A hybrid electric continuously variable power drive system, method and tractor

Abstract

The present disclosure relates to the technical field of vehicle power devices, and provides a hybrid electric continuously variable power drive system, method and tractor, including: a generator, a mechanical coupling device, a motor drive unit and a reversible auxiliary motor connected in sequence; the engine is connected to the auxiliary motor through the mechanical coupling device to supply electric energy to the motor drive unit; the power output ends of multiple motors of the motor drive unit are connected to the mechanical coupling device, and the power of the multiple motors, the auxiliary motor and the engine is coupled and output through the mechanical coupling device to drive the wheels. Through the improvement of the structure of the power drive system, the present disclosure proposes a flexible cooperative control scheme for the engine and the motor, which can effectively solve the problems of power mismatch and low efficiency existing in the prior art, ensure the efficient operation of the tractor under different working conditions, and improve the stability, reliability and overall performance of the system.

Description

Technical Field

[0001] The present disclosure relates to the technical field of vehicle power devices, and more specifically, to a hybrid electric continuously variable transmission power drive system, method, and tractor. Background Art

[0002] The statements in this section merely provide background technical information related to the present disclosure and do not necessarily constitute prior art.

[0003] During the operation of a tractor, it is affected by various factors, such as the contact area between the tires and the soil, soil humidity, soil viscosity, operation depth, and the working state of agricultural implements. These factors cause complex non-linear dynamic changes in the resistance between the agricultural implement and the land. Since these changes not only fluctuate over time but are also significantly affected by environmental conditions, traditional transmission systems often cannot efficiently cope with such changes, resulting in unstable working performance and low efficiency. Tractor shifting technologies generally include traditional mechanical shifting technologies (such as sliding gear shifting, dog clutch and synchronizer shifting) and continuously variable transmission technologies (such as hydraulic continuously variable transmission technology). Traditional mechanical shifting technologies are usually manually operated and do not fully consider the working state and operation environment of the tractor, thus leading to problems such as unsmooth shifting, high noise, and poor reliability. In addition, mechanical shifting also has disadvantages such as complex structure and inconvenient operation.

[0004] Continuously variable transmission technology has improved the disadvantages of traditional mechanical shifting to a certain extent. In particular, a hydraulic continuously variable transmission (CVT) can provide a smooth shifting experience. However, the efficiency of the hydraulic transmission system is low, and there are problems such as complex structure, troublesome maintenance, and energy loss in the hydraulic part. Therefore, although hydraulic continuously variable transmission technology has certain advantages, there is still room for optimization. Compared with the hydraulic system, the electric motor-driven continuously variable transmission technology (ECVT) has higher efficiency and lower maintenance costs. The ECVT technology realizes continuously variable transmission by adjusting the opening and closing of the electromagnetic clutch through an electronic control system. This method is smoother than traditional mechanical shifting and hydraulic systems and does not require complex mechanical components such as gears, clutches, or torque converters, so it has higher reliability and lower energy loss.

[0005] However, the existing motor-driven continuously variable transmission technology still faces some challenges. Limited by the structure of the power drive system, the current power distribution method mainly relies on fixed power distribution strategies, which are difficult to flexibly adjust according to the actual working conditions and also require a large battery capacity. Under high load conditions, the power output of the tractor power system may be insufficient. Especially when the tractor faces complex working environments such as different soil types, humidity changes, and terrain undulations, the power demand fluctuates violently, and the existing solutions may not be able to adjust the output in time, affecting the operation efficiency. The traditional power distribution mechanism cannot accurately handle complex working scenarios, resulting in uneven power. Especially in the starting, accelerating, and steering links, the coordinated operation of the motor and the engine may lag or mismatch, affecting the operation stability and power response speed of the tractor. Summary of the Invention

[0006] To solve the above problems, the present disclosure proposes a hybrid electric control continuously variable transmission power drive system, method, and tractor. Through the improvement of the power drive system structure, a flexible coordinated control scheme for the engine and the motor is proposed, which can effectively solve the problems of power mismatch and low efficiency in the existing technology, ensure the high-efficiency operation of the tractor under different working conditions, and improve the stability, reliability, and overall performance of the power system.

[0007] To achieve the above object, the present disclosure adopts the following technical solutions:

[0008] One or more embodiments provide a hybrid electric control continuously variable transmission power drive system, including: a generator, a mechanical coupling device, a motor drive unit, and a reversible auxiliary motor connected in sequence;

[0009] The engine is connected to the auxiliary motor through the mechanical coupling device to supply electrical energy to the motor drive unit; the power output ends of the multiple motors of the motor drive unit are connected to the mechanical coupling device, and the mechanical coupling device couples and outputs the power of the multiple motors, the auxiliary motor, and the engine to drive the wheels.

[0010] Based on the above-mentioned drive control method for a hybrid electric control continuously variable transmission power drive system, the following steps are included:

[0011] Obtain the vehicle operation instruction. When starting the vehicle, enter the electric mode;

[0012] When the vehicle is in the working state and receives the PTO power output instruction, output the rotary tillage power through the motor; if the wheel power output requirement is less than the set threshold, enter the engine drive and charging mode, and provide the driving force for the wheels through the engine; otherwise, enter the coordinated working mode, and provide power for the wheels through the coordinated control of the engine and the motor;

[0013] When the vehicle is in the engine operating state, in response to the charging request of the battery, it switches to the engine operating mode to charge the battery.

[0014] A tractor adopts the above-mentioned hybrid electric control continuously variable transmission power drive system to provide power for the operation of the tractor and the wheels.

[0015] Compared with the prior art, the beneficial effects of the present disclosure are as follows:

[0016] In the present disclosure, through the mechanical coupling device and the auxiliary motor, the power of the engine is divided into two parts: power generation and driving, enabling the system to optimize energy utilization under different working conditions and improve fuel economy. The system is provided with multiple motors, auxiliary motors and engines, and the driving force source of the tractor is no longer single, but is dynamically provided by multiple power sources in cooperation. It can intelligently adjust the power output according to different operation requirements, achieve higher driving control accuracy, and improve the flexibility of the system power regulation.

[0017] The driving control method proposed in the present disclosure controls the cooperation between the motor and the engine through precise working mode switching, can flexibly adjust the power output under different working conditions, and ensure power balance and efficient utilization. By real-time monitoring the vehicle load and battery power, this method can ensure that the system responds quickly and provides a stable power output under complex working conditions, avoiding the lag and instability phenomena that may occur in the traditional system.

[0018] The advantages of the present disclosure and the advantages of additional aspects will be described in detail in the following specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The specification drawings forming a part of the present disclosure are used to provide a further understanding of the present disclosure. The schematic embodiments of the present disclosure and their descriptions are used to explain the present disclosure and do not constitute a limitation to the present disclosure.

[0020] Figure 1 is a schematic structural diagram of the power drive system of Embodiment 1 of the present disclosure;

[0021] Figure 2 is a flowchart of the power drive method of Embodiment 2 of the present disclosure;

[0022] Wherein: 1. First motor, 2. Second motor, 3. Auxiliary motor, 4. First power battery, 5. Second power battery, 6. First gear;

[0023] 7. Mechanical coupling device, 71. Ring gear, 72. Second sun gear, 73. First sun gear, 74. Second planetary gear, 75. First planetary gear, 76. Planet carrier;

[0024] 8. Second gear, 9. Third gear, 10. Fourth gear, 11. Fifth gear. Detailed implementation mode

[0025] The present disclosure will be further described below in conjunction with the accompanying drawings and embodiments.

[0026] It should be noted that the following detailed description is exemplary and is intended to provide further illustration of the present disclosure. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present disclosure belongs.

[0027] It should be noted that the terms used herein are only for describing specific implementation modes and are not intended to limit the exemplary implementation modes according to the present disclosure. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof. It should be noted that, without conflict, the various embodiments and features in the present disclosure can be combined with each other. The embodiments will be described in detail below with reference to the accompanying drawings.

[0028] Embodiment 1

[0029] In the technical solutions disclosed in one or more embodiments, as Figure 1 shown, a hybrid electric continuously variable power drive system includes: an engine (Engine), a mechanical coupling device 7, a motor drive unit, and an auxiliary motor 3 that can rotate forward and backward, which are connected in sequence;

[0030] The engine is connected to the auxiliary motor 3 through the mechanical coupling device 7 to supply electrical energy to the motor drive unit; the power output ends of the multiple motors of the motor drive unit are connected to the mechanical coupling device 7, and the mechanical coupling device 7 couples and outputs the power of the multiple motors, the auxiliary motor 3, and the engine as the driving force of the wheels to achieve continuously variable speed of the vehicle;

[0031] In this embodiment, through the mechanical coupling device 7 and the auxiliary motor 3, the power of the engine is divided into two parts: power generation and driving, so that the system can optimize energy utilization under different working conditions and improve fuel economy. The system is provided with multiple motors, an auxiliary motor 3, and an engine. The driving force source of the tractor is no longer single, but is dynamically provided by multiple power sources in cooperation, and the power output can be intelligently adjusted according to different operation requirements, achieving higher driving control accuracy and improving the flexibility of the system power regulation.

[0032] In this embodiment, an auxiliary motor 3 is provided to output the kinetic energy of the engine to the motor drive system, which can realize the optimized distribution of the engine's output power and improve the utilization rate. At the same time, when the auxiliary motor 3 can reverse, it can be used as a motor to provide driving power for the gears. In this way, the driving force sources for wheel drive can include multiple motors, the auxiliary motor 3, and the engine, improving the flexibility of driving force regulation, enabling fine-grained driving force adjustment, and enabling stepless speed change within a wide range. Through the precise coordinated operation of the main components, efficient stepless speed change drive and external device drive functions are realized.

[0033] Furthermore, in the motor drive unit, the power output end of at least one motor is connected to a power take-off (PTO) shaft, and the PTO is used to transmit power to external devices, such as agricultural implements, to ensure the efficient operation of the tractor during work.

[0034] Optionally, one or more motors of the motor drive unit are connected to the power output shaft (PTO) of the working component through a clutch CPTO;

[0035] In some embodiments, when the auxiliary motor 3 rotates forward, it generates electricity to convert the kinetic energy output by the engine into electrical energy; when the auxiliary motor 3 rotates in reverse, it acts as a motor to transmit the kinetic energy to the mechanical coupling device 7 for auxiliary drive.

[0036] Specifically, the power shaft of the auxiliary motor 3 is connected to the planet carrier 76 of the mechanical coupling device 7 through a second gear 8;

[0037] In some embodiments, the motor drive unit may include multiple parallel drive branches, and each drive branch includes a power battery and a motor connected in series; the power battery is connected to the electrical energy output end of the auxiliary motor 3 to receive the electrical energy of the auxiliary motor 3; the output ends of each motor are provided with clutches, and the clutches connected to each motor are cascaded and then connected to an input end of the mechanical coupling device 7 through a first gear 6;

[0038] The setting of the drive branches can be set as needed. Preferably, as Figure 1 shown, two drive branches are set in this embodiment: the first drive branch includes a first power battery 4 and a first motor 1 connected in series, and a clutch CMotor2 is provided at the output end of the first motor 1; the second drive branch includes a second power battery 5 and a second motor 2 connected in series, and a clutch CMotor1 is provided at the output end of the second motor 2. The output ends of the clutch CMotor2 and the clutch CMotor1 are connected by gear meshing to achieve cascading, and the output powers of the two motors are superimposed and coupled, and are transmitted to the mechanical coupling device 7 through the first gear 6;

[0039] The auxiliary motor 3 serves as an auxiliary electric motor, providing electrical energy to the power battery of the motor drive unit in the charging mode; in the combined drive mode, the first motor 1 and the second motor 2 jointly provide power to the wheels to achieve stepless speed change. The first power battery 4 and the second power battery 5 are responsible for providing the required power for the motor and charging and discharging according to different working modes to ensure the continuous operation of the system.

[0040] In some embodiments, the mechanical coupling device 7 adopts a planetary gear mechanism, such as Figure 1 shown, the planetary gear mechanism includes a large ring gear 71, a first sun gear 73, a first planet gear 75, a second sun gear 72, a second planet gear 74 and a planet carrier 76; the second sun gear 72, the second planet gear 74 and the planet carrier 76 are connected in sequence; the first sun gear 73, the first planet gear 75 and the planet carrier 76 are connected in sequence; the first sun gear 73 and the large ring gear 71 are respectively connected to the power output end of the engine through a clutch structure; the second sun gear 72 is connected to the power output end of the motor drive unit;

[0041] Specifically, in this embodiment, the second sun gear 72 is connected to the output end of the clutch CMotor1 of the motor drive unit through a first gear 6.

[0042] When in use, if the motor drive unit is used for driving, the clutch CMotor2 at the output end of the first motor 1 is engaged, the clutch CMotor1 at the output end of the second motor 2 is engaged, the power output ends of the clutch CMotor2 and the clutch CMotor1 are connected, and then the powers of the two motors are superimposed and transmitted to the second sun gear 72 through the first gear 6, and then output to the driving wheels through the second planet gear 74 and the planet carrier 76; when one of the motors outputs power, the power is directly transmitted to the first gear 6 through the corresponding clutch;

[0043] If the engine is used for driving, the power output end of the engine transmits power to the first planet gear 75 through the first sun gear 73 and outputs power through the planet carrier 76; or / and, transmits power to the first planet gear 75 through the large ring gear 71 and outputs power through the planet carrier 76;

[0044] The planetary gear mechanism of this embodiment ensures smooth power transmission by precisely matching the gears and distributing the input power to each gear component through the relative movement between the planet carrier 76 and the sun gear. Through this structure, the system can achieve stepless speed change and efficient power distribution to meet the needs of tractors or other machinery in various working environments.

[0045] In a further technical solution, a clutch structure is provided at the power output end of the engine (Engine), which is connected between the engine (Engine) and the mechanical coupling device 7;

[0046] The clutch structure includes clutches C1, C2, and C3; clutch C1 and clutch C2 are successively connected to the power output shaft of the engine; clutch C3 is connected to the power output end of the engine through the third gear 9; clutch C3 and clutch C1 are connected to the first sun gear 73 through the fourth gear 10; clutch C2 is connected to the large ring gear 71 of the planetary gear mechanism through the fifth gear 11;

[0047] When clutch C1 engages or / and clutch C3 engages, the power of the engine is transmitted via the fourth gear 10 and finally transmitted to the first sun gear 73 of the planetary gear mechanism to achieve specific power splitting or speed regulation;

[0048] When clutch C2 engages, the power of the engine passes through the fifth gear 11 and is connected to the large ring gear 71 of the planetary gear mechanism, entering the transmission system through different gear paths to adapt to different working condition requirements;

[0049] Furthermore, a lock LOCK2 is provided at the power output end of the fourth gear 10, which can lock the gear assembly under specific circumstances to optimize the power transmission efficiency or achieve different drive mode switches;

[0050] Furthermore, a lock LOCK1 is provided outside the large ring gear 71 of the planetary gear mechanism, which is used to fix the large ring gear 71 under specific circumstances, thereby changing the transmission mode of the planetary gear mechanism to optimize the power output or achieve different drive modes;

[0051] In a further technical solution, interlocking control of lock LOCK2 and lock LOCK1 can achieve the output of different power ranges of the engine. When lock LOCK2 is locked, lock LOCK1 is disconnected; when lock LOCK2 is disconnected, lock LOCK1 is locked; both lock LOCK1 and lock LOCK2 are disconnected.

[0052] In this embodiment, the power output of the engine can be adjusted to the corresponding set range through interlocking control. Through the two locks, the power output of multiple different power ranges can be achieved, improving the flexibility of power output regulation.

[0053] During the speed change process, clutches C1, C2, and C3 are adjusted according to different gears to achieve the continuously variable transmission function under various working conditions. Locks LOCK1 and LOCK2 respectively control the large ring gear 71 and the sun gear in the planetary gear mechanism to ensure that the power can be normally output. Through the precise cooperation of the planetary gear mechanism, the motor and the engine can flexibly adjust the power output of the wheels when working together to achieve continuously variable transmission drive.

[0054] The power output structure connected to the rear end of the planet carrier 76 provides power for the wheels. The motive output structure includes multiple gear pairs, which are transmission-connected to the CVT Out end of the drive shaft of the wheels through the gear pairs. In the figure, DR (Drive Reverse) and DF (Drive Forward) respectively represent the reverse gear (reverse drive) and forward gear (forward drive) of the transmission system.

[0055] The above-mentioned hybrid electric continuously variable transmission power drive system can achieve multiple working modes, as shown in Table 1, including the following working modes:

[0056] (1) Working mode 1: Engine drive and charging mode. The engine works to provide charging electric energy and driving force for the wheels, and the vehicle operation provides driving force through the motor of the motor drive unit.

[0057] In this mode, the power of the engine can not only drive the wheels but also charge, thus optimizing energy utilization and improving the operation sustainability and fuel economy of the tractor.

[0058] According to the different gears of the engine, control the lock 1 or lock 2 to disconnect, so that the engine controls the wheels alone through the planetary gear mechanism, and at the same time drives the auxiliary motor 3 to generate electricity. When the power stored in the power battery is lower than the threshold, store the power in the first power battery 4 and the second power battery 5 to prepare for driving the first motor 1 and the second motor 2.

[0059] If the tractor has an operation requirement, the clutch CPTO is engaged, and the first power battery 4 supplies power to the first motor 1 to do work outward through the power take-off shaft (PTO).

[0060] This mode is equivalent to only the engine outputting power outward, and is suitable for the situation where the power battery has insufficient stored power after the tractor completes the operation and needs to be charged, or for the operation in a flat area with low power demand for flat driving.

[0061] In this mode, the two-way power transmission of the engine is achieved through mechanical connection, enabling the two working functions of power generation and traction to work in coordination, thereby optimizing the energy usage efficiency and enhancing the power stability during operation. According to the gear position, the output adjustment of different power ranges of the engine is realized through the selective engagement of LOCK1 or LOCK2, achieving precise control of the wheels under different working conditions. When the soil humidity, viscosity, or load changes, the tractor can rely on the engine to directly drive the wheels while adjusting the power distribution to optimize fuel consumption. The engine is not only used for traction but also for power generation, efficiently utilizing the surplus power to reduce fuel waste. Through the two-way power transmission, it ensures that the engine operates under the best working conditions, improving the economy of the overall system and enabling charging while working, avoiding operation interruption caused by battery power depletion. This mode allows the tractor to mainly rely on the engine for driving and charging under light load or on flat terrain, and rely on the battery for assistance in complex terrains to improve operation stability.

[0062] (2)Working Mode 2: Cooperative Working Mode. The engine works and the motor drive unit works. The output power of the engine and the motor is cooperatively controlled according to the wheel load demand; through reasonable power distribution and control, the system realizes the combined operation of the engine and multiple motors to meet the various operation requirements of the tractor in complex environments;

[0063] In this mode, the power output of the engine and the power output of the motor are adjusted according to different loads to realize the combined operation of the motor and the engine, and the following cooperative working states are achieved through control;

[0064] 2.1) The clutch CMotor1 and the clutch CPTO are engaged, and both the lock LOCK1 and the lock LOCK2 are disengaged. The first motor 1 provides power to the power take-off shaft (PTO), and the second motor 2 and the engine are power-coupled through the planetary gear mechanism and jointly provide power to the wheels, enabling the tractor to achieve stepless speed change;

[0065] 2.2) The clutch CMotor2, the clutch CMotor1, and the clutch CPTO are all engaged, and both the lock LOCK1 and the lock LOCK2 are disengaged. The first motor 1 provides power to the power take-off shaft (PTO), and the first motor 1, the second motor 2, and the engine are power-coupled through the planetary gear mechanism and jointly provide power to the wheels, enabling the tractor to achieve stepless speed change;

[0066] In this cooperative working state, the first motor 1 can provide power to the wheels, avoiding the first motor 1 entering the idle state when the PTO is not working.

[0067] 2.3) When the system workload is different, it is possible to select to adjust the power output of the engine according to the selection of the clutch gear;

[0068] 2.4) Drive the working state of the auxiliary motor 3 according to the battery power. If charging is required, control the auxiliary motor 3 to rotate forward to charge the power battery. When charging is not required, the auxiliary motor 3 can rotate reversely to provide assistance to the planet carrier 76 in the planetary gear mechanism, which is also equivalent to indirectly supplying energy to the wheels.

[0069] In this mode, through the precise cooperation of the engine and the motor, while providing stable power, it ensures the rational use of energy, making the operation of the tractor more efficient and stable in complex environments, and at the same time enhancing the adaptability of the system and the overall operation efficiency. The engine and the three motors jointly drive, and can provide flexible and sufficient power under different workloads to ensure the operation stability of the tractor in complex environments. Through the coordinated work of the engine and the motor, the system can flexibly distribute power to adapt to different working scenarios. The auxiliary motor 3 can reverse and convert the electric energy already stored in the battery into mechanical energy to drive the planet carrier 76 to participate in the power output; the dual functions of the generator ensure that power can be provided efficiently when needed, and at the same time, it can also charge the battery without affecting the operation efficiency. Under low load conditions, the motor can provide additional acceleration force; when starting or the instantaneous load is large, the motor can provide high torque output; while the engine can provide stable traction force to adapt to relatively continuous power requirements. Through the cooperation of the engine and the motor, precise power distribution is achieved, improving the energy utilization efficiency and the operation efficiency. The system can intelligently adjust to reduce fuel waste and at the same time improve the battery usage efficiency to ensure that the tractor can still operate continuously under complex working conditions.

[0070] (3) Working mode three: Electric mode. In this mode, the engine completely stops working, and the movement of the tractor completely depends on the power provided by the motor drive unit;

[0071] In this mode, the engine does not work, and both the lock LOCK1 and the lock LOCK2 are in the locked state; the clutch CPTO is disengaged; control the second motor 2 and the auxiliary motor 3 to work, and the clutch CMotor1 is engaged, which can effectively transmit the power of the second motor 2 and the auxiliary motor 3 to the wheels;

[0072] The power output of the auxiliary motor 3 acts on the planet carrier 76 of the planetary gear mechanism to play an assisting role; the clutch CPTO is disengaged;

[0073] In this mode, the power source of the tractor comes entirely from the electrical energy in the battery, which is suitable for starting or short-term low-power operation. The fuel economy of the engine during cold start is poor, and the electric motor can provide efficient and instantaneous torque output, especially suitable for the occasions of tractor starting and low-speed driving. The acceleration performance of the tractor relying on the engine to start is significantly inferior to that driven by the electric motor. Relying entirely on the electric motor when starting can reduce emissions and quickly reach the predetermined speed. Therefore, generally, the PTO does not need to operate when the tractor is just started. In this mode, the first electric motor 1 does not need to operate, the clutch CPTO is disengaged, and the clutch CMotor2 is also disengaged. The power of the first power battery 4 is basically supplied to the second electric motor 2 and the auxiliary motor 3.

[0074] In the electric mode, since the engine stops working completely and only relies on the electric motor for driving, the emissions of the tractor are reduced, meeting the environmental protection requirements, and it operates with low noise during the operation process, which is suitable for the occasions where environmental pollution and noise need to be reduced. By completely eliminating the fuel consumption of the engine, zero-emission operation is achieved, which is very suitable for high-environmental-protection-requirement operation scenarios, such as indoor operations or operation environments near cities. When the battery is fully charged, the electric motor provides a stable and continuous power output, maximizing the utilization of the battery's electrical energy and reducing energy waste. The electric mode is suitable for the occasions of tractor starting, low-speed driving, and low-load operations, especially for cold start and short-term low-power operation occasions, and can provide a faster response and efficient power output.

[0075] Table 1 Component operation conditions under each working mode;

[0076]

[0077] This embodiment provides a multi-mode working method for the hybrid power system, including engine drive and power generation, combined drive of the engine and the electric motor, and separate drive of the electric motor; enabling the tractor to flexibly adjust according to different operation environments and requirements. Whether it is heavy-load tillage or low-speed and fine operations, the system can provide the most suitable power support, enhancing the adaptability of the tractor, improving the working efficiency and operation convenience. At the same time, efficient energy utilization can be achieved in various working modes, enhancing the overall efficiency of the system.

[0078] Embodiment 2

[0079] Based on Embodiment 1, this embodiment provides a drive control method for a hybrid electric continuously variable power drive system described in Embodiment 1, as Figure 2 shown, including the following steps;

[0080] Step 1: Obtain the vehicle operation instruction. When starting the vehicle, enter the electric mode;

[0081] Step 2: When the vehicle is in the working state and receives a PTO power output instruction, the motor outputs rotary tillage power; if the wheel power output requirement is less than the set threshold, enter the engine drive and charging mode, and the engine provides the driving force for the wheels; otherwise, enter the cooperative working mode, and the engine and the motor cooperate to control to provide power for the wheels.

[0082] Step 3: When the vehicle is in the engine working state and in response to the charging request of the battery, switch to the engine running mode to charge the battery.

[0083] The traditional power distribution mechanism cannot accurately handle complex operating scenarios, resulting in unbalanced power, especially in links such as starting, accelerating, and steering. The cooperative work between the motor and the engine may be lagged or mismatched, affecting the operating stability and power response speed of the tractor. To address this problem, the drive control method proposed in this embodiment controls the cooperative work between the motor and the engine through precise working mode switching, can flexibly adjust the power output under different working conditions, and ensure balanced and efficient use of power. By real-time monitoring of the vehicle load and battery power, this method can ensure that the system responds quickly and provides stable power output under complex working conditions, avoiding the lag and instability phenomena that may occur in the traditional system.

[0084] In Step 1, the electric mode is Working Mode 3. In this mode, the engine stops working, and both the locking device LOCK1 and the locking device LOCK2 are in the locked state; the clutch CPTO is disengaged; control the second motor 2 and the auxiliary motor 3 to work, the clutch CMotor1 is engaged, the clutch CMotor2 is disengaged, and the power of the second motor 2 and the auxiliary motor 3 is coupled and transmitted to the wheels.

[0085] In Step 2, the engine drive and charging mode is Working Mode 1. According to the different engine gears, control the locking device LOCK1 or the locking device LOCK2 to disengage, so that the engine drives the wheels alone through the planetary gear mechanism, and at the same time drives the auxiliary motor 3 to generate electricity. When the power stored in the power battery is lower than the threshold, the power is stored in the first power battery 4 and the second power battery 5.

[0086] If there is an operation requirement and a PTO power output instruction is received, the clutch CPTO is engaged, the first power battery 4 supplies power to the first motor 1, and work is done outward through the power take-off shaft (PTO).

[0087] In Step 2, when the wheel power output requirement is less than the set threshold, that is, the vehicle is in a relatively flat operating area, the operation can be realized through the independent energy supply of the engine.

[0088] In Step 2, when entering the cooperative working mode, according to different wheel loads, the engine and the motor are cooperatively controlled to jointly provide power for the wheels. Specifically:

[0089] Step 21: Set a first wheel load threshold range and a second wheel load threshold range that increase in sequence.

[0090] Optionally, the first wheel load threshold range can be set to 0 to A, and the second wheel load threshold range can be set to greater than A, where A is a set load threshold.

[0091] Step 22: Obtain the wheel load. When within the first wheel load threshold range, control the clutch CMotor1 and the clutch CPTO to engage, and both the lock LOCK1 and the lock LOCK2 to disconnect. The first motor 1 provides power to the power take-off shaft (PTO), and the second motor 2 and the engine are power-coupled through the planetary gear mechanism and jointly provide power to the wheels.

[0092] Step 23: When the wheel load is within the second wheel load threshold range, the clutch CMotor2, the clutch CMotor1, and the clutch CPTO are all engaged, and both the lock LOCK1 and the lock LOCK2 are disconnected. The first motor 1 provides power to the power take-off shaft (PTO), and the first motor 1, the second motor 2, and the engine are power-coupled through the planetary gear mechanism and jointly provide power to the wheels.

[0093] Furthermore, in the cooperative working mode, according to the battery power, drive the working state of the auxiliary motor 3. If charging is required, control the auxiliary motor 3 to rotate forward to charge the power battery. When charging is not required, the auxiliary motor 3 can rotate in reverse to provide assistance to the planet carrier in the planetary gear mechanism, which is also equivalent to indirectly supplying energy to the wheels.

[0094] Embodiment 3

[0095] Based on Embodiment 1, this embodiment provides a tractor that uses a hybrid electric continuously variable power drive system described in Embodiment 1 to provide power for the operation of the tractor and the wheels.

[0096] The above are only the preferred embodiments of the present disclosure and are not used to limit the present disclosure. For those skilled in the art, various changes and modifications can be made to the present disclosure. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present disclosure shall be included within the protection scope of the present disclosure.

[0097] Although the specific embodiments of the present disclosure have been described above in conjunction with the accompanying drawings, they are not intended to limit the scope of protection of the present disclosure. Those skilled in the art should understand that, based on the technical solutions of the present disclosure, various modifications or variations that can be made by those skilled in the art without creative efforts are still within the scope of protection of the present disclosure.

Claims

1. A hybrid electric continuously variable power drive system, characterized in that, Comprising: An engine, a mechanical coupling device, an electric motor drive unit, and an auxiliary motor capable of forward and reverse rotation; The engine is connected to the auxiliary motor through the mechanical coupling device to supply electric energy to the electric motor drive unit; The power output ends of the multiple electric motors of the electric motor drive unit are connected to the mechanical coupling device, and the mechanical coupling device couples and outputs the power of the multiple electric motors, the auxiliary motor, and the engine to drive the wheels; The mechanical coupling device adopts a planetary gear mechanism, including a large gear ring, a first sun gear, a first planetary gear, a second sun gear, a second planetary gear, and a planetary carrier; The second sun gear, the second planetary gear, and the planetary carrier are connected in sequence; The first sun gear, the first planetary gear, and the planetary carrier are connected in sequence; The first sun gear and the large gear ring are respectively connected to the power output end of the engine through a clutch structure; the second sun gear is connected to the power output end of the electric motor drive unit; A clutch structure is arranged at the power output end of the engine, and the clutch structure includes a clutch C1, a clutch C2, and a clutch C3; The clutch C1 and the clutch C2 are connected in sequence on the power output shaft of the engine; The clutch C3 is connected to the power output end of the engine through a third gear; The clutch C3 and the clutch C1 are connected to the first sun gear through a fourth gear; a lock LOCK2 is arranged at the power output end of the fourth gear; The clutch C2 is connected to the large gear ring of the planetary gear mechanism through a fifth gear; A lock LOCK1 is arranged outside the large gear ring of the planetary gear mechanism; The lock LOCK2 and the lock LOCK1 are interlocked and controlled to realize the output of different power ranges of the engine, including: When the lock LOCK2 is locked, the lock LOCK1 is disconnected; When the lock LOCK2 is disconnected, the lock LOCK1 is locked; Both the lock LOCK1 and the lock LOCK2 are disconnected.

2. The hybrid electric continuously variable power drive system according to claim 1, wherein: In the electric motor drive unit, the power output end of at least one electric motor is connected to a power take-off shaft PTO.

3. A hybrid electric continuously variable power drive system as claimed in claim 1, wherein: The auxiliary motor rotates forward for power generation, which is used to convert the kinetic energy output by the engine into electric energy; when the auxiliary motor rotates in reverse, it acts as an electric motor and transmits the kinetic energy to the mechanical coupling device for auxiliary drive.

4. A hybrid electric continuously variable power drive system according to claim 1, characterized in that: The electric motor drive unit includes multiple parallel drive branches; Each drive branch includes a power battery and an electric motor connected in series; The power battery is connected to the electric energy output end of the auxiliary motor to receive the electric energy of the auxiliary motor; A clutch is arranged at the output end of each electric motor, and the clutches connected to each electric motor are cascaded and then connected to an input end of the mechanical coupling device through a first gear.

5. A drive control method for a hybrid electric continuously variable transmission power drive system according to any one of claims 1-4, characterized in that, Including the following steps: Obtain a vehicle operation instruction. When starting the vehicle, enter the electric mode; When the vehicle is in the working state and receives a PTO power output instruction, output rotary tillage power through the electric motor; If the required wheel power output is less than a set threshold, enter the engine drive and charging mode, and provide the driving force of the wheels through the engine; Otherwise, enter the cooperative working mode, and provide power for the wheels through the coordinated control of the engine and the electric motor; When the vehicle is in the engine working state and in response to the charging request of the battery, switch to the engine running mode to charge the battery.

6. The drive control method according to claim 5, characterized in that: Engine drive and charging mode, the engine operates to provide charging electrical energy and driving force for the wheels, and the vehicle operation provides driving force through the motor of the motor drive unit; Electric mode, the engine stops operating, and power is provided through the motor of the motor drive unit; When entering the cooperative working mode, according to different wheel loads, the engine and the motor are cooperatively controlled to jointly provide power for the wheels. Specifically: Set a first wheel load threshold range and a second wheel load threshold range with sequentially increasing thresholds; Obtain the wheel load. When within the first wheel load threshold range, control the clutch CMotor1 and the clutch CPTO to engage, and both the lock LOCK1 and the lock LOCK2 are disengaged. The first motor provides power to the power output shaft. After the second motor and the engine are power-coupled, wheel power is provided; When the wheel load is within the second wheel load threshold range, the clutch CMotor2, the clutch CMotor1, and the clutch CPTO are all engaged, and both the lock LOCK1 and the lock LOCK2 are disengaged. The first motor provides power to the power output shaft. After the first motor, the second motor, and the engine are power-coupled, they jointly provide power to the wheels.

7. A tractor, characterized in that: Adopt a hybrid electric continuously variable transmission power drive system according to any one of claims 1-4 to provide power for the operation and wheels of the tractor.

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