Parallel-parallel hybrid tractor power system and tractor

Abstract

The present invention relates to the technical field of tractors, and discloses a parallel-parallel hybrid power tractor power system and a tractor. The output shaft of the engine is connected to the generator through the main shaft of the transfer case, the generator is connected to the electric motor through an electronically controlled clutch, the generator and the electric motor are both electrically connected to an electric coupling device, and the electric coupling device is electrically connected to an electric energy storage device; the electric motor is connected to the AMT gearbox, and the AMT gearbox is connected to the wheels through the rear axle; the output shaft of the transfer case is connected to the power take-off device (PTO) through the rear axle; the main shaft and the output shaft of the transfer case are meshed and connected. The present invention can provide different power drive modes under different working conditions, improve the power economy of the tractor and reduce pollution emissions; the power transmission routes of the travel transmission mechanism and the power take-off device are independent of each other and do not interfere with each other; the power system has a simple structure, does not require a complex gearbox, occupies a small space, and is conducive to the layout of the entire vehicle.

Description

Technical Field

[0001] The present invention relates to the technical field of tractors, and in particular to a parallel-parallel hybrid power tractor power system and a tractor. Background Art

[0002] Tractors are the primary power machinery in agricultural production. Currently, most tractors in my country are powered by fuel engines. These traditional tractors suffer from low traction efficiency, high energy consumption, and high exhaust particulate matter emissions, which seriously pollute the environment. While pure electric tractors offer advantages such as low emissions and zero pollution, their technology is still immature and suffers from shortcomings such as limited endurance. Hybrid tractors can address these issues with both traditional and pure electric tractors.

[0003] Hybrid power systems are divided into series hybrid power systems, parallel hybrid power systems and parallel-parallel hybrid power systems. The parallel-parallel power system combines the advantages of series and parallel hybrid power systems and can better adapt to the complex operating conditions of tractors.

[0004] In the existing technology, although the hybrid tractor power system meets the torque and traction requirements of various tractor operating modes to a certain extent, the system structure is complex and has great requirements on the tractor layout space, making it difficult to apply in practice. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a parallel-parallel hybrid power tractor power system and a tractor in view of the problems existing in the prior art.

[0006] To solve the above technical problems, an embodiment of the present invention provides a parallel-parallel hybrid tractor power system, comprising: an engine, a transfer case, a generator, an electronically controlled clutch, an electric motor, an electric coupling device, an electric energy storage device, an automated manual transmission (AMT) gearbox, a rear axle, wheels, and a power take-off (PTO) device; the output shaft of the engine is transmission-connected to the generator via the main shaft of the transfer case, the generator is transmission-connected to the electric motor via the electronically controlled clutch, the electric motor is transmission-connected to the AMT gearbox, and the AMT gearbox is transmission-connected to the wheels via the rear axle; the generator and the electric motor are both electrically connected to the electric coupling device, which is electrically connected to the electric coupling device; and the main shaft and output shaft of the transfer case are meshed and transmission-connected via a constant mesh gear set.

[0007] The beneficial effects of the present invention are as follows: the travel transmission mechanism of the parallel-parallel hybrid power tractor power system transmits power to the rear axle through the engine, generator, electronically controlled clutch, electric motor, and two-speed automatic transmission manual manual gearbox, and outputs power to the wheels through the rear axle; the engine, generator, and electric motor in the travel transmission mechanism are coaxially arranged, and the generator and electric motor can achieve power coupling through the electronically controlled clutch; and the power transmission routes of the travel mechanism and the power output device are independent of each other and do not interfere with each other; the present invention can provide different power drive modes under different working conditions, improve the power economy of the tractor and reduce pollution emissions; and can simultaneously meet the requirements of vehicle speed, torque, and traction under various working conditions; and the power system has a simple structure, does not require a complex gearbox, occupies a small space, and is conducive to the layout of the entire vehicle.

[0008] On the basis of the above technical solution, the present invention can also be improved as follows.

[0009] Furthermore, the electronically controlled clutch adopts a dry clutch, a wet clutch, an electromagnetic clutch, an electronically controlled pneumatic clutch, an electronically controlled hydraulic clutch or an electronically controlled electric clutch.

[0010] The beneficial effects of adopting the above further solution are: adding a clutch between the generator and the electric motor can realize flexible switching between multiple modes such as independent engine drive, independent electric motor drive, engine direct drive and electric drive superposition drive.

[0011] Furthermore, the AMT gearbox adopts a two-speed AMT gearbox.

[0012] The beneficial effects of adopting the above-mentioned further scheme are as follows: the power transmission routes of the walking mechanism and the power output device are independent of each other and do not interfere with each other. The AMT only requires two gears (one working gear and one transport gear), and adopts an automatic shifting mechanism, which makes the gearbox structure simple and easy to arrange. At the same time, it is easy to automatically control and remotely control the unmanned driving system.

[0013] To solve the above technical problems, an embodiment of the present invention provides a tractor, including a vehicle controller, an engine controller, a generator controller and a motor controller, and also includes the parallel-parallel hybrid power tractor power system described in the above technical solution; the vehicle controller is electrically connected to the engine controller, generator controller, motor controller, electronically controlled clutch and AMT gearbox.

[0014] The beneficial effects of the present invention are as follows: the vehicle controller of the present invention controls the operation of the engine, generator and motor respectively through the engine controller, generator controller and motor controller, directly controls the operation of the electronically controlled clutch and the AMT gearbox, can provide different power drive modes under different working conditions, improve the power economy of the tractor and reduce pollution emissions; can simultaneously meet the requirements of vehicle speed, torque and traction under various working conditions; and the power system has a simple structure, does not require a complex gearbox, occupies a small space, and is conducive to the layout of the vehicle.

[0015] On the basis of the above technical solution, the present invention can also be improved as follows.

[0016] Furthermore, the vehicle controller is used to obtain the vehicle speed and load size, and control the working status of the engine, generator, electronically controlled clutch and motor according to the vehicle speed, load size and preset control strategy, so as to realize automatic switching of different power drive modes under different working conditions.

[0017] The beneficial effects of adopting the above further scheme are: the vehicle controller controls the working status of the engine, generator, electronically controlled clutch and electric motor according to the vehicle speed, load size and preset control strategy, and can realize automatic switching of different power drive modes under different working conditions, greatly reducing labor intensity and improving work efficiency.

[0018] Furthermore, the vehicle controller is used to control the operation of the electric motor after the vehicle is started, control the electronically controlled clutch to disconnect, and enter the electric motor direct drive mode; in the electric motor direct drive mode, if the power of the electric energy storage device is less than the power threshold, the engine and the generator are controlled to operate, and the electric energy storage device is charged or the electric motor is powered by the electric coupling device; if the power of the electric energy storage device is greater than the power threshold and the PTO has no power demand, the engine and the generator are controlled not to operate; if the power of the electric energy storage device is greater than the power threshold but the PTO has a power demand, the engine is controlled to operate and the generator is controlled not to operate.

[0019] The beneficial effects of adopting this further solution are: After the vehicle starts, the electric motor is controlled to operate, the electronically controlled clutch is controlled to disengage, and the vehicle enters the direct drive mode. In this mode, the engine and generator are controlled to operate based on the power level of the energy storage device and the PTO power demand. If the engine is not operating, there are zero emissions and no pollution. Even if the engine is operating, it can always operate in the high-efficiency range, thus reducing fuel consumption and emissions overall.

[0020] Furthermore, the vehicle controller is also used to adjust the engine speed in the electric motor direct drive mode, if the load is greater than the load threshold, so that the speed difference between the engine and the electric motor is less than the difference threshold, and then control the electronically controlled clutch to close and enter the engine and electric motor hybrid drive mode. In the engine and electric motor hybrid drive mode, the generator is controlled not to work.

[0021] The beneficial effect of adopting the above further solution is: in the hybrid drive mode of the engine and the electric motor, the tractor power is provided by the engine and the electric motor together, and the power of the whole vehicle is significantly improved.

[0022] Furthermore, the vehicle controller is also used to, in the motor direct drive mode, if the vehicle speed is greater than the vehicle speed threshold, adjust the engine speed so that the speed difference between the engine and the motor is less than the difference threshold, control the electronically controlled clutch to close, and control the motor to stop power output and enter the engine direct drive mode. In the engine direct drive mode, the generator is controlled not to work.

[0023] The beneficial effects of adopting the above-mentioned further solution are: in the engine direct drive mode, there is no efficiency loss caused by power generation and electric drive energy conversion, which can effectively improve the overall transmission efficiency of the tractor and increase the fuel saving rate by 5%-10% compared with the general hybrid system.

[0024] Furthermore, the vehicle controller is also used to control the electric motor to output power and enter the engine and electric motor hybrid drive mode if the load is greater than the load threshold in the engine direct drive mode. In the engine and electric motor hybrid drive mode, the generator is controlled not to work.

[0025] The beneficial effect of adopting the above further solution is: in the engine and electric motor hybrid drive mode, the tractor power is provided by the engine and the electric motor together, which significantly improves the power of the entire vehicle.

[0026] Furthermore, the tractor also includes a battery management system, the vehicle controller is connected to the battery management system, and the battery management system is connected to the electric energy storage device.

[0027] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or may be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A simplified structural diagram of a parallel-parallel hybrid power tractor power system according to an embodiment of the present invention;

[0029] Figure 2 A simplified diagram of the transfer case structure is provided for an embodiment of the present invention;

[0030] Figure 3This is a simplified structural diagram of the tractor power control system provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0031] The following describes the embodiments of the present disclosure through specific concrete examples, and those skilled in the art can easily understand other advantages and effects of the present disclosure from the contents disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all of the embodiments. The present disclosure can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present disclosure. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present disclosure.

[0032] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on this disclosure, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects described herein can be used to implement an apparatus and / or practice a method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this apparatus and / or practice this method.

[0033] Figure 1 A schematic structural diagram of a parallel-parallel hybrid power tractor power system provided in an embodiment of the present invention. Figure 2 The present invention provides a transfer case structure. Figure 1 、 2 As shown, the system includes: an engine 1, a transfer case 2, a generator 11, an electronically controlled clutch 3, an electric motor 8, an electric coupling device 10, an electric energy storage device 9, an AMT gearbox 7, a rear axle 4, wheels 6 and a power take-off device PTO 5.

[0034] The output shaft of the engine 1 is connected to the generator 11 through the main shaft 2-1 of the transfer case 2, the generator 11 is connected to the motor 8 through the electronically controlled clutch 3, the motor 8 is connected to the AMT gearbox 7, and the AMT gearbox 7 is connected to the wheel 6 through the rear axle 4; the generator 11 and the motor 8 are both electrically connected to the electric coupling device 10, and the electric coupling device 10 is electrically connected to the electric energy storage device 9; the main shaft 2-1 and the output shaft 2-3 of the transfer case 2 are connected through a constant meshing gear set 2-2.

[0035] In the above-mentioned parallel-parallel hybrid tractor power system, the travel drive and power output drive are independent of each other and do not affect each other; the AMT only requires two gears (one working gear and one transport gear) and adopts an automatic shifting mechanism, which makes the gearbox structure simple and easy to arrange, and is also easy to automate and remotely control by unmanned driving systems.

[0036] An electronically controlled clutch is added between the generator and the electric motor, enabling flexible switching between multiple modes, including independent engine drive, independent electric motor drive, and combined engine direct drive and electric drive. Electronically controlled clutches include, but are not limited to, dry clutches, wet clutches, electromagnetic clutches, electronically controlled pneumatic clutches, electronically controlled hydraulic clutches, and electronically controlled electric clutches. AMT transmissions automatically shift gears, with the number of gears limited to two.

[0037] In the above embodiment, the travel transmission mechanism of the parallel-parallel hybrid tractor power system transmits power to the rear axle through the engine, generator, electronically controlled clutch, electric motor, and two-speed automatic transmission manual manual gearbox, and outputs power to the wheels through the rear axle; the engine, generator, and electric motor in the travel transmission mechanism are coaxially arranged, and the generator and electric motor can achieve power coupling through the electronically controlled clutch; and the power transmission routes of the travel mechanism and the power output device are independent of each other and do not interfere with each other. The present invention can provide different power drive modes under different operating conditions, improve the power economy of the tractor and reduce pollution emissions; it can simultaneously meet the vehicle speed, torque, and traction requirements under various operating conditions; and the power system does not require a complex gearbox, occupies a small space, and is conducive to the overall vehicle layout.

[0038] Figure 3 This is a simplified structural diagram of the tractor power control system provided by an embodiment of the present invention. Figure 3As shown, the tractor including the parallel-parallel hybrid power tractor power system provided by the above embodiment includes a vehicle controller, an engine controller, a generator controller and a motor controller, and also includes the parallel-parallel hybrid power tractor power system described in the above technical solution; the vehicle controller is electrically connected to the engine controller, the generator controller, the motor controller, the electronically controlled clutch and the AMT gearbox; the engine controller is electrically connected to the engine, the generator controller is electrically connected to the generator, and the motor controller is electrically connected to the motor.

[0039] Optionally, the tractor further includes a battery management system, the vehicle controller is connected to the battery management system, and the battery management system is connected to the electric energy storage device. The electric energy storage device is a storage battery or a power battery.

[0040] The vehicle controller obtains the vehicle speed and load size, and controls the working status of the engine, generator, electronically controlled clutch and electric motor according to the vehicle speed, load size and preset control strategy, thereby realizing automatic switching of different power drive modes under different working conditions.

[0041] Specifically, after the vehicle is started, the vehicle controller controls the motor 8 to work, controls the electronically controlled clutch 3 to disconnect, and enters the motor direct drive mode. The power generated by the motor 8 is transmitted to the wheels 6 through the AMT gearbox 7 and the rear axle 4 to drive the tractor. If the power of the electric energy storage device 9 is less than the power threshold, the engine 1 and the generator 11 are controlled to work, and the electric energy storage device 9 is charged or the electric motor 8 is powered by the electric coupling device 10. If the power of the electric energy storage device 9 is greater than the power threshold and the PTO has no power demand, the engine 1 and the generator 11 are controlled not to work. If the power of the electric energy storage device is greater than the power threshold but the PTO has a power demand, the engine 1 is controlled to work and the generator 11 is controlled not to work.

[0042] In direct motor drive mode, if the load exceeds a load threshold, the engine 1 speed is adjusted until the speed difference between the engine 1 and the motor 8 is less than the difference threshold. The electronically controlled clutch 3 is then closed, and the tractor enters hybrid engine and motor drive mode. In hybrid engine and motor drive mode, the generator 11 is controlled to not generate power. In hybrid drive mode, the power output of the engine 1 through the main shaft of the transfer case 2 is coupled with the power output of the motor 3. This coupled power is then transmitted to the wheels 6 via the AMT transmission 7 and rear axle 4 to drive the tractor for both driving and towing operations.

[0043] In direct-drive mode, if the vehicle speed exceeds a threshold, the engine 1 speed is adjusted to ensure that the speed difference between the engine and motor 8 is less than the threshold. The electronically controlled clutch 3 is then closed, and the motor 8 is stopped from outputting power, entering direct-drive mode. In direct-drive mode, the generator 11 is deactivated. With motor 8 discontinued, power to the AMT transmission 7 and rear axle 4 is provided solely by the engine 8, enabling the engine 8 to directly drive the tractor for both driving and towing operations.

[0044] In engine direct drive mode, if the load exceeds the load threshold, the motor 8 is controlled to output power, entering the engine and motor hybrid drive mode. In this hybrid drive mode, the generator 11 is controlled to be inoperative. In hybrid drive mode, the power output of the engine 1 through the main shaft of the transfer case 2 is coupled with the power output of the motor 3. The coupled power is transmitted to the wheels 6 through the automatic transmission (AMT) transmission 7 and the rear axle 4 to drive the tractor for driving and towing operations.

[0045] In the above-mentioned driving modes, the output shaft 2-3 of the transfer case 2 can directly take power from the engine 1, and then be connected to the rear axle 4, and output power to the power take-off device (PTO) 5 through the rear axle; the traveling mechanism transmits power to the rear axle 4 through the engine 1, the generator 11, the electronically controlled clutch 3, the electric motor 8, and the two-speed AMT gearbox 7, and outputs power to the wheels 6 through the rear axle, and the power transmission route of the power take-off device (PTO) 5 is independent of each other and does not interfere with each other.

[0046] The aforementioned parallel-parallel hybrid system can improve tractor power economy and reduce pollution emissions. At the same time, the unique engine direct drive mode eliminates the efficiency losses caused by power generation and electric drive energy conversion, effectively improving the tractor's overall rotational efficiency and increasing fuel savings by 5%-10% compared to conventional hybrid systems. It achieves infinitely variable speeds across all tractor operating conditions, significantly reducing labor intensity and improving operating efficiency. The electric drive system is integrated with the engine and transmission system, providing multiple operating modes, enabling a single tractor to handle more complex operating conditions. The AMT requires only two gears (one operating gear and one transport gear) and utilizes an automatic shift mechanism, making the transmission structure simple and easy to deploy, while also facilitating automated control and remote control by unmanned systems.

[0047] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A parallel-parallel hybrid tractor power system, characterized in that: include: Engine (1), transfer case (2), generator (11), electronically controlled clutch (3), electric motor (8), electric coupling device (10), electric energy storage device (9), AMT gearbox (7), rear axle (4), wheels (6) and power take-off device PTO (5); The output shaft of the engine (1) is connected to the generator (11) through the main shaft (2-1) of the transfer case (2), the generator (11) is connected to the electric motor (8) through the electronically controlled clutch (3), the electric motor (8) is connected to the automatic transmission mechanism (AMT) gearbox (7), and the AMT gearbox (7) is connected to the wheels (6) through the rear axle (4); the generator (11) and the electric motor (8) are both electrically connected to the electric coupling device (10), and the electric coupling device (10) is electrically connected to the electric energy storage device (9); The output shaft (2-3) of the transfer case (2) is connected to a power take-off device (PTO) (5) via the rear axle (4); the main shaft (2-1) and the output shaft (2-3) of the transfer case (2) are connected in a gearing transmission via a constant meshing gear set (2-2); After the vehicle is started, the vehicle controller controls the motor (8) to operate, controls the electronically controlled clutch (3) to disconnect, and enters the motor direct drive mode; the power generated by the motor (8) is transmitted to the wheels (6) through the AMT gearbox (7) and the rear axle (4) to drive the tractor to travel; if the power of the electric energy storage device (9) is less than the power threshold, the engine (1) and the generator (11) are controlled to operate, and the electric energy storage device (9) is charged or the motor (8) is powered by the electric coupling device (10); if the power of the electric energy storage device (9) is greater than the power threshold and the PTO has no power demand, the engine (1) and the generator (11) are controlled not to operate; if the power of the electric energy storage device is greater than the power threshold but the PTO has a power demand, the engine (1) is controlled to operate and the generator (11) is controlled not to operate; In the motor direct drive mode, if the load is greater than the load threshold, the speed of the engine (1) is adjusted so that the speed difference between the engine (1) and the motor (8) is less than the difference threshold, and the electronically controlled clutch (3) is controlled to close, thereby entering the engine and motor hybrid drive mode; in the engine and motor hybrid drive mode, the generator (11) is controlled not to generate electricity; in the hybrid drive mode, the power output by the engine (1) through the main shaft of the transfer case (2) is coupled with the power output by the motor (1), and the coupled power is transmitted to the wheels (6) through the AMT gearbox (7) and the rear axle (4) to drive the tractor for travel and towing operations; In the motor direct drive mode, if the vehicle speed is greater than the vehicle speed threshold, the engine (1) speed is adjusted so that the speed difference between the engine and the motor (8) is less than the difference threshold, the electronically controlled clutch (3) is controlled to close, and the motor (8) is controlled to stop power output, entering the engine direct drive mode; in the engine direct drive mode, the generator (11) is controlled not to work; in the engine direct drive mode, the motor (8) stops power output, and the power transmitted to the AMT gearbox (7) and the rear axle (4) is provided only by the motor (8), so that the motor (8) directly drives the tractor to travel and tow. In the engine direct drive mode, if the load is greater than the load threshold, the electric motor (8) is controlled to output power, and the engine and electric motor hybrid drive mode is entered; in the engine and electric motor hybrid drive mode, the generator (11) is controlled not to work; in the hybrid drive mode, the power output by the engine (1) through the main shaft of the transfer case (2) is coupled with the power output by the electric motor (8), and the coupled power is transmitted to the wheels (6) through the AMT gearbox (7) and the rear axle (4) to drive the tractor for travel and towing operations.

2. The system according to claim 1, wherein: The electronically controlled clutch (3) is a dry clutch, a wet clutch, an electromagnetic clutch, an electronically controlled pneumatic clutch, an electronically controlled hydraulic clutch or an electronically controlled electric clutch.

3. The system according to claim 1 or 2, characterized in that The AMT gearbox (7) adopts a two-speed AMT gearbox.

4. A tractor, characterized in that: It includes a vehicle controller, an engine controller, a generator controller and a motor controller, and also includes the parallel-parallel hybrid power tractor power system according to any one of claims 1 to 3; the vehicle controller is electrically connected to the engine controller, generator controller, motor controller, electronically controlled clutch and AMT gearbox.

5. The tractor according to claim 4, characterized in that: The vehicle controller is used to obtain the vehicle speed and load size, and controls the working states of the engine (1), generator (11), electronically controlled clutch (3) and electric motor (8) according to the vehicle speed, load size and preset control strategy, thereby realizing automatic switching of different power drive modes under different working conditions.

6. The tractor according to claim 4 or 5, characterized in that: It also includes a battery management system, the vehicle controller is connected to the battery management system, and the battery management system is connected to the electric energy storage device (9).

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