.

[0064] The target speed for motor adjustment is determined based on the vehicle's current gear, target gear, vehicle speed, and input speed.

[0065] Once the speed difference between the actuators remains within a reasonable range, the transmission engages the gear.

[0066] The steps for shifting gears in the transmission include synchronization, synchronization in progress, locking initiation, and locking completion. Synchronization refers to gear engagement preparation, locking initiation refers to gear engagement, and locking completion refers to gear full engagement. Before the transmission's synchronization engagement mechanism is disconnected from its corresponding gear, the hybrid AMT shift control method achieves torque compensation through torque transfer.

[0067] Once the system confirms that the transmission is in gear, the transmission control power source gradually restores its output torque until the torque reaches the target torque value set by the control module.

[0068] Smooth torque control during vehicle gear shifts includes compensating for reduced output torque during shifts and synchronizing engine and clutch speeds after shifts.

[0069] The method also includes a coordinated control approach for regenerative braking and mechanical braking. This approach dynamically allocates the ratio of regenerative braking to mechanical braking based on braking demand and battery status. During gear shifting, it coordinates the control of the engine, motor, clutch, and transmission to adjust the intensity of regenerative and mechanical braking. Specifically, this includes: establishing a dynamic model of the hybrid vehicle to simulate its driving characteristics under different operating conditions; designing a shifting strategy based on the vehicle's driving state, considering both smooth shifting and maximizing energy recovery efficiency; during regenerative braking, rationally allocating the regenerative braking force from the motor and the mechanical braking force to ensure maximum energy recovery while meeting braking performance requirements; and using a coordinated control strategy for regenerative and mechanical braking to ensure vehicle braking stability and energy recovery efficiency under different road conditions. The application of this coordinated control method for regenerative and mechanical braking can improve the energy recovery efficiency of the hybrid AMT shifting control method by approximately 3%.

[0070] Example 2:

[0071] Based on the aforementioned embodiments, the method adds a self-learning method for the deviation between the clutch and the shifting position, which learns the actual positional deviation between the clutch and the shifting mechanism to compensate for manufacturing errors and wear;

[0072] First, the clutch's key positions need to be self-learned, including the positions of the disengagement point, engagement point, and slip point. The self-learning process is represented by the following formula:

[0073]

[0074] In the formula, This refers to the clutch torque; The target torque; The target rotational speed; Current rotational speed; This is a coefficient adjusted based on wear conditions.

[0075] The self-learning process of the transmission involves the precise position of the gear. Its self-learning control method includes: ensuring that the engine speed is within ±100 rpm of the target value of the control module when in P or N gear; ensuring that the engine torque is within ±4 Nm of the target value of the control module when in P or N gear; and ensuring that the engine temperature is above 60°C and the transmission temperature is between 20°C and 60°C.

[0076] During gear shifting, the coordinated control of the engine, electric motor, clutch, and transmission reduces power interruption time and shift shock, thereby improving shift quality. The control strategy is expressed by the following formula:

[0077]

[0078] In the formula, The total cost function; The cost function for tracking error; The cost function for controlling energy; The cost function for driving comfort; , and These are the weighting coefficients.

[0079] The model predictive control strategy, based on the vehicle's dynamics model, predicts the dynamic response during clutch engagement and adjusts control parameters in real time to achieve smooth gear shifting. The predictive model is expressed by the following formula:

[0080]

[0081] in, For the first The output increment of the step; These are model parameters; For the first Step control increment; This represents the bias term of the prediction model; To control the time domain.

[0082] By precisely controlling the shift actuator to adapt to changes in different driving conditions and vehicle states, the adaptive PID control method is expressed by the following formula:

[0083]

[0084] In the formula, For control input; For proportional gain; For error; For integral gain; This is the differential gain; Gain adjusted according to frequency response; This is the system frequency response function.

[0085] For example, suppose the vehicle's current speed is 50 km / h, the engine speed is 1000 rpm, and the electric motor speed is 0 rpm, and the vehicle needs to be shifted from 2nd gear to 3rd gear.

[0086] Assumption , , , ;

[0087]

[0088] Learn the gear position by following these steps: In P or N gear, ensure the engine speed is within ±100 rpm of the control module's target value; in P or N gear, ensure the engine torque is within ±4 Nm of the control module's target value.

[0089] Assumption , , The target speed is 60 km / h.

[0090]

[0091]

[0092]

[0093]

[0094] Assumption , , , , , , :

[0095] Assume the three future time steps are: , , ;

[0096]

[0097]

[0098]

[0099] Assumption , , , , , :

[0100]

[0101] The effectiveness of the self-learning method for the deviation between the clutch and the shift position is shown in Table 1:

[0102] Table 1. Summary of the effectiveness of the self-learning method for the deviation between the clutch and the shift position.

[0103] index Before applying the method After applying the method Improvement rate of effect Shift time (s) 0.8 0.6 25% Shift smoothness (unit) 3.5 1.2 64.3% Fuel efficiency (L / 100km) 5.8 5.5 5.2% Response time (ms) 500 300 40%

[0104] As shown in Table 1, the hybrid AMT method optimized by the clutch and shift position deviation self-learning method significantly reduces shift time, greatly improves shift smoothness, reduces fuel consumption per 100 kilometers from 5.8 to 5.5 liters, and reduces system response time by 200 milliseconds. This indicates that the clutch and shift position deviation self-learning method can effectively improve the performance of the hybrid AMT system, especially in terms of shift smoothness and shift time.

[0105] Example 3:

[0106] Based on the foregoing embodiments, a hybrid AMT shift control system is provided, specifically including:

[0107] The data acquisition module is used to collect vehicle driving information;

[0108] The calculation module is used to calculate the vehicle's current acceleration;

[0109] A torque compensation module is used to compensate for torque reduction.

[0110] The control module is used to determine shifting needs and manage and distribute torque;

[0111] The execution module is used to execute the instruction signals of the control module.

[0112] Vehicle driving information includes the maximum output torque of the engine and drive motor, throttle opening, wheel speed, etc.

[0113] The execution module includes a transmission, gearbox, etc.; the transmission includes a main shaft, a driven shaft, a drive shaft, multiple synchronous meshing mechanisms, and multiple gears. The main shaft is contained inside the driven shaft and the main shaft and the driven shaft rotate independently. The drive shaft is arranged parallel to the main shaft and the driven shaft. The gears arranged on the drive shaft and the gears arranged on the main shaft and the driven shaft are always in a meshing state, so that each shaft is connected by transmission through the multiple synchronous meshing mechanisms and the multiple gears.

[0114] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable non-transitory storage media containing computer-usable program code.

[0115] The present invention can provide computer program instructions to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, such that the instructions, which are executed by the processor of the computer or other programmable data processing device, produce means for implementing the system.

[0116] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means that perform the functions of the system.

[0117] These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, such that the instructions, which execute on the computer or other programmable apparatus, provide steps for implementing the functions of the system.

Claims

1. A hybrid AMT shift control method, characterized in that: include: Determine whether the transmission meets the shifting conditions based on driving information; Determine the target gear value based on the current vehicle status; Gradually reduce the output torque of the power source according to the target gear value; The file removal operation is performed using an actuator; Adjust the motor speed according to the speed difference of the actuator; The transmission is controlled to engage gears based on the target gear value; Gradually restore the power source output torque according to the target torque value; The method also includes a coordinated control method for regenerative braking and mechanical braking, and a self-learning method for the deviation between the clutch and shift positions. The self-learning method for the clutch and shift positions includes: self-learning the positions of the clutch disengagement point, engagement point, and slip point; the self-learning process requires that the engine temperature be above 60℃, the transmission temperature be between 20℃ and 60℃, and in P or N gear, the engine speed be maintained within ±100 rpm of the control module's target value, and the torque be maintained within ±4 Nm of the control module's target value; an adaptive PID control strategy based on frequency response-driven dynamic gain adjustment is used to achieve position deviation compensation.

2. The method according to claim 1, characterized in that: The shift conditions of the transmission include vehicle speed, engine speed, and throttle opening. The vehicle acceleration is calculated based on the throttle opening and the mapping relationship between the maximum torque output in each gear range and the engine speed. The target gear value is determined based on the vehicle speed, vehicle acceleration, and a preset acceleration threshold.

3. The method according to claim 1, characterized in that: Before reducing the output torque of the power source, the method outputs the shift demand of the transmission to the control module to determine the shift demand; the control module determines whether the shift demand needs to be met based on the current mode of the vehicle and whether it is performing energy recovery.

4. The method according to claim 3, characterized in that: Smooth torque control during vehicle gear shifts includes compensating for reduced output torque during shifts and synchronizing engine and clutch speeds after shifts.

5. The method according to claim 4, characterized in that: The steps for the transmission to engage gears include synchronization, synchronization in progress, locking at the start, and locking at the end; before the transmission's synchronizing engagement mechanism is disconnected from its corresponding gear, the hybrid AMT shift control method achieves torque compensation through torque transfer.

6. The method according to claim 1, characterized in that: The coordinated control method for regenerative braking and mechanical braking specifically includes: dynamically allocating the ratio of regenerative braking and mechanical braking according to braking demand and battery status, and adjusting the intensity of regenerative braking and mechanical braking by coordinating the control of the engine, motor, clutch and transmission during gear shifting.

7. The method according to claim 1, characterized in that: The self-learning method for the deviation between the clutch and the shifting position specifically includes: learning the actual positional deviation between the clutch and the shifting mechanism to compensate for manufacturing errors and wear.

8. A hybrid AMT shift control system, characterized in that: The system is implemented based on the method described in any one of claims 1-7: The system includes: The data acquisition module is used to collect vehicle driving information; The calculation module is used to calculate the vehicle's current acceleration; A torque compensation module is used to compensate for torque reduction. The control module is used to determine shifting needs and manage and distribute torque; The execution module is used to execute the instruction signals of the control module.

9. A computer device comprising a processor and a memory, the processor being connected to the memory, the memory being used to store computer programs, characterized in that: The processor is configured to execute a computer program stored in the memory, so that the computer device performs the method as described in any one of claims 1-7.

10. A computer-readable storage medium storing a computer program, characterized in that: The computer program is executed to implement the method according to any one of claims 1-7.

Images