AMT gear shifting control method of electric agricultural machine

Abstract

The present application relates to electric agricultural machine gear shifting control technical field, specifically disclose a kind of AMT gear shifting control method of electric agricultural machine, comprising: first, the current speed of electric agricultural machine, the output torque of the drive motor of electric agricultural machine is obtained, the whole vehicle resistance moment of electric agricultural machine is calculated, and the friction resistance moment that the meshing tooth in AMT gearbox is subjected is adjusted to preset value, subsequently can complete the action of taking off gear;After completing the action of taking off gear, the current speed of electric agricultural machine is obtained again, the output torque of drive motor, and the whole vehicle resistance moment of electric agricultural machine is calculated again, then the target speed of the drive motor of electric agricultural machine is calculated, and the difference between the current speed and target speed of the drive motor of electric agricultural machine is controlled to be less than 50rpm, to facilitate the drive motor of electric agricultural machine to complete the work of successfully completing gear engagement.This application effectively solves the problem of low gear shifting success rate and high speed regulation energy consumption in the prior art of electric agricultural machine AMT gear shifting control method.

Description

Technical Field

[0001] This invention relates to the field of electric agricultural machinery shift control technology, and in particular to an AMT shift control method for electric agricultural machinery. Background Technology

[0002] With the advancement of agricultural modernization, electric tractors are gradually gaining attention due to their advantages such as environmental friendliness, low noise, and high efficiency. However, because electric tractors have a large load, the power in existing electric tractor AMT (Automated Manual Transmission) systems disappears instantly during gear shifts, while torque changes take time, and there are potential issues such as overshoot leading to reverse torque. This results in difficulty disengaging gears, leading to low shift success rates and high energy consumption during speed regulation. Summary of the Invention

[0003] The purpose of this invention is to provide an AMT shift control method for electric agricultural machinery, so as to solve the problems of low shift success rate and high energy consumption for speed regulation in the existing AMT shift control methods for electric agricultural machinery.

[0004] To address the aforementioned problems, this invention provides an AMT (Automated Manual Transmission) shifting control method for electric agricultural machinery, comprising: S1: Responding to the driver's gear shifting command, obtain the current speed of the electric agricultural machinery and the output torque of the drive motor of the electric agricultural machinery; S2: Calculate the overall resistance torque of the electric agricultural machinery and adjust the frictional resistance torque on the meshing teeth of the AMT gearbox to a preset value; S3: The electric agricultural machinery completes the disengagement action; S4: After completing the disengagement action, obtain the current speed of the electric agricultural machinery and the output torque of the drive motor of the electric agricultural machinery again, and calculate the overall resistance torque of the electric agricultural machinery again. S5: Calculate the target speed of the drive motor of the electric agricultural machine, and control the difference between the current speed of the drive motor of the electric agricultural machine and the target speed to be less than 50 rpm; S6: The electric agricultural machinery completes the gear engagement action.

[0005] As an optional technical solution for AMT shift control of electric agricultural machinery, the method calculates the overall vehicle resistance torque of the electric agricultural machinery and adjusts the frictional resistance torque on the meshing teeth of the AMT gearbox to a preset value, including: ; Among them, F f The frictional resistance torque experienced by the meshing teeth within the AMT transmission. The coefficient of friction of the tooth surface. This refers to the gear ratio of the current electric agricultural machinery. It is the product of the transmission ratios of the central drive and the final drive of the electric agricultural machinery. The transmission system of the electric agricultural machinery is equivalent to the rotational inertia at the output end of the AMT gearbox. This is the equivalent torque inertia at the input end of the AMT transmission. The output torque of the drive motor is... The equivalent resistance torque of the electric agricultural machinery is... Let be the pitch circle radius of the AMT transmission coupling sleeve.

[0006] As an optional technical solution for AMT shift control methods in electric agricultural machinery, S2 also includes: By adjusting the output torque of the drive motor of the electric agricultural machinery in real time, the frictional resistance torque on the meshing teeth of the AMT gearbox reaches the preset value.

[0007] As an optional technical solution for the AMT shift control method of electric agricultural machinery, the AMT shift control method of the electric agricultural machinery further includes: After the electric agricultural machine completes the disengagement action, it determines whether the disengagement action was successful. If successful, it performs the engagement action; otherwise, it returns to S1.

[0008] As an optional technical solution for AMT shift control of electric agricultural machinery, the target speed of the drive motor of the electric agricultural machinery is calculated, including: The target rotational speed is calculated by the predictive controller using the MPC model.

[0009] As an optional technical solution for AMT shift control of electric agricultural machinery, controlling the difference between the current speed and the target speed of the drive motor of the electric agricultural machinery to be less than 50 rpm includes: After calculating the target rotational speed using the MPC model predictive controller, it is determined whether the electric agricultural machinery needs to increase its speed. If the electric agricultural machinery needs to increase its speed, the current speed of the drive motor of the electric agricultural machinery is controlled by fuzzy PID so that the difference between the current speed and the target speed is less than 50 rpm. If the electric agricultural machinery does not need to increase its speed, the energy recovery system of the electric agricultural machinery is activated, and the current speed of the drive motor of the electric agricultural machinery is controlled by the fuzzy PID control so that the difference between the current speed and the target speed is less than 50 rpm.

[0010] As an optional technical solution for AMT shift control in electric agricultural machinery, S5 also includes: Determine whether the difference between the current speed and the target speed is less than 50 rpm. If it is less than 50 rpm, then perform the gear shifting action; if it is greater than 50 rpm, then the target speed needs to be recalculated.

[0011] As an optional technical solution for the AMT shift control method of electric agricultural machinery, the AMT shift control method of the electric agricultural machinery further includes: After the electric agricultural machine completes the gear shifting action, it is determined whether the gear shifting action was successful. If successful, the gear shifting action of the electric agricultural machine is completed; if unsuccessful, it returns to S4.

[0012] As an optional technical solution for AMT shift control in electric agricultural machinery, S3 includes: The disengagement action is performed by the shift motor of the electric agricultural machinery.

[0013] As an optional technical solution for AMT shift control in electric agricultural machinery, S6 includes: The gear shifting action is performed by the gear shifting motor of the electric agricultural machinery.

[0014] The beneficial effects of this invention are as follows: This invention provides an AMT (Automated Manual Transmission) shifting control method for electric agricultural machinery. The method includes: performing a shifting operation based on the driver's shifting command; first, disengaging the gear; then, engaging the gear; and finally completing the shifting operation. Using this method, upon responding to the driver's shifting command, the current speed of the electric agricultural machinery and the output torque of its drive motor are first acquired. Then, the overall resistance torque of the electric agricultural machinery is calculated, and the frictional resistance torque on the meshing gears of the AMT gearbox is adjusted to a preset value. Disengaging the gear can then be completed. This setting reduces the difficulty and speeds up the disengaging process. After disengaging, the current speed and output torque of the drive motor are acquired again, and the overall resistance torque is calculated again. Then, the target speed of the drive motor is calculated, and the difference between the current speed and the target speed is controlled to be less than 50 rpm. This setting facilitates smooth gear engagement for the electric agricultural machinery. The AMT shift control method for electric agricultural machinery of the present invention effectively solves the problems of low shift success rate and high energy consumption for speed regulation in the existing AMT shift control methods for electric agricultural machinery. Attached Figure Description

[0015] Figure 1 This is a flowchart of the disengagement action of the AMT shift control method for electric agricultural machinery in an embodiment of the present invention; Figure 2This is a flowchart of the gear-shifting action of the AMT gear-shifting control method for electric agricultural machinery in an embodiment of the present invention. Detailed Implementation

[0016] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. 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.

[0017] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for 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 the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. The terms "first position" and "second position" refer to two different positions. Furthermore, "above," "on top of," and "over" the first feature in relation to the second feature includes the first feature directly above and diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "under," and "below" the first feature in relation to the second feature includes the first feature directly below and diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0018] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; 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; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0019] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0020] like Figures 1 to 2As shown, this embodiment provides an AMT (Automated Manual Transmission) shifting control method for an electric agricultural machine. The method includes: S1: Responding to the driver's shifting command, acquiring the current speed of the electric agricultural machine and the output torque of its drive motor; S2: Calculating the overall resistance torque of the electric agricultural machine and adjusting the frictional resistance torque on the meshing gears of the AMT transmission to a preset value; S3: The electric agricultural machine completes the disengagement action; S4: After completing the disengagement action, acquiring the current speed of the electric agricultural machine and the output torque of its drive motor again, and calculating the overall resistance torque of the electric agricultural machine again; S5: Calculating the target speed of the drive motor of the electric agricultural machine and controlling the difference between the current speed and the target speed of the drive motor to be less than 50 rpm; S6: The electric agricultural machine completes the engagement action.

[0021] The AMT (Automated Manual Transmission) shifting control method for electric agricultural machinery of the present invention, upon responding to the driver's shifting command, first acquires the current speed of the electric agricultural machinery and the output torque of the drive motor, then calculates the overall resistance torque of the electric agricultural machinery, and adjusts the frictional resistance torque on the meshing gears of the AMT gearbox to a preset value, thereby completing the disengagement action. This setting reduces the difficulty and speeds up the disengagement process. After disengaging, the current speed of the electric agricultural machinery and the output torque of the drive motor are acquired again, and the overall resistance torque of the electric agricultural machinery is calculated again. Then, the target speed of the drive motor is calculated, and the difference between the current speed and the target speed is controlled to be less than 50 rpm. This setting facilitates the smooth engagement of the electric agricultural machinery. The AMT shifting control method for electric agricultural machinery of the present invention effectively solves the problems of low shifting success rate and high energy consumption for speed regulation in existing AMT shifting control methods for electric agricultural machinery.

[0022] In this embodiment, calculating the overall resistance torque of the electric agricultural machinery and adjusting the frictional resistance torque on the meshing teeth of the AMT gearbox to a preset value includes: ; Among them, F f This refers to the frictional resistance torque experienced by the internal meshing teeth of the AMT transmission. The coefficient of friction of the tooth surface. This refers to the gear ratio of the current electric agricultural machinery. It is the product of the transmission ratios of the central drive and the final drive of the electric agricultural machinery. The transmission system of the electric agricultural machinery is equivalent to the rotational inertia at the output end of the AMT gearbox. This is the equivalent torque inertia at the input end of the AMT transmission. The output torque of the drive motor is... The equivalent resistance torque of the electric agricultural machinery is... Let be the pitch circle radius of the AMT transmission coupling sleeve.

[0023] From the above formula, we can see that F f The closer the torque is to 0, the less force is required for the disengagement action. When the output torque of the drive motor is 0, the disengagement action is the simplest. However, since torque change takes time and may cause reverse torque due to overshoot, the disengagement action becomes difficult. Therefore, in practice, the disengagement action can be initiated when the output torque of the drive motor is less than 20 Nm.

[0024] Specifically, S2 also includes: adjusting the output torque of the electric agricultural machinery's drive motor in real time to ensure that the frictional resistance torque on the meshing teeth of the AMT gearbox reaches a preset value. This allows for dynamic adjustment of the frictional resistance torque on the meshing teeth of the AMT gearbox based on the output torque of the drive motor, ensuring smooth disengagement.

[0025] In some embodiments, the AMT shift control method for electric agricultural machinery further includes: after the electric agricultural machinery completes the disengagement action, determining whether the disengagement action is successful; if successful, continuing the gear engagement action; if unsuccessful, returning to S1 to continue acquiring the current electric agricultural machinery speed, the output torque of the electric agricultural machinery's drive motor, and the overall vehicle resistance torque of the electric agricultural machinery.

[0026] Further, calculating the target speed of the electric agricultural machinery's drive motor includes: calculating the target speed using an MPC (Model Predictive Control) controller. MPC is an advanced control strategy based on the system's dynamic model. At each sampling time, it generates control commands by solving an open-loop optimal control problem within a finite time domain, and applies the first control action from the calculated optimal control sequence to the system, followed by rolling optimization and feedback correction. Its core feature is its ability to explicitly handle complex control problems with multiple variables and constraints, and to address model mismatch and external disturbances through online iterative optimization, thereby achieving high control accuracy and robustness. In this embodiment, the target speed is primarily calculated using an MPC model.

[0027] In some embodiments, controlling the difference between the current speed and the target speed of the electric agricultural machinery's drive motor to be less than 50 rpm includes: calculating the target speed using an MPC model predictive controller and determining whether the electric agricultural machinery needs to increase its speed; if the electric agricultural machinery needs to increase its speed, then controlling the current speed of the electric agricultural machinery's drive motor using fuzzy PID control to ensure that the difference between the current speed and the target speed is less than 50 rpm; if the electric agricultural machinery does not need to increase its speed, then activating the electric agricultural machinery's energy recovery system, and then controlling the current speed of the electric agricultural machinery's drive motor again using fuzzy PID control to ensure that the difference between the current speed and the target speed is less than 50 rpm. With this configuration, when the drive motor speed needs to be reduced, the energy recovery system is activated first; recovering electrical energy simultaneously achieves shock-free speed regulation and accelerates the deceleration process of the drive motor.

[0028] Furthermore, S5 also includes: determining whether the difference between the current speed of the drive motor of the electric agricultural machine and the target speed is less than 50 rpm. If it is less than 50 rpm, the gear shifting action continues; if it is greater than 50 rpm, the target speed needs to be recalculated.

[0029] It should be noted that in this application, the AMT shift control method for electric agricultural machinery has two adjustment modes during the gear shifting action. When in energy recovery mode, the trigger condition is that the speed of the electric agricultural machinery is greater than the target speed +50 rpm, and the control logic at this time is through fuzzy PID and energy recovery linkage. When in drive acceleration mode, the trigger condition is that the speed of the electric agricultural machinery is less than the target speed -50 rpm, and the control logic at this time is through fuzzy PID and positive compensation of the delivery torque of the drive motor.

[0030] In this embodiment, the AMT shift control method for electric agricultural machinery further includes: after the electric agricultural machinery completes the gear engagement action, determining whether the gear engagement action is successful; if successful, the shift action of the electric agricultural machinery is completed; if unsuccessful, returning to S4.

[0031] Furthermore, S3 includes: performing a disengagement action via the shift motor of the electric agricultural machinery. Similarly, S6 includes: performing a shift engagement action via the shift motor of the electric agricultural machinery.

[0032] A specific embodiment of the AMT shift control method for electric agricultural machinery using the present invention is as follows: Scenario: When the electric farm machinery is going uphill at a speed of 20km / h (8% gradient), the electric farm machinery shifts from 1st gear to 2nd gear.

[0033] Disengagement action: The calculated overall vehicle resistance torque is 185 N·m. Within 80 ms, the drive motor will reduce the output torque from the current value to 20 N·m (compensation amount 60 N·m). The shift motor will perform the disengagement action, causing the AMT transmission to shift from 1st gear to neutral.

[0034] Gear shifting action: Using the MPC model, the target speed required for shifting gears is calculated to be 3200 rpm based on the gear ratio of 2nd gear and the current vehicle speed. The current speed of the electric agricultural machinery's drive motor is detected to be 3350 rpm. It is determined that this is greater than the sum of the target speed and the allowable deviation of 50 rpm (i.e., 3200 rpm + 50 rpm = 3250 rpm), so the energy recovery system is activated. The current speed of the drive motor is controlled by fuzzy PID control. Within 0.5 seconds, the speed drops to 3180 rpm. At this time, the deviation between the current speed and the target speed is -20 rpm. The shift motor then performs the gear shifting action, completing the engagement of 2nd gear.

[0035] The advantages of the AMT shift control method for electric agricultural machinery of the present invention are as follows: 1. A central resistance torque calculation unit was established, which integrates information such as vehicle speed and drive motor output torque.

[0036] 2. The output parameters serve both torque compensation for disengaging gears and target speed calculation for engaging gears.

[0037] In the disengagement action, the external load is estimated in real time, and the output torque of the drive motor is dynamically adjusted to make the disengagement action easy; in the engagement action, the target speed that the drive motor needs to track is dynamically estimated by estimating the external load, and the drive motor speed is adjusted in real time to track a dynamically changing target speed.

[0038] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. An AMT (Automated Manual Transmission) shifting control method for electric agricultural machinery, characterized in that, include: S1: Responding to the driver's gear shifting command, obtain the current speed of the electric agricultural machinery and the output torque of the drive motor of the electric agricultural machinery; S2: Calculate the overall resistance torque of the electric agricultural machinery and adjust the frictional resistance torque on the meshing teeth of the AMT gearbox to a preset value; S3: The electric agricultural machinery completes the disengagement action; S4: After completing the disengagement action, obtain the current speed of the electric agricultural machinery and the output torque of the drive motor of the electric agricultural machinery again, and calculate the overall resistance torque of the electric agricultural machinery again. S5: Calculate the target speed of the drive motor of the electric agricultural machine, and control the difference between the current speed of the drive motor of the electric agricultural machine and the target speed to be less than 50 rpm; S6: The electric agricultural machinery completes the gear engagement action.

2. The AMT shifting control method for electric agricultural machinery according to claim 1, characterized in that, Calculating the overall resistance torque of the electric agricultural machinery and adjusting the frictional resistance torque on the meshing teeth of the AMT gearbox to a preset value includes: ； Among them, F f The frictional resistance torque experienced by the meshing teeth within the AMT transmission. The coefficient of friction of the tooth surface. This refers to the gear ratio of the current electric agricultural machinery. It is the product of the transmission ratios of the central drive and the final drive of the electric agricultural machinery. The transmission system of the electric agricultural machinery is equivalent to the rotational inertia at the output end of the AMT gearbox. This is the equivalent torque inertia at the input end of the AMT transmission. The output torque of the drive motor is... The equivalent resistance torque of the electric agricultural machinery is... Let be the pitch circle radius of the AMT transmission coupling sleeve.

3. The AMT shifting control method for electric agricultural machinery according to claim 1, characterized in that, S2 also includes: By adjusting the output torque of the drive motor of the electric agricultural machinery in real time, the frictional resistance torque on the meshing teeth of the AMT gearbox reaches the preset value.

4. The AMT shifting control method for electric agricultural machinery according to claim 1, characterized in that, The AMT shift control method for electric agricultural machinery also includes: After the electric agricultural machine completes the disengagement action, it determines whether the disengagement action was successful. If successful, it performs the engagement action; if unsuccessful, it returns to S1.

5. The AMT shifting control method for electric agricultural machinery according to claim 1, characterized in that, Calculating the target speed of the drive motor of the electric agricultural machinery includes: The target rotational speed is calculated by the predictive controller using the MPC model.

6. The AMT shifting control method for electric agricultural machinery according to claim 5, characterized in that, Controlling the difference between the current speed of the drive motor of the electric agricultural machinery and the target speed to be less than 50 rpm includes: After calculating the target rotational speed using the MPC model predictive controller, it is determined whether the electric agricultural machinery needs to increase its speed. If the electric agricultural machinery needs to increase its speed, the current speed of the drive motor of the electric agricultural machinery is controlled by fuzzy PID so that the difference between the current speed and the target speed is less than 50 rpm. If the electric agricultural machinery does not need to increase its speed, the energy recovery system of the electric agricultural machinery is activated, and the current speed of the drive motor of the electric agricultural machinery is controlled by the fuzzy PID control so that the difference between the current speed and the target speed is less than 50 rpm.

7. The AMT shifting control method for electric agricultural machinery according to claim 6, characterized in that, S5 also includes: Determine whether the difference between the current speed and the target speed is less than 50 rpm. If it is less than 50 rpm, then perform the gear shifting action; if it is greater than 50 rpm, then the target speed needs to be recalculated.

8. The AMT shifting control method for electric agricultural machinery according to claim 1, characterized in that, The AMT shift control method for electric agricultural machinery also includes: After the electric agricultural machine completes the gear shifting action, it is determined whether the gear shifting action was successful. If successful, the gear shifting action of the electric agricultural machine is completed; if unsuccessful, it returns to S4.

9. The AMT shifting control method for electric agricultural machinery according to claim 1, characterized in that, S3 includes: The disengagement action is performed by the shift motor of the electric agricultural machinery.

10. The AMT shift control method for electric agricultural machinery according to claim 1, characterized in that, S6 includes: The gear shifting action is performed by the gear shifting motor of the electric agricultural machinery.

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