Dual-motor coupling driving electric tractor power system and electric tractor

Abstract

The utility model provides a dual-motor coupling drive electric tractor power system and an electric tractor. The dual-motor coupling drive electric tractor power system comprises a driving intention recognition module, a mode recognition module and a power distribution module. The driving intention recognition module comprises an accelerator pedal and an accelerator pedal angle sensor; the mode identification module comprises a main motor current and voltage sensor and a speed regulation motor current and voltage sensor; the power distribution module comprises a main motor rotating speed torque sensor, a speed regulation motor rotating speed torque sensor, a main motor, a speed regulation motor, a main motor driver, a speed regulation motor driver, a coupling box, a gearbox, a PTO rotating speed torque sensor, a high-voltage battery, a high-voltage battery controller and a fuzzy controller. Torque is reasonably distributed to the main motor and the adjustable-speed motor, and the cruising ability and the working efficiency of the tractor are improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of agricultural machinery, and in particular relates to a dual-motor coupling driven electric tractor power system and an electric tractor. Background Art

[0002] my country's annual consumption of non-renewable energy such as oil and coal is increasing, leading to the aggravation of energy crisis and environmental pollution problems such as greenhouse effect and haze. Among them, agricultural machinery operations generally have problems such as high fuel consumption, low efficiency and high carbon emissions.

[0003] At present, the most effective way to change tractor emissions is to use electric motors, which can reduce emissions by 80%, reduce noise by 50%, and reach 78% of rated power when working. It can replace diesel internal combustion engines and be used in agricultural work. On the one hand, agricultural diesel consumption is large, and the dual-motor system can replace diesel and reduce CO2 and SO2 emissions; on the other hand, the control strategy of dual-motor driven agricultural electric tractors can be applied and promoted on similar models, and has strong universality. However, most of my country's pure electric tractors are currently driven by a single motor. When faced with complex working conditions, they cannot meet the power required by the machinery, and the single-motor tractor has poor endurance and low working efficiency. Therefore, the research on dual-motor coupled electric tractors is of great strategic significance to improve the efficient operation of machinery and strengthen the reasonable distribution of mechanical energy. Summary of the invention

[0004] In view of the above technical problems, the utility model provides a dual-motor coupling-driven electric tractor power system and an electric tractor, which reasonably distribute the torque to the main motor and the speed regulating motor, thereby improving the endurance and working efficiency of the tractor.

[0005] The technical solution adopted by the utility model to solve its technical problems is:

[0006] A dual-motor coupling-driven electric tractor power system, comprising a driving intention recognition module, a pattern recognition module and a power distribution module;

[0007] The driving intention recognition module includes an accelerator pedal and an accelerator pedal angle sensor; the accelerator pedal angle sensor is installed on the accelerator pedal;

[0008] The pattern recognition module includes a main motor current and voltage sensor and a speed regulating motor current and voltage sensor;

[0009] The power distribution module includes a main motor speed torque sensor, a speed regulating motor speed torque sensor, a main motor, a speed regulating motor, a main motor driver, a speed regulating motor driver, a coupling box, a gearbox, a PTO speed torque sensor, a high-voltage battery, a high-voltage battery controller and a fuzzy controller; the high-voltage battery is connected to the main motor and the speed regulating motor respectively, the main motor and the speed regulating motor are connected through a coupling box, the main motor driver is connected to the main motor, and the speed regulating motor driver is connected to the speed regulating motor; the gearbox is connected to the main motor driver and the speed regulating motor driver respectively;

[0010] The main motor speed and torque sensor is installed on the output shaft of the main motor, the speed regulating motor speed and torque sensor is installed on the output shaft of the speed regulating motor, the main motor current and voltage sensor is connected to the output line of the main motor driver; the speed regulating motor current and voltage sensor is connected to the output line of the speed regulating motor driver, and the PTO speed and torque sensor is installed on the PTO output shaft of the gearbox;

[0011] The accelerator pedal angle sensor, display terminal, main motor speed torque sensor, speed regulating motor speed torque sensor, speed regulating motor current voltage sensor, main motor current voltage sensor, PTO speed torque sensor, high voltage battery controller and fuzzy controller are respectively connected to the tractor master controller.

[0012] In the above solution, a planetary gear is provided in the coupling box; the main motor and the speed regulating motor are coupled and connected via the planetary gear.

[0013] In the above scheme, the accelerator pedal angle sensor is used to detect the opening of the accelerator pedal and transmit it to the tractor master controller, and the tractor master controller calculates the basic torque of the tractor according to the opening of the accelerator pedal.

[0014] In the above scheme, the main motor current and voltage sensor is used to detect the main motor current and voltage and transmit it to the tractor master controller; the speed regulating motor current and voltage sensor is used to detect the speed regulating motor current and voltage and transmit it to the tractor master controller;

[0015] The tractor master controller calculates the power of the main motor and the speed regulating motor in separate working modes, and the power of the main motor and the speed regulating motor in coupled working mode according to the current and voltage detected by the main motor current and voltage sensor and the speed regulating motor current and voltage sensor, and obtains the minimum power by comparison.

[0016] In the above scheme, the main motor speed and torque sensor is used to detect the main motor speed and torque and transmit it to the tractor master controller; the speed regulating motor speed and torque sensor is used to detect the speed regulating motor speed and torque and transmit it to the tractor master controller; the PTO speed and torque sensor is used to detect the PTO speed and torque and transmit it to the tractor master controller.

[0017] In the above scheme, the high-voltage battery controller transmits the SOC value of the high-voltage battery to the tractor main controller.

[0018] In the above solution, the pattern recognition module also includes a display terminal; the display terminal is connected to the tractor master controller and is used to display data.

[0019] An electric tractor comprises the dual-motor coupling-driven electric tractor power system.

[0020] Compared with the prior art, the beneficial effects of the utility model are:

[0021] The dual-motor coupling-driven electric tractor power system of the utility model distributes torque reasonably to the main motor and the speed regulating motor through a driving intention recognition module, a pattern recognition module and a power distribution module, thereby improving the endurance and working efficiency of the tractor. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0023] Figure 1 It is a schematic diagram of the structure of a power system of an electric tractor driven by dual motor coupling according to an embodiment of the utility model;

[0024] Figure 2 It is a schematic diagram of the structure of a driving intention and pattern recognition module of an embodiment of the utility model;

[0025] Figure 3 It is a structural schematic diagram of a power distribution module according to one embodiment of the utility model.

[0026] Figure 4 This is a tractor transition working condition diagram of one embodiment of the utility model.

[0027] Figure 5 It is a vehicle speed tracking diagram under transition conditions of one implementation mode of the utility model.

[0028] Figure 6 It is the offline simulation change curve of battery SOC of electric tractor under plowing and rotary tillage conditions.

[0029] Figure 7 This is a battery SOC change curve of an electric tractor tested under plowing conditions.

[0030] Figure 8 It is a battery SOC change curve of the electric tractor test under rotary tillage conditions.

[0031] Figure markings: 1. Driving intention recognition module, 2. Pattern recognition module, 3. Power distribution module, 4. Clutch pedal, 5. Accelerator pedal 6. Brake pedal, 7. Shift handle, 8. Key switch, 9. Main motor speed and torque sensor, 10. Speed ​​control motor speed and torque sensor, 11. Speed ​​control motor current and voltage sensor, 12. Main motor current and voltage sensor, 13. Speed ​​control motor, 14. Main motor, 15. Speed ​​control motor driver, 16. Main motor driver, 17. Display terminal, 18. Coupling box, 19. Gearbox, 20. PTO speed and torque sensor. DETAILED DESCRIPTION

[0032] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0033] In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "front", "back", "left", "right", "up", "down", "axial", "radial", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present utility model, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0034] In the present invention, unless otherwise clearly specified and limited, the terms "install", "connect", "connect", "fix" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined purpose of the utility model, the specific implementation method, structure, characteristics and effects of the dual-motor coupled drive electric tractor proposed by the utility model are described in detail below in combination with the accompanying drawings and preferred embodiments. Example

[0036] like Figure 1 As shown, a preferred embodiment of the dual-motor coupled electric tractor power system of the utility model is shown. The dual-motor coupled electric tractor power system includes a driving intention recognition module 1, a pattern recognition module 2 and a power distribution module 3.

[0037] The driving intention recognition module 1 includes an accelerator pedal 5 and an accelerator pedal angle sensor; the accelerator pedal angle sensor is installed on the accelerator pedal 5, and the accelerator pedal angle sensor is used to detect the opening of the accelerator pedal 5 and transmit it to the tractor master controller, and the tractor master controller calculates the basic torque of the tractor according to the opening of the accelerator pedal 5.

[0038] The pattern recognition module 2 includes a main motor current and voltage sensor 12 and a speed regulating motor current and voltage sensor 11;

[0039] The main motor current and voltage sensor 12 is used to detect the current and voltage of the main motor and transmit it to the tractor main controller; the speed regulating motor current and voltage sensor 11 is used to detect the current and voltage of the speed regulating motor 13 and transmit it to the tractor main controller; the tractor main controller calculates the power of the main motor 14 and the speed regulating motor 13 in the separate working mode and the power of the main motor 14 and the speed regulating motor 13 in the coupled working mode according to the current and voltage detected by the main motor current and voltage sensor 12 and the speed regulating motor current and voltage sensor 11, and obtains the minimum power by comparison.

[0040] The power distribution module 3 includes a main motor speed torque sensor 9, a speed regulating motor speed torque sensor 10, a main motor 14, a speed regulating motor 13, a main motor driver 16, a speed regulating motor driver 15, a coupling box 18, a gearbox 19, a PTO speed torque sensor 20, a high-voltage battery, a high-voltage battery controller and a fuzzy controller; the high-voltage battery is connected to the main motor 14 and the speed regulating motor 13 respectively, the main motor 14 and the speed regulating motor 13 are connected through the coupling box 18, the main motor driver 16 is connected to the main motor 14, and the speed regulating motor driver 15 is connected to the speed regulating motor 13; the gearbox 19 is connected to the main motor driver 16 and the speed regulating motor driver 15 respectively;

[0041] The main motor speed and torque sensor 9 is installed on the output shaft of the main motor 14, the speed regulating motor speed and torque sensor 10 is installed on the output shaft of the speed regulating motor 13, the main motor current and voltage sensor 12 is connected to the output line of the main motor driver 16; the speed regulating motor current and voltage sensor 11 is connected to the output line of the speed regulating motor driver 15, and the PTO speed and torque sensor 20 is installed on the PTO output shaft of the gearbox 19; the main motor speed and torque sensor 9 is used to detect the main motor speed and torque and transmit it to the tractor master controller; the speed regulating motor speed and torque sensor 10 is used to detect the speed regulating motor speed and torque and transmit it to the tractor master controller; the PTO speed and torque sensor 20 is used to detect the PTO speed and torque and transmit it to the tractor master controller.

[0042] The accelerator pedal angle sensor, display terminal 17, main motor speed torque sensor 9, speed regulating motor speed torque sensor 10, speed regulating motor current voltage sensor 11, main motor current voltage sensor 12, PTO speed torque sensor 20, high-voltage battery controller and fuzzy controller are respectively connected to the tractor master controller. The high-voltage battery controller transmits the SOC value of the high-voltage battery to the tractor master controller.

[0043] The pattern recognition module 2 and the power distribution module 3 form an energy management strategy module.

[0044] In a specific embodiment of the present invention, the target vehicle speed or PTO speed is used as input, the driver module steps on the pedal, and the pedal information is output and transmitted to the driving intention recognition module 1. After the driving intention recognition module 1 obtains the total required torque, it enters the mode recognition module 2 and the power distribution module 3. The mode recognition module 2 switches to the minimum power mode. After the fuzzy controller of the power distribution module 3 calculates the speed torque of the main motor 14 and the speed regulating motor 13, the speed torque of the main motor 14 and the speed regulating motor 13 is controlled to change, thereby changing the coupling box and the gearbox in the power coupling device, as well as the traction and PTO module. The traction and PTO module includes two rear-wheel drive wheels and a PTO speed torque sensor 20. The battery supplies power to the main motor 14, the speed regulating motor 13 and the lifter module. The feedback part includes: the traction and PTO module feeds back the actual PTO output shaft speed torque of the gearbox 19 to the driver module, the driving intention recognition module 1 and the pattern recognition module 2. The BMS battery management system feeds back the power component information in the battery controller to the pattern recognition module 2. At the same time, the BMS battery management system of the electric tractor, the main motor 14 and the speed regulating motor 13 together feed back the power component information to the driving intention recognition module 1.

[0045] According to this embodiment, preferably, a planetary gear is provided in the coupling box 18; and the main motor 14 and the speed regulating motor 13 are coupled and connected via the planetary gear.

[0046] According to this embodiment, preferably, the tractor master controller also includes an ANFIS model of the prior art; the ANFIS model is a neural network based on fuzzy reasoning, including a 5-layer network structure; the opening of the accelerator pedal 5 and the pedal opening change rate, i.e., acceleration, are used as fuzzy inputs of the ANFIS model, and the compensation torque is used as the fuzzy output, and the basic torque of the tractor is added to the compensation torque to calculate the total required torque of the tractor.

[0047] The fuzzy controller uses the SOC value of the high-voltage battery and the total required torque of the tractor as input values, outputs the motor torque distribution coefficient, and calculates the torque of the main motor 14 and the speed regulating motor 13. If the actual electric power of the main motor 14 and the speed regulating motor 13 is less than the minimum electric power, the tractor master controller controls the main motor driver 16 and the speed regulating motor driver 15 according to the torque of the main motor 14 and the speed regulating motor 13 calculated by the fuzzy controller, so that the main motor 14 and the speed regulating motor 13 drive the tractor to work.

[0048] According to this embodiment, preferably, the pattern recognition module 2 further includes a display terminal 17; the display terminal 17 is connected to the tractor master controller for displaying data.

[0049] The tractor further comprises a clutch pedal 4 , a brake pedal 6 , a shift handle 7 and a key switch 8 .

[0050] The utility model analyzes the driving intention recognition module 1 to obtain the basic torque for driving the electric tractor, and then distributes the motor speed torque in real time according to the principle of minimum power and maximum energy utilization.

[0051] In order to select the most economical working mode, the utility model calculates the power of the three driving modes, namely, the independent working mode of the main motor 14 and the speed regulating motor 13, and the coupled working mode of the main motor 14 and the speed regulating motor 13, and compares them to obtain the minimum power, and then selects the most suitable driving mode.

[0052] The utility model realizes power transmission by coupling the main motor 14 and the speed regulating motor 13 with the help of planetary gears. A fuzzy controller with better robustness is selected and embedded in the tractor master controller. The fuzzy controller calculates the torque of the main motor 14 and the speed regulating motor 13 through formula 1 and formula 2.

[0053] Formula (1)

[0054] Formula (2)

[0055] In the formula, is the main motor working torque, is the working torque of the speed regulating motor, k is the transmission ratio of the planetary gear, is the reduction ratio of the main motor, is the motor torque distribution coefficient.

[0056] The tractor master controller controls the main motor driver 16 and the speed regulating motor driver 15 to adjust the speed torque of the main motor 14 and the speed regulating motor 13 according to the speed torque of the main motor 14 and the speed regulating motor 13 calculated by the fuzzy controller, and reasonably distributes the torque to the main motor 14 and the speed regulating motor 13 to ensure that sufficient power is provided without excessive loss of battery energy, thereby improving the tractor's endurance and work efficiency, and improving the economy and power performance of the entire vehicle.

[0057] The utility model uses a driving intention recognition module 1 to determine the basic torque and compensates the torque through an ANFIS model; uses a pattern recognition module 2 to select the minimum power under the working condition of the machine; and uses a power distribution module 3 to reasonably distribute the torque to a main motor 14 and a speed regulating motor 13.

[0058] Example 2

[0059] An electric tractor includes the dual-motor coupled electric tractor power system described in Example 1, and thus has the beneficial effects of Example 1, which will not be described in detail here.

[0060] The scientific rationality of the electric tractor under the condition of field transfer is verified through simulation and experiment:

[0061] Figure 4 The electric tractor transfer condition shown in the figure is used as the input condition of the dual-motor coupling drive electric tractor simulation system, and a comparison diagram of the target and actual two speeds is obtained, as shown in Figure 5 As shown, it can be found that under the conditions of transition, the vehicle speeds under the simulation and demand conditions are very consistent, and the vehicle speed presented by the simulation model also has good followability, which verifies that the electric tractor including the dual-motor coupled drive tractor power system is scientific and reasonable.

[0062] The electric tractor was operated at a constant speed of 2 km / h and 3 km / h for 1000 seconds under plowing and rotary tillage conditions, respectively, and the following Figure 6 The battery SOC change curve shown in Figure 2. Figure 6 It can be seen that the fuzzy control strategy can better control the torque distribution of the motor according to the battery state of charge SOC and the required torque of the whole machine, so that the battery SOC is kept within a relatively stable range, which is beneficial to prolonging the battery life.

[0063] In the simulation of the plowing operation of the electric tractor, the main motor 14 and the speed regulating motor 13 only need to pull the plow and other agricultural implements for walking operation, and the PTO is not loaded. When plowing, ∆SOC=0.12, such as Figure 7 As shown, combined Figure 6 and 7 It can be seen that the SOC change trends of the test and simulation are basically consistent, the curves are relatively flat, and the SOC change value obtained by the test is smaller than that of the simulation, and the battery consumes less energy.

[0064] Figure 8 The rotary tillage operation simulates the main motor driving the wheels while driving the PTO operation. The tractor runs the main motor and the speed regulating motor at the same time. When the tractor is in rotary tillage operation, the battery state of charge SOC decreases steadily, ∆SOC=0.08, combined with Figure 6 and 8 It can be seen that the SOC change trends of the test and simulation are basically consistent, the curves are relatively gentle, and the SOC change value obtained by the test is smaller than that of the simulation, and the battery consumes less energy. It can be seen that the power system can reasonably distribute the output torque of the dual motors, and the battery SOC changes smoothly, which verifies that the real-time and functionality of the power system are good.

[0065] The series of detailed descriptions listed above are only specific descriptions of feasible embodiments of the present invention. They are not intended to limit the protection scope of the present invention. All equivalent embodiments or changes that do not deviate from the technical spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A dual-motor coupled electric tractor power system, characterized in that: It includes a driving intention recognition module (1), a pattern recognition module (2) and a power distribution module (3); The driving intention recognition module (1) comprises an accelerator pedal (5) and an accelerator pedal angle sensor; the accelerator pedal angle sensor is mounted on the accelerator pedal (5); The pattern recognition module (2) comprises a main motor current and voltage sensor (12) and a speed regulating motor current and voltage sensor (11); The power distribution module (3) comprises a main motor speed torque sensor (9), a speed regulating motor speed torque sensor (10), a main motor (14), a speed regulating motor (13), a main motor driver (16), a speed regulating motor driver (15), a coupling box (18), a gearbox (19), a PTO speed torque sensor (20), a high-voltage battery, a high-voltage battery controller and a fuzzy controller; the high-voltage battery is connected to the main motor (14) and the speed regulating motor (13) respectively, the main motor (14) and the speed regulating motor (13) are connected via the coupling box (18), the main motor driver (16) is connected to the main motor (14), and the speed regulating motor driver (15) is connected to the main motor (14). (15) is connected to the speed regulating motor (13); the gearbox (19) is respectively connected to the main motor driver (16) and the speed regulating motor driver (15); the main motor speed torque sensor (9) is installed on the output shaft of the main motor (14), the speed regulating motor speed torque sensor (10) is installed on the output shaft of the speed regulating motor (13), the main motor current voltage sensor (12) is connected to the output line of the main motor driver (16); the speed regulating motor current voltage sensor (11) is connected to the output line of the speed regulating motor driver (15), and the PTO speed torque sensor (20) is installed on the PTO output shaft of the gearbox (19); The accelerator pedal angle sensor, the display terminal (17), the main motor speed torque sensor (9), the speed regulating motor speed torque sensor (10), the speed regulating motor current and voltage sensor (11), the main motor current and voltage sensor (12), the PTO speed torque sensor (20), the high-voltage battery controller and the fuzzy controller are respectively connected to the tractor master controller.

2. The dual-motor coupled electric tractor power system according to claim 1, characterized in that: A planetary gear is provided in the coupling box (18); the main motor (14) and the speed regulating motor (13) are coupled and connected via the planetary gear.

3. The dual-motor coupled drive electric tractor power system according to claim 1, characterized in that: The accelerator pedal angle sensor is used to detect the opening degree of the accelerator pedal (5) and transmit the information to the tractor master controller, which calculates the basic torque for tractor travel based on the opening degree of the accelerator pedal (5).

4. The dual-motor coupled drive electric tractor power system according to claim 1, characterized in that: The main motor current and voltage sensor (12) is used to detect the current and voltage of the main motor and transmit it to the tractor master controller; the speed regulating motor current and voltage sensor (11) is used to detect the current and voltage of the speed regulating motor (13) and transmit it to the tractor master controller; The tractor master controller calculates the power of the main motor (14) and the speed regulating motor (13) in a separate working mode, and the power of the main motor (14) and the speed regulating motor (13) in a coupled working mode, based on the current and voltage detected by the main motor current and voltage sensor (12) and the speed regulating motor current and voltage sensor (11), and compares them to obtain the minimum power.

5. The dual-motor coupled drive electric tractor power system according to claim 1, characterized in that: The main motor speed torque sensor (9) is used to detect the main motor speed torque and transmit it to the tractor master controller; the speed regulating motor speed torque sensor (10) is used to detect the speed regulating motor speed torque and transmit it to the tractor master controller; the PTO speed torque sensor (20) is used to detect the PTO speed torque and transmit it to the tractor master controller.

6. The dual-motor coupled drive electric tractor power system according to claim 1, characterized in that: The high-voltage battery controller transmits the SOC value of the high-voltage battery to the tractor main controller.

7. The dual-motor coupled electric tractor power system according to claim 1, characterized in that: The pattern recognition module (2) further comprises a display terminal (17); the display terminal (17) is connected to the tractor master controller and is used to display data.

8. An electric tractor, characterized in that: A dual-motor coupled electric tractor power system comprising any one of claims 1-7.

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