A method for distributing power in a four-wheel drive tractor

Abstract

This invention relates to the field of tractor technology, specifically to a power distribution method for a four-wheel drive tractor. The method includes the following steps: Step S1, the control unit receives signals sent by an information acquisition unit, the received signals including power system output information, vehicle speed information, four-wheel speed information, and four-wheel vertical load information; Step S2, the control unit calculates the four-wheel slip ratio and the four-wheel vertical load ratio; Step S3, the control unit sends signals to the execution unit, the signals sent by the control unit are used to control the four-wheel torque distribution and four-wheel speed, wherein the four-wheel slip ratio is 10%-15%. Due to the technical solution of this application, the four-wheel torque distribution and four-wheel speed are dynamically adjusted according to real-time data changes, keeping the vehicle in optimal operating condition. Compared with the fixed four-wheel torque distribution and four-wheel speed in the prior art, the traction efficiency is increased by 8.7%, and energy consumption is reduced by 5.5%.

Description

Technical Field

[0001] This invention relates to the field of tractor technology, specifically to a power distribution method for a four-wheel drive tractor. Background Technology

[0002] Existing tractor four-wheel drive control systems, such as Chinese Patent 2022114831715, disclose a wheeled tractor four-wheel drive control system and its control method. The system includes a service brake signal acquisition device, a vehicle speed signal acquisition device, a four-wheel drive switch, a signal processing device, a pressure control device, and a four-wheel drive actuator. The service brake signal acquisition device is used to acquire service brake signals; the vehicle speed signal acquisition device is used to obtain the driving speed of the wheeled tractor; the four-wheel drive switch is used to send an electrical signal when manually opened; the four-wheel drive actuator includes a wet transfer case for four-wheel drive switching; the pressure control device is used to control the on / off of hydraulic oil entering the four-wheel drive actuator; and the signal processing device is used to collect various signals and issue control commands.

[0003] The above technical solution has the following disadvantages: it can switch between two-wheel drive and four-wheel drive, the power distribution of the four wheels adopts a fixed ratio, it cannot dynamically adjust the power distribution of the four wheels, it cannot make the vehicle work at its best, the traction efficiency is low, and the energy consumption is high. Summary of the Invention

[0004] The purpose of this invention is to provide a power distribution method for a four-wheel drive tractor that addresses the above problems by dynamically adjusting the torque distribution and speed of the four wheels based on real-time data changes.

[0005] To achieve the above objectives, this invention discloses a power distribution method for a four-wheel drive tractor, which includes the following steps: Step S1: The control unit receives signals sent by the information acquisition unit. The signals received by the control unit include power output information of the power system, vehicle speed information, four-wheel speed information, and four-wheel vertical load information.

[0006] This step is used to receive various vehicle data for subsequent use by the control unit.

[0007] Step S2: The control unit calculates the slip ratio of the four wheels and the vertical load ratio of the four wheels.

[0008] This step is used to calculate the slip ratio of the four wheels and the vertical load ratio of the four wheels, which is convenient for subsequent use by the control unit.

[0009] Step S3: The control unit sends a signal to the execution unit. The signal sent by the control unit is used to control the torque distribution and speed of the four wheels, wherein the slip ratio of the four wheels is 10%-15%.

[0010] This step is used to control the torque distribution and speed of the four wheels, so that the vehicle is in the best working condition.

[0011] Preferably, in step S1, the signal received by the control unit also includes wheel angle information.

[0012] This step is used to receive the vehicle's wheel angle information, which is then used by the subsequent control unit.

[0013] In step S2, the control unit determines whether the wheel angle in the current signal is greater than 2 degrees. If the wheel angle is greater than 2 degrees, the control unit calculates the ratio of the distance from the inner and outer wheels to the center of the turning circle.

[0014] This step is used to determine whether the wheel turning angle is greater than 2 degrees, which is convenient for subsequent use by the control unit.

[0015] In step S3, if the wheel angle is no more than 2 degrees, the torque distribution ratio of the four wheels is equal to the vertical load ratio of the four wheels; if the wheel angle is greater than 2 degrees, the torque distribution ratio of the front and rear wheels is equal to the vertical load ratio of the front and rear wheels, and the torque distribution ratio of the inner and outer wheels is equal to the ratio of the distances from the inner and outer wheels to the center of the turning circle.

[0016] When a vehicle turns, reducing the torque on the inner wheels and increasing the torque on the outer wheels helps the vehicle turn smoothly and maintains a reasonable four-wheel slip ratio.

[0017] Preferably, the wheel rotation angle is the rotation angle of the inner wheel.

[0018] Using the rotation angle of the inner wheel as the wheel rotation angle facilitates subsequent calculations by the control unit.

[0019] Preferably, in step S1, the frequency of the signal received by the control unit is 100Hz or higher.

[0020] Using this frequency balances the power distribution calculation requirements with the hardware performance of the control unit, resulting in low operating costs.

[0021] Preferably, in step S1, the control unit determines whether the difference between the vertical load of the wheel in the current signal and the vertical load of the wheel in the previous signal is greater than a preset value. If it is greater than the preset value, it is considered an invalid signal.

[0022] When the vehicle is operating, if it encounters obstacles such as clods of earth, the vertical load on the wheels will change suddenly. This instantaneous change does not affect the vehicle's operation, so the signal is considered invalid and does not affect the control unit's decision. However, if the soil quality or moisture content of the working area changes, the vertical load on the wheels will change over a long period of time. This change affects the vehicle's operation, so the signal is considered valid. The control unit incorporates this information into its decision to keep the vehicle in the optimal operating condition.

[0023] Preferably, in step S1, the control unit determines whether the difference between the vehicle speed in the current signal and the vehicle speed in the previous signal is greater than a preset value. If it is greater than the preset value, it is considered an invalid signal.

[0024] When a vehicle encounters obstacles such as clods of earth during operation, its speed will suddenly change. This instantaneous change does not affect the vehicle's operation, so the signal is considered invalid and does not affect the control unit's decision. However, if the soil quality or moisture content of the work site changes, the vehicle's speed will change over a long period of time. This change affects the vehicle's operation, so the signal is considered valid. The control unit incorporates this information into its decision to keep the vehicle in the optimal operating state.

[0025] Preferably, in the initial state, the vehicle is located on the work plot, the towed implement is at a preset depth, the torque distribution between the front and rear wheels is 40-50:60-50, the torque distribution between the left and right wheels is 1:1, the slip rate of the four wheels is 10%-20%, and step S1 begins after the vehicle speed reaches the preset value.

[0026] Before commencing operations, the driver drives the vehicle into the work area and then lowers the towed implement to a preset depth. The specific preset depth is based on existing technology and will not be elaborated upon here. The torque distribution ratio and four-wheel slip ratio used in this step facilitate vehicle start-up.

[0027] Preferably, the vehicle speed is preset to 0.5-10 km / h, and the vehicle acceleration is 0.1-1 m / s². 2 .

[0028] Specifically, when tilling the land, the preset vehicle speed is 2.5-10 km / h, and the vehicle acceleration is 0.3-1 m / s². 2 When sowing operations are required, the vehicle speed is preset to 4.5-7.5 km / h, and the vehicle acceleration is 0.5-0.8 m / s². 2 When trenching is required, the vehicle speed is preset to 0.5-1 km / h, and the vehicle acceleration is 0.1-0.2 m / s². 2 By using the vehicle speed and acceleration parameters in this step, the vehicle runs smoothly and the work efficiency is high.

[0029] In summary, the beneficial effects of the present invention are as follows: due to the technical solution of this application, the torque distribution and speed of the four wheels are dynamically adjusted according to real-time data changes, so that the vehicle is in the best working state. Compared with the fixed torque distribution and speed of the four wheels in the prior art, the traction efficiency is increased by 8.7% and the energy consumption is reduced by 5.5%. Attached Figure Description

[0030] Figure 1 This is a flowchart illustrating a power distribution method for a four-wheel drive tractor according to the present invention. Detailed Implementation

[0031] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0032] like Figure 1 As shown, a power distribution method for a four-wheel drive tractor includes the following steps: Initially, the vehicle is located on the work area, and the towed implement is at a preset depth. The torque distribution between the front and rear wheels is 40-50:60-50, preferably 40:60, 45:55, or 50:50. The torque distribution between the left and right wheels is 1:1, and the four-wheel slip ratio is 10%-20%. Step S1 begins after the vehicle speed reaches the preset value. Before operation, the driver drives the vehicle into the work area and then lowers the towed implement to the preset depth. The specific preset depth is based on existing technology and will not be elaborated here. The torque distribution ratio and four-wheel slip ratio used in this step facilitate vehicle start-up. The preset vehicle speed is 0.5-10 km / h, and the vehicle acceleration is 0.1-1 m / s². 2 Specifically, when tilling the land, the preset vehicle speed is 2.5-10 km / h, and the vehicle acceleration is 0.3-1 m / s². 2 When sowing operations are required, the vehicle speed is preset to 4.5-7.5 km / h, and the vehicle acceleration is 0.5-0.8 m / s². 2 When trenching is required, the vehicle speed is preset to 0.5-1 km / h, and the vehicle acceleration is 0.1-0.2 m / s². 2 By using the vehicle speed and acceleration parameters in this step, the vehicle runs smoothly and the work efficiency is high.

[0033] In step S1, the control unit receives signals from the information acquisition unit. These signals include power system output information, vehicle speed information, four-wheel speed information, and four-wheel vertical load information. How the information acquisition unit collects these information is based on existing technology and will not be elaborated here. Similarly, how the control unit receives the signals from the information acquisition unit is also based on existing technology and will not be elaborated here. This step is used to receive various vehicle data for subsequent use by the control unit. In step S1, the control unit also receives wheel angle information; this step is used to receive the vehicle's wheel angle information for subsequent use by the control unit. In step S1, the wheel angle is the angle of the inner wheel. Using the inner wheel angle as the wheel angle facilitates calculation by the control unit. In step S1, the frequency of the signals received by the control unit is above 100Hz. Using this frequency balances the power distribution calculation requirements with the control unit's hardware performance, resulting in low operating costs. In step S1, the control unit determines whether the difference between the vertical load of the wheel in the current signal and the vertical load of the same wheel in the previous signal is greater than a preset value. If it is greater than the preset value, the signal is considered invalid. During vehicle operation, if obstacles such as clods of earth are encountered, the vertical load of the wheel may change suddenly. This instantaneous change does not affect vehicle operation, so the signal is considered invalid and does not affect the control unit's decision. However, if the soil quality or moisture content of the work area changes, the vertical load of the wheel will change over a long period. This change affects vehicle operation, so the signal is considered valid, and the control unit incorporates this information into its decision to ensure the vehicle is in optimal operating condition. In step S1, the control unit determines whether the difference between the vehicle speed in the current signal and the vehicle speed in the previous signal is greater than a preset value. If it is greater than the preset value, the signal is considered invalid. When a vehicle encounters obstacles such as clods of earth during operation, its speed will suddenly change. This instantaneous change does not affect the vehicle's operation, so the signal is considered invalid and does not affect the control unit's decision. However, if the soil quality or moisture content of the work site changes, the vehicle's speed will change over a long period of time. This change affects the vehicle's operation, so the signal is considered valid. The control unit incorporates this information into its decision to keep the vehicle in the optimal operating state.

[0034] Step S2: The control unit calculates the four-wheel slip ratio and the four-wheel vertical load ratio. This step is used to calculate the four-wheel slip ratio and the four-wheel vertical load ratio for subsequent use by the control unit. In step S2, the control unit determines whether the wheel angle in the current signal is greater than 2 degrees. If the wheel angle is greater than 2 degrees, the control unit calculates the ratio of the distance from the inner and outer wheels to the turning center. This step is used to determine whether the wheel angle is greater than 2 degrees for subsequent use by the control unit.

[0035] In step S3, the control unit sends a signal to the execution unit. This signal controls the torque distribution and speed of the four wheels, with a wheel slip ratio of 10%-15%. The execution unit controls the torque distribution and speed using existing technology, such as independent hub motors for each wheel, which will not be elaborated here. This step controls the torque distribution and speed of the four wheels to ensure the vehicle is in optimal operating condition. In step S3, if the wheel angle is no greater than 2 degrees, the torque distribution ratio is equal to the vertical load ratio of the four wheels; if the wheel angle is greater than 2 degrees, the torque distribution ratio between the front and rear wheels is equal to the vertical load ratio of the front and rear wheels, and the torque distribution ratio between the inner and outer wheels is equal to the ratio of the distances from the inner and outer wheels to the turning center. When the vehicle turns, reducing the torque of the inner wheels and increasing the torque of the outer wheels helps the vehicle turn smoothly and maintains a reasonable wheel slip ratio.

[0036] Because of the technical solution of this application, the torque distribution and speed of the four wheels are dynamically adjusted according to real-time data changes, so that the vehicle is in the best working state. Compared with the fixed torque distribution and speed of the four wheels in the prior art, the traction efficiency is increased by 8.7% and the energy consumption is reduced by 5.5%.

[0037] In this invention, the circuits for acquiring the various sensor signals and controlling the servo driver and servo motor are all existing technology circuits. The connections between the various electrical components are also conventional circuit connection structures, which are not the focus of this invention and will not be elaborated upon here. Furthermore, the signals acquired and transmitted by the control circuit only involve two types: high-level signals and low-level signals. These two levels of signals correspond to the on / off states of the relevant electrical components, which can be achieved using existing conventional circuit connection structures without involving computer programming.

[0038] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and substitutions can be made without departing from the technical principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention.

Claims

1. A power distribution method for a four-wheel drive tractor, characterized in that, Includes the following steps: Step S1: The control unit receives signals sent by the information acquisition unit. The signals received by the control unit include power output information of the power system, vehicle speed information, four-wheel speed information, and four-wheel vertical load information. Step S2: The control unit calculates the slip ratio of the four wheels and the vertical load ratio of the four wheels; Step S3: The control unit sends a signal to the execution unit. The signal sent by the control unit is used to control the torque distribution and speed of the four wheels, wherein the slip ratio of the four wheels is 10%-15%.

2. The power distribution method for a four-wheel drive tractor as described in claim 1, characterized in that, In step S1, the signals received by the control unit also include wheel angle information; In step S2, the control unit determines whether the wheel angle in the current signal is greater than 2 degrees. If the wheel angle is greater than 2 degrees, the control unit calculates the ratio of the distance from the inner and outer wheels to the turning center. In step S3, if the wheel angle is no more than 2 degrees, the torque distribution ratio of the four wheels is equal to the vertical load ratio of the four wheels; if the wheel angle is greater than 2 degrees, the torque distribution ratio of the front and rear wheels is equal to the vertical load ratio of the front and rear wheels, and the torque distribution ratio of the inner and outer wheels is equal to the ratio of the distances from the inner and outer wheels to the center of the turning circle.

3. The power distribution method for a four-wheel drive tractor as described in claim 2, characterized in that, In step S1, the wheel rotation angle is the rotation angle of the inner wheel.

4. The power distribution method for a four-wheel drive tractor as described in claims 1 to 3, characterized in that, In step S1, the frequency of the signal received by the control unit is above 100Hz.

5. The power distribution method for a four-wheel drive tractor as described in any one of claims 1 to 3, characterized in that, In step S1, the control unit determines whether the difference between the vertical load of the wheel in the current signal and the vertical load of the wheel in the previous signal is greater than a preset value. If it is greater than the preset value, it is considered an invalid signal.

6. The power distribution method for a four-wheel drive tractor as described in any one of claims 1 to 3, characterized in that, In step S1, the control unit determines whether the difference between the vehicle speed in the current signal and the vehicle speed in the previous signal is greater than a preset value. If it is greater than the preset value, it is considered an invalid signal.

7. The power distribution method for a four-wheel drive tractor as described in any one of claims 1 to 3, characterized in that, In the initial state, the vehicle is located on the work plot, the towed implement is at a preset depth, the torque distribution of the front and rear wheels is 40-50:60-50, the torque distribution of the left and right wheels is 1:1, the slip rate of the four wheels is 10%-20%, and step S1 begins after the vehicle speed reaches the preset value.

8. The power distribution method for a four-wheel drive tractor as described in claim 7, characterized in that, The vehicle speed is preset to 0.5-10 km / h, and the vehicle acceleration is preset to 0.1-1 m / s². 2 .

Images