Hybrid powertrain configurations and methods for amphibious mobile platforms

Abstract

This invention relates to a hybrid power transmission system configuration and method for amphibious mobile platforms. An engine and a first motor are coaxially and directly connected to form a first power branch, while a second motor forms a second power branch. The first and second power branches are connected in parallel to different input terminals of the main reducer and transmission system. In flight mode, the flight clutch engages and the ground clutch disengages, with the first and second power branches operating in parallel within the main reducer to drive the flight system. In ground driving mode, the flight clutch disengages and the ground clutch engages, with the engine driving the first motor to generate electricity, which is then transmitted to the second motor to drive the ground wheeled driving system. This invention utilizes a series-parallel hybrid power architecture to simultaneously serve both a tandem dual-rotor flight system and a ground wheeled driving system, achieving integrated transmission with flight / ground mode switching and on-demand power distribution.

Description

Technical Field

[0001] This invention relates to the field of power transmission technology for amphibious transport platforms, and in particular to a hybrid power transmission system configuration and method for amphibious mobile platforms. Background Technology

[0002] Amphibious transport platforms combine vertical takeoff and landing (VTOL) capabilities with wheeled ground mobility, offering unique advantages in military reconnaissance, rapid deployment, and rescue operations in complex terrain. Currently, the power systems of amphibious platforms face the following key technical challenges: First, traditional solutions often employ separate power units for the flight and ground drive systems, resulting in redundant structures, high weight, and a low payload ratio. Second, the power required for hovering is significantly higher than that for ground driving, making it difficult for a single power source to maintain efficient operation under both extreme conditions simultaneously. Third, the transmission system must simultaneously match two loads with different speed characteristics: the flight load (rotor) requires high-speed continuous power output, while the ground load (wheels) requires high torque for low-speed climbing and variable-speed cruise; these characteristics are completely orthogonal. Fourth, existing hybrid power systems are designed for a single load type and lack the ability to simultaneously distribute power to both the flight and ground systems. Summary of the Invention

[0003] In view of this, the present invention provides a hybrid power transmission system configuration and method for amphibious mobile platforms, which uses a series-parallel hybrid power architecture to simultaneously serve a tandem dual-rotor flight system and a ground wheeled driving system, and realizes integrated transmission with flight / ground operating condition switching and power distribution on demand.

[0004] The present invention is achieved through the following technical solution: a hybrid power transmission system configuration for an amphibious mobile platform, including an engine, a first motor, a second motor, a main reducer and transmission system, a flight clutch, a ground clutch, a flight system, a ground wheeled driving system, a power battery and an energy management system; The engine and the first motor are coaxially connected to form a first power branch, and the second motor forms a second power branch. The first power branch and the second power branch are connected in parallel to different input terminals of the main reducer and the transmission system. The main reducer and transmission system are provided with a flight output port and a ground output port; the flight output port is connected to the flight system via a flight clutch, and the ground output port is connected to the ground wheeled driving system via a ground clutch; the energy management system is electrically connected to the power battery, the first motor, and the second motor, and is used to coordinate and control the working modes of the first motor and the second motor and to distribute system energy in real time. In flight mode, the flight clutch engages and the ground clutch disengages, and the first power branch and the second power branch drive the flight system in parallel within the main reducer. In ground driving mode, the flight clutch disengages and the ground clutch engages, the engine drives the first motor to generate electricity, and the electrical energy is transmitted to the second motor to drive the ground wheeled driving system.

[0005] Furthermore, the main reducer and transmission system adopt a three-stage gear reduction mechanism. The first stage is an arc bevel gear pair, with the input end of the first power branch connected to the input shaft of the first-stage arc bevel gear pair, and the input end of the second power branch meshing with the driving gear of the first-stage arc bevel gear pair via the input gear. The second stage is a helical cylindrical gear pair, with the ground output port taken from the output end of the second-stage helical cylindrical gear pair. The third stage is a planetary gear reducer, with the flight output port taken from the final stage output end of the third-stage planetary gear reducer.

[0006] Furthermore, both the first motor and the second motor have the capability to operate in both power generation and electric dual-mode. In flight mode, both the first motor and the second motor can provide electric auxiliary power output and serve as backups for each other. In ground driving mode, the first motor operates as a generator, and the second motor operates as a drive motor to drive the ground driving system.

[0007] Furthermore, the flight system includes a synchronous drive shaft, a front rotor, and a rear rotor; the synchronous drive shaft is used to rigidly and synchronously drive the two rotors; the front rotor and the rear rotor are arranged in a tandem configuration, and the two rotors rotate in opposite directions to balance the counter-torque; the ground wheeled driving system includes a ground reducer, a differential, and a rear drive wheel, with the platform's front wheel being an Ackermann steering wheel, adopting a rear-wheel drive configuration.

[0008] Furthermore, the energy management system divides the power battery's state of charge into four intervals: high charge, normal charge, low charge, and alarm, and adjusts the engine operating point, the first motor's power generation, and the second motor's drive torque in each interval.

[0009] Furthermore, in flight mode, the first power branch directly outputs to the flight system via the main reducer to form a parallel main channel. The second motor operates in an electric manner, and its mechanical power flows from the second input end into the main reducer and superimposes with the first branch at the flight output port to form a parallel boost. In ground driving mode, the engine drives the first motor to generate electricity, which is then supplied to the second motor via the high-voltage electrical bus for electric operation. The electricity is then mechanically fed into the main reducer from the second input end to drive the ground system, forming a series hybrid drive.

[0010] A power control method for a hybrid powertrain configuration as described above is characterized in that the method includes three operating modes: hover / takeoff mode, forward cruise mode, and ground driving mode. Mode switching is achieved by controlling the engagement / disengagement states of the flight clutch and the ground clutch, and the power output of the engine, the first motor, and the second motor is coordinated by the energy management system.

[0011] Furthermore, in hover / takeoff mode and forward cruise mode, the flight clutch engages and the ground clutch disengages; in hover / takeoff mode, the engine operates at maximum takeoff power, and the first and second motors can be selected to drive the total power of the electric auxiliary lifting system; in forward cruise mode, the engine operates at flight cruise power, the first and second motors are in standby mode, and the flight system is directly driven by the engine.

[0012] Furthermore, in ground driving mode, the flight clutch disengages and the ground clutch engages, the engine operates at ground power generation mode, driving the first motor to generate electricity, and the electrical energy is supplied to the second motor via the high-voltage electrical bus to electrically drive the ground driving system; when driving on flat roads, the energy management system lowers the engine operating point to match low power demand; when climbing, the power battery discharges briefly to cooperate with the second motor to output peak torque.

[0013] Compared with existing technologies, the beneficial effects of this invention are: 1. This invention uses a first motor coaxially connected to the engine to form a first branch and a second motor to form a second branch. The dual-branch parallel architecture and the dual output ports of the main reducer enable it to serve both a tandem twin-rotor flight system and a ground wheeled vehicle system with a single transmission configuration, eliminating the structural redundancy problem of traditionally independent dual-system arrangements.

[0014] 2. In the hovering mode of this invention, the engine independently drives the flight system, and both the first and second motors can be selected for hot standby or electric assistance to improve power margin. In forward cruise mode, the engine operates at reduced power to improve fuel economy, and can be briefly boosted to maximum power compensation if necessary.

[0015] 3. The ground driving mechanism of this invention adopts a series path consisting of an engine, a first motor generating electricity, and a second motor driving electricity. The physical decoupling of the generator and the drive motor allows each to operate in its high-efficiency range. When there is a severe overcapacity in power generation under low power demand on flat roads, the energy management system adjusts the engine operating point; when climbing hills, the peak torque can meet the short-term high driving force demand.

[0016] 4. This invention achieves independent switching of the two systems through a flight clutch and a ground clutch. During flight, the ground transmission chain is completely stationary, eliminating drag losses; during ground travel, the flight system does not participate, and all energy is used for propulsion.

[0017] 5. This invention employs spiral bevel gears for steering and primary speed reduction, helical cylindrical gears for precise parallel shaft speed reduction, and planetary gears for high-torque final output. The efficiency of the three-stage cascaded transmission is optimized to achieve a high level. The synchronous drive shaft is made of aerospace alloy steel hollow shaft, and its torsional strength meets the safety factor requirements. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the configuration layout of the hybrid powertrain system of the present invention.

[0019] Figure 2 This is a power flow diagram of the forward cruise operating mode of the present invention.

[0020] Figure 3 This is a power flow diagram of the ground driving working mode of the present invention. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0022] Example 1 This embodiment provides a hybrid power transmission system configuration for amphibious mobile platforms, particularly a series-parallel hybrid power transmission system configuration suitable for tandem twin-rotor land-air amphibious mobile platforms, such as... Figure 1 As shown, the hybrid powertrain configuration includes an engine, a first motor, a second motor, a main reducer and transmission system, a flight clutch, a ground clutch, a flight system, a ground wheeled driving system, a power battery, and an energy management system.

[0023] The flight system includes a synchronous drive shaft, a front rotor, and a rear rotor. The synchronous drive shaft, made of hollow aerospace alloy steel, rigidly drives both rotors synchronously and has a design torque safety factor of not less than 2.0. The front and rear rotors are arranged in a tandem configuration, with the two rotors rotating in opposite directions to balance the anti-torque. In this embodiment, the front and rear rotors are in a tandem twin-rotor configuration, with the two sets of rotors rotating in opposite directions to cancel out the rotor anti-torque, and there is a local overlap between the two rotor disks. The rotors are driven by the synchronous drive shaft to rotate rigidly synchronously at the same speed. In the tandem twin-rotor configuration, there is aerodynamic interference between the front and rear rotors during hovering; the induced power is calculated using an interference factor correction. The tip speed is lower than the airfoil drag divergence Mach number, and the tip Mach number and advance ratio are both within the safe design range during forward movement.

[0024] The ground-based wheeled driving system includes a ground reducer, a differential, and rear drive wheels. The front wheels of the platform are Ackermann steering wheels, and it adopts a rear-wheel drive configuration.

[0025] The engine and the first motor are coaxially connected to form the first power branch, and the second motor forms the second power branch. The first power branch and the second power branch are connected in parallel to the different input terminals of the main reducer and the transmission system.

[0026] The main reducer and transmission system are equipped with flight output ports and ground output ports. The flight output port is connected to the flight system via a flight clutch, and the ground output port is connected to the ground wheeled driving system via a ground clutch. The energy management system is electrically connected to the power battery, the first motor, and the second motor, and is used to coordinate and control the operating modes of the first and second motors and to distribute system energy in real time. The power battery serves as both the energy source and energy storage device for the two motors, with a usable capacity of approximately 15kWh and a peak discharge power of not less than 120kW, supporting short-term peak torque assistance for the second motor.

[0027] like Figure 2 As shown, in flight mode, the flight clutch engages and the ground clutch disengages, and the first power branch and the second power branch drive the flight system in parallel within the main reducer; in ground driving mode, the flight clutch disengages and the ground clutch engages, the engine drives the first motor to generate electricity, and the electrical energy is transmitted to the second motor to drive the ground wheeled driving system.

[0028] Specifically, the flight output port drives both the front and rear rotors simultaneously via a flight clutch and a synchronous drive shaft. The ground output port connects to the ground reducer, differential, and rear drive wheel in sequence via a ground clutch. In flight mode, the flight clutch engages and the ground clutch disengages, allowing engine power to directly drive the front and rear rotors via the main reducer, while the ground driving system remains completely stationary. In ground driving mode, the flight clutch disengages and the ground clutch engages, driving the first motor to generate electricity. This electrical energy is distributed to the second motor via the energy management system, and the second motor's output drives the rear wheel via the ground reducer and differential.

[0029] The series and parallel characteristics of this series-parallel hybrid power transmission configuration are reflected in the differentiated power coupling paths under different operating modes: In flight mode, the first power branch directly outputs mechanical power to the flight system via the main reducer and transmission system, while the second power branch can be controlled by the energy management system to operate electrically. It merges into the main reducer and transmission system from the second input end and superimposes with the first branch at the flight output port to form a parallel boost. That is, the flight mode exhibits the characteristics of dual-branch parallel operation.

[0030] like Figure 3 As shown, in ground driving mode, the engine drives the first motor to generate electricity. The generated electricity is transmitted to the second motor for electric operation via the high-voltage electrical bus (rectifier-DC bus-inverter). Then, it is fed into the main reducer and transmission system from the second input terminal to drive the ground system. This path is a series hybrid drive of "engine-generator-motor", that is, the ground mode exhibits series characteristics.

[0031] The energy management system coordinates and controls the operating modes and power output of the first and second motors, as well as the energy distribution. In ground driving mode, the energy management system controls the electrical energy generated by the first motor to be supplied to the second motor via the high-voltage electrical bus, and adjusts the engine operating point and the torque distribution between the two motors in real time based on the state of charge of the power battery. The energy management system divides the power battery's state of charge into four zones: high charge, normal charge, low charge, and alarm, and adjusts the engine operating point, the power output of the first motor, and the driving torque of the second motor in each zone.

[0032] In this embodiment, the main reducer and transmission system employ a three-stage gear reduction mechanism. The first stage is a spiral bevel gear pair, achieving a 90-degree input steering reversal and primary speed reduction. The second stage is a helical cylindrical gear pair, achieving parallel shaft speed reduction. The third stage is a planetary gear reducer, achieving high-torque final output. The three stages connected in series reduce the high-speed input of the engine and motor to the rated speed required by the rotor. All three gears are manufactured using high-precision machining and high-strength materials, and are lubricated with high-quality synthetic lubricant to ensure transmission efficiency and reliability.

[0033] The first-stage spiral bevel gear pair has a transmission ratio of approximately 1.5, the second-stage helical cylindrical gear pair has a transmission ratio of approximately 2.5, and the third-stage planetary gear reducer has a transmission ratio of approximately 4.0, with a total transmission ratio of approximately 15. This can reduce the high input speed of the engine and motor to the rated speed of the front and rear rotors, which is 600 rpm. The ground output port is led out after the second-stage gear, and then drives the rear wheels after passing through two stages of helical gear reduction in the ground reducer and the limited-slip differential.

[0034] The main reducer and transmission system have two input ends and two output ends, with the following specific connection relationships: The first input end (corresponding to the first power branch) is located on the input shaft of the first-stage spiral bevel gear pair, receiving mechanical power from the direct coaxial connection between the engine and the first motor. The second input end (corresponding to the second power branch) is located at the input end of the first-stage reducer, meshing with the first-stage drive gear via the input gear, and receiving mechanical power from the second motor. The power from the two branches converges in parallel at the first-stage gear, and then is sequentially reduced in speed by a series connection of the second-stage helical cylindrical gear pair and the third-stage planetary gear reducer.

[0035] On the output side: the flight output port is taken from the final stage output of the third-stage planetary gear reducer, providing the low-speed, high-torque output required by the rotor; the ground output port is taken from the output of the second-stage helical cylindrical gear pair (i.e., the intermediate stage before the third stage), and is then led out via the ground clutch and further reduced to wheel speed by the ground reducer. In other words, both branches are connected to the first-stage input, with the flight output taken from the final stage of the third stage and the ground output from the intermediate stage of the second stage. The configuration is clearly hierarchical, and the flight and ground power paths do not interfere with each other.

[0036] The engine is an aviation heavy oil engine with a rated power of approximately 150kW under maximum takeoff power condition, approximately 90kW under flight cruise condition, and approximately 60kW under ground power generation condition. It can operate under four standard conditions: maximum takeoff power condition, flight cruise power condition, ground power generation condition, and idle condition. The power output range covers the full range of operating conditions required for flight hovering, forward cruise, and ground tandem driving.

[0037] The first and second motors are the same model of permanent magnet synchronous motors, with a rated power P_m of approximately 75kW, a peak power of approximately 120kW, a rated speed n_m of approximately 6000r / min, and a maximum efficiency of no less than 95%. Both the first and second motors have dual-mode operation capabilities for both power generation and electric operation, and can independently switch between these modes. In flight mode, both motors can provide electric auxiliary power output and serve as backups for each other. In ground driving mode, the first motor operates as a generator, while the second motor acts as a drive motor to power the ground driving system. The fact that the first and second motors are of the same model reduces the types of spare parts and maintenance complexity, and they also serve as backups for each other in flight mode.

[0038] Example 2 This embodiment provides a power control method for the above-mentioned hybrid power transmission system configuration. The power control method includes three working modes: hover / takeoff mode, forward cruise mode, and ground driving mode. The mode switching is achieved by controlling the engagement / disengagement state of the flight clutch and the ground clutch. The power output of the engine, the first motor, and the second motor is coordinated by the energy management system.

[0039] In hover / takeoff mode and forward cruise mode, the flight clutch engages and the ground clutch disengages. In hover / takeoff mode, the engine operates at maximum takeoff power, and the first and second motors can be selected to drive the total power of the electric auxiliary lifting system. In forward cruise mode, the engine operates at flight cruise power, the first and second motors are in standby mode, and the flight system is directly driven by the engine.

[0040] Specifically, such as Figure 2 As shown, hovering / takeoff mode requires maximum power output. The flight clutch engages, the ground clutch disengages, and the engine operates at maximum takeoff power. Power is input to the main reduction gear via the first power branch, and after three-stage gear reduction, it simultaneously drives the nose and rear rotors through the flight output port and synchronous drive shaft. The engine can independently meet hovering requirements. In this mode, the first motor can be selected for hot standby to increase system margin, and the second motor can also be selected for electric assistance to provide greater power redundancy. The total system power reaches its maximum when both motors are assisting simultaneously. The ground reduction gear, differential, and wheels do not rotate with the engine, eliminating ground drive chain drag losses during flight.

[0041] In forward cruise mode, flight power requirements are reduced, and the engines operate at reduced power to improve fuel economy. The flight clutch engages, the ground clutch disengages, and the engines operate at flight cruise power, with power directly driving the flight system via the main gearbox. The first and second motors are in standby mode and do not participate in power transmission. The flight system is directly driven by the engines, resulting in the highest transmission efficiency. In forward cruise mode, both the propeller tip Mach number and advance ratio are well below safety limits.

[0042] In ground driving mode, the flight clutch disengages and the ground clutch engages, and the flight system is completely stationary in this mode. The engine operates at ground power generation capacity, driving the first motor to generate electricity. The alternating current is converted into high-voltage direct current by a rectifier and fed into the DC bus. After being distributed by the energy management system, the DC power is converted back into alternating current by an inverter to drive the second motor, which in turn drives the ground driving system.

[0043] Under ground-based power generation conditions, the first motor's power output can cover the needs of driving on flat roads and reserve sufficient power margin. When there is excess power generation, the energy management system can reduce the engine's output power or store the excess electrical energy in the power battery. When climbing steep inclines for a short period of time, the second motor can utilize its peak torque capability and the battery's short-term discharge to meet the driving force requirements.

[0044] The switching between the three operating modes is triggered by commands from the flight control system or pilot operation. This switching is achieved by adjusting the engagement and disengagement of the flight clutch and ground clutch, synchronously matching the corresponding engine operating conditions. When switching from ground travel to hover takeoff, the second motor is first disengaged from the ground drive load, the engine is increased to maximum takeoff power, and then the flight clutch is engaged to drive the rotor to accelerate. Full retraction of the landing gear is a prerequisite for the safety interlock in this switching process. The switch from hover to forward flight is achieved through cyclic pitch control combined with engine power reduction. The switch from forward flight to hover is completed through deceleration combined with engine power increase. When hovering to landing, the rotor decelerates, the ground contact sensor confirms the contact, the flight clutch disengages, the ground clutch engages, and the first motor switches to generator mode.

[0045] This power control method also possesses complete fault-tolerant control logic: when the first motor fails, the entire aircraft loses its power generation capacity. In ground operation, it can only rely on the power battery to drive the second motor for short-distance travel, while in flight operation, the engine independently drives the rotor to maintain hovering. When the second motor fails, the platform loses ground drive and flight assistance power, and can only rely on the engine to drive the rotor for flight. After the failure, it needs to land and dock as soon as possible. If the aviation heavy oil engine experiences a shutdown failure, the power battery can work with the two motors to output power to drive the rotor for a short time, and the platform needs to immediately perform an emergency landing operation. When the power battery fails, the system loses its energy buffering capacity, and the energy management system matches the power generated by the first motor in real time to directly supply the second motor. If the flight clutch fails and locks in the disengaged position, the system prohibits takeoff operations and only allows ground travel. If the ground clutch cannot engage normally, the platform can only perform flight missions and conduct maintenance after landing.

[0046] This invention achieves efficient power distribution for multiple operating conditions, including flight hovering / cruising and ground driving, by having the engine and the first motor coaxially form a first power branch, the second motor form an independent second power branch, and the two branches are connected in parallel to the same main reducer and are equipped with flight output ports and ground output ports.

[0047] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A hybrid power transmission system configuration for an amphibious mobile platform, characterized in that, It includes an engine, a first motor, a second motor, a main reducer and transmission system, a flight clutch, a ground clutch, a flight system, a ground wheeled driving system, a power battery, and an energy management system; The engine and the first motor are coaxially connected to form a first power branch, and the second motor forms a second power branch. The first power branch and the second power branch are connected in parallel to different input terminals of the main reducer and the transmission system. The main reducer and transmission system are provided with a flight output port and a ground output port; the flight output port is connected to the flight system via a flight clutch, and the ground output port is connected to the ground wheeled driving system via a ground clutch; the energy management system is electrically connected to the power battery, the first motor, and the second motor, and is used to coordinate and control the working modes of the first motor and the second motor and to distribute system energy in real time. During flight, the flight clutch engages and the ground clutch disengages, and the first power branch and the second power branch drive the flight system in parallel within the main gearbox. In ground driving mode, the flight clutch disengages and the ground clutch engages, the engine drives the first motor to generate electricity, and the electrical energy is transmitted to the second motor to drive the ground wheeled driving system.

2. The hybrid powertrain configuration according to claim 1, characterized in that, The main reducer and transmission system adopt a three-stage gear reduction mechanism. The first stage is an arc bevel gear pair. The input end of the first power branch is connected to the input shaft of the first stage arc bevel gear pair. The input end of the second power branch meshes with the driving gear of the first stage arc bevel gear pair through the input gear. The second stage is a helical cylindrical gear pair, and the ground output port is taken from the output end of the second stage helical cylindrical gear pair; the third stage is a planetary gear reducer, and the flight output port is taken from the final stage output end of the third stage planetary gear reducer.

3. The hybrid powertrain configuration according to claim 1, characterized in that, Both the first motor and the second motor have the ability to operate in both power generation and electric dual-mode. In flight mode, both the first motor and the second motor can output power electrically and serve as backups for each other. In ground driving mode, the first motor operates as a generator, and the second motor operates as a drive motor to drive the ground driving system.

4. The hybrid powertrain configuration according to claim 1, characterized in that, The flight system includes a synchronous drive shaft, a front rotor, and a rear rotor; the synchronous drive shaft is used to rigidly and synchronously drive the two rotors; the front rotor and the rear rotor are arranged in a tandem configuration, and the two rotors rotate in opposite directions to balance the counter-torque. The ground wheeled driving system includes a ground reducer, a differential, and rear drive wheels. The front wheels of the platform are Ackermann steering wheels, and it adopts a rear-wheel drive configuration.

5. The hybrid powertrain configuration according to claim 1, characterized in that, The energy management system divides the power battery into four intervals based on its state of charge: high charge, normal charge, low charge, and alarm. It then adjusts the engine operating point, the power generation of the first motor, and the driving torque of the second motor in each interval.

6. The hybrid powertrain configuration according to any one of claims 1 to 5, characterized in that, In flight mode, the first power branch directly outputs to the flight system via the main reducer to form a parallel main channel. The second motor runs in an electric manner, and its mechanical power flows from the second input end into the main reducer and superimposes with the first branch at the flight output port to form a parallel boost. In ground driving mode, the engine drives the first motor to generate electricity, which is then supplied to the second motor via the high-voltage electrical bus for electric operation. The electricity is then mechanically fed into the main reducer from the second input end to drive the ground system, forming a series hybrid drive.

7. A power control method for a hybrid powertrain configuration as described in any one of claims 1 to 6, characterized in that, The method includes three working modes: hovering / takeoff mode, forward cruise mode, and ground driving mode. The mode switching is achieved by controlling the engagement / disengagement of the flight clutch and the ground clutch, and the power output of the engine, the first motor, and the second motor is coordinated by the energy management system.

8. The power control method according to claim 7, characterized in that, In hover / takeoff mode and forward cruise mode, the flight clutch engages and the ground clutch disengages. In hover / takeoff mode, the engine operates at maximum takeoff power, and the first and second motors can be selected to drive the total power of the electric auxiliary lifting system. In forward cruise mode, the engine operates at flight cruise power, the first and second motors are in standby mode, and the flight system is directly driven by the engine.

9. The power control method according to claim 7, characterized in that, In ground driving mode, the flight clutch disengages and the ground clutch engages, the engine operates at ground power generation mode, driving the first motor to generate electricity. The electrical energy is supplied to the second motor via the high-voltage electrical bus to drive the ground driving system. When driving on flat roads, the energy management system lowers the engine operating point to match low power demand. When climbing, the power battery discharges briefly to cooperate with the second motor to output peak torque.

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