Multi-mode hybrid aircraft drive system and control method thereof

Abstract

The invention relates to the technical field of hybrid aircrafts, and discloses a multi-mode hybrid aircraft driving system and a control method thereof, and the multi-mode hybrid aircraft driving system comprises a planetary gear structure, a power structure, a power control structure and a control unit. The planetary gear structure comprises a first planetary gear set and a second planetary gear set, and a planet carrier of the first planetary gear set and a planet carrier of the second planetary gear set are coupled with the rotor wing; the power structure is connected with the planetary gear structure; the power control structure is arranged between the power structure and the planetary gear structure; the control unit controls the power structure and the power control structure so that the first planetary gear set and / or the second planetary gear set can drive the rotor wings to rotate at different powers. By means of the structure, the rotors, the motor and the engine can always work in a high-efficiency interval, and sufficient power storage is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of hybrid aircraft, and particularly to a multi-mode hybrid aircraft drive system and its control method. Background Art

[0002] A multi-axis aircraft is a rotorcraft with three or more rotor shafts. Common multi-axis aircraft include different types such as quad-rotor, octa-rotor, hexa-rotor, and octa-rotor. Taking a quad-rotor aircraft as an example, different from the rotors of a general helicopter, the rotor blades of a multi-axis aircraft usually do not change the blade angle, and its blade angle or pitch remains fixed. It changes the lift of the rotor by independently adjusting the rotational speeds of the four rotors. By changing the attitude of the aircraft and the angle of the rotor rotation plane, it can achieve movement in the air and change direction. Multi-axis aircraft can take off and land vertically, and have simple structures and operations.

[0003] The multi-axis aircraft drives the rotor to work through a gas turbine engine and an electric motor. In the classical power split hybrid scheme, the output shaft rotational speed of the gas turbine engine in the high-efficiency working range is relatively fixed. The aircraft propeller corresponds to different economic rotational speeds in different stages, and the electric motor itself has a high-efficiency working rotational speed range. Based on this, the compatibility of the electric motor in the power split hybrid scheme still needs to be improved. When the rotor rotational speed decreases, the rotational speed of the electric motor drops significantly, and its efficiency may be greatly reduced, resulting in insufficient power reserve when the electric motor and the engine work in the high-efficiency range. Summary of the Invention

[0004] In view of this, the present invention provides a multi-mode hybrid aircraft drive system and its control method to solve the problem that the multi-axis aircraft drives the rotor to work through a gas turbine engine and an electric motor. In the classical power split hybrid scheme, the output shaft rotational speed of the gas turbine engine in the high-efficiency working range is relatively fixed. The aircraft propeller corresponds to different economic rotational speeds in different stages, and the electric motor itself has a high-efficiency working rotational speed range. Based on this, the compatibility of the electric motor in the power split hybrid scheme still needs to be improved. When the rotor rotational speed decreases, the rotational speed of the electric motor drops significantly, and its efficiency may be greatly reduced, resulting in insufficient power reserve when the electric motor and the engine work in the high-efficiency range.

[0005] In a first aspect, the present invention provides a multi-mode hybrid aircraft drive system, including:

[0006] A planetary gear structure, the planetary gear structure includes: a first planetary gear set and a second planetary gear set, and the planet carrier of the first planetary gear set is coupled with the planet carrier of the second planetary gear set to the rotor;

[0007] A power structure, the power structure is connected to the planetary gear structure;

[0008] A power control structure, which is arranged between the power structure and the planetary gear structure;

[0009] A control unit, which controls the power structure and the power control structure so that the first planetary gear set and / or the second planetary gear set drive the rotor to rotate at different powers.

[0010] In an alternative embodiment, the first planetary gear set includes a first sun gear, a first planet carrier and a first ring gear; the second planetary gear set includes a second sun gear, a second planet carrier and a second ring gear;

[0011] The power structure includes: an engine, a first motor and a second motor, and the power control structure includes: a first clutch, a second clutch and a third clutch;

[0012] Wherein, the first planet carrier and the second planet carrier are coupled to the input end of the rotor;

[0013] The output shaft of the first motor is connected to the first sun gear; the output shaft of the second motor is connected to the second sun gear;

[0014] The output shaft of the engine is connected to the first ring gear through the first clutch; the second clutch is arranged between the first sun gear and the second ring gear; the third clutch is arranged on the second ring gear.

[0015] In an alternative embodiment, the hybrid aircraft drive system further includes an electric energy control structure, and the electric energy control structure includes:

[0016] A storage battery and an electric energy distribution unit, the storage battery is connected to the electric energy distribution unit, and the electric energy distribution unit is connected to both the first motor and the second motor.

[0017] Advantageous effects: In the traditional power splitting scheme, a gas turbine engine and a motor drive the rotor to work. By using cylindrical gears and clutches installed between the power source and the rotor, while ensuring its compatibility, the switching of various power sources can be realized. During its normal flight, since the engine speed remains unchanged, when the rotor speed decreases, the motor speed drops significantly, and its efficiency may be greatly reduced. And the technical solution of the present invention is an improved power splitting hybrid scheme, which includes an engine, two motors, three clutches, two planetary gear power splitting devices, a power battery, and an electric energy distribution unit. This configuration can ensure the matching of the rotor speed, motor speed and engine speed of the hybrid power system, and can keep the rotor, motor and engine always working in the high-efficiency range and having sufficient power reserve.

[0018] Second aspect, the present invention also provides a control method for a multi-mode hybrid aircraft drive system, including the following steps:

[0019] Select a working mode according to one or more of the environment, battery power, and rotor power requirements; the control unit controls the working states of the first clutch, the second clutch, and the third clutch according to the selected working mode, and distributes the power paths of the engine, the first motor, and the second motor to drive the rotor to rotate.

[0020] In an optional implementation manner, the working mode includes an urban condition mode;

[0021] In the urban condition mode:

[0022] The controller controls the first clutch to close, the second clutch to disengage, and the third clutch to close;

[0023] The controller controls the engine to be disabled, the first motor and the second motor to operate in motor mode, and the output powers of the first motor and the second motor are converged to the rotor through the first planet carrier and the second planet carrier.

[0024] In an optional implementation manner, the working mode includes a suburban high-power mode:

[0025] In the suburban high-power mode:

[0026] The controller controls the first clutch to disengage, the second clutch to close, and the third clutch to disengage;

[0027] The controller controls the engine to start, and the first motor and the second motor to operate in motor mode;

[0028] The power of the engine is input through the first external gear ring and converges with a part of the power of the first motor to the first planet carrier;

[0029] Another part of the power of the second motor is input to the second planet carrier through the second external gear ring;

[0030] Among them, the first planet carrier and the second planet carrier jointly drive the rotor.

[0031] In an optional implementation manner, the working mode includes a charging cruise mode;

[0032] In the charging cruise mode:

[0033] The controller controls the first clutch to disengage, the second clutch to close, and the third clutch to close;

[0034] The controller controls the engine to start, and the second motor to operate in generator mode;

[0035] A part of the power of the engine is input to the rotor through the first planet carrier, and another part of the power is input to the second motor through the first planet carrier and the second sun gear to drive the second motor to generate electricity.

[0036] In an alternative embodiment, the operating mode includes a high-power cruise mode;

[0037] In the high-power cruise mode:

[0038] The controller controls the first clutch to disengage, the second clutch to disengage, and the third clutch to engage;

[0039] The controller controls to start the engine, the first motor, and the second motor, and the first motor and the second motor operate in the motor mode;

[0040] The power of the engine is input through the first external gear ring, and converges with the power of the first motor through the first sun gear to the first planet carrier;

[0041] The power of the second motor is input to the second planet carrier through the second sun gear;

[0042] Wherein, the first planet carrier and the second planet carrier jointly drive the rotor.

[0043] In an alternative embodiment, the operating mode includes an engine failure mode;

[0044] In the engine failure mode:

[0045] The controller controls the first clutch to engage, the second clutch to disengage, and the third clutch to engage;

[0046] The controller controls to drive the first motor and the second motor to operate in the motor mode, and the output powers of the first motor and the second motor converge to the rotor through the first planet carrier and the second planet carrier.

[0047] In an alternative embodiment, the operating mode includes a motor failure mode;

[0048] In the motor failure mode:

[0049] The controller controls the first clutch to disengage, and the second clutch and the third clutch are simultaneously engaged or disengaged to isolate the faulty motor;

[0050] The rotor is driven by the remaining power source.

[0051] Beneficial effects: By means of regulatory compatibility and on-demand switching between pure electric / hybrid modes, it can meet the full-scenario compliance requirements from urban emission-free zones to suburbs; through planetary gear power splitting and multi-power source coordination, the overall efficiency of the system is improved; and when a certain power source fails, the mode can be switched so that other power sources can promptly supplement the power to drive the rotor, featuring high reliability. By using the battery shallow charge and discharge strategy and the efficient operation range of the engine, the life cycle cost is reduced.

[0052] Compared with the traditional power splitting scheme, the compatibility of this technical solution with motors is higher. For example, the tooth ratio of the outer ring gear to the central sun gear of the planetary gear is 2. There are currently two motors with maximum powers of 100 kW and 500 kW, and the maximum power of the engine is 600 kW. In this technical solution, the maximum output power can reach 1200 kW. In this example, at this time, the rotational speeds of the sun gear, the outer ring gear, and the planet carrier are the same, and the power ratio of the sun gear, the outer ring gear, and the planet carrier can reach 1:2:3. Compared with the traditional power splitting scheme that can output a maximum of 1050 kW, the power that the planet carrier can reach in this embodiment is higher, providing sufficient power reserve for the entire aircraft. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0054] Figure 1 It is a schematic structural diagram of a multi-mode hybrid aircraft drive system according to an embodiment of the present invention;

[0055] Figure 2 It is a schematic structural diagram of a multi-mode hybrid aircraft drive system in the urban working condition mode according to an embodiment of the present invention;

[0056] Figure 3 It is a schematic structural diagram of a multi-mode hybrid aircraft drive system in the suburban high-power mode according to an embodiment of the present invention;

[0057] Figure 4 It is a schematic structural diagram of a multi-mode hybrid aircraft drive system in the charging cruise mode according to an embodiment of the present invention;

[0058] Figure 5 It is a schematic structural diagram of a multi-mode hybrid aircraft drive system in the high-power cruise mode according to an embodiment of the present invention;

[0059] Figure 6Schematic diagram of a multi-mode hybrid aircraft drive system according to an embodiment of the present invention when in an engine failure mode;

[0060] Figure 7 Schematic diagram of a multi-mode hybrid aircraft drive system according to an embodiment of the present invention when in a motor failure mode of a first motor failure;

[0061] Figure 8 Schematic diagram of a multi-mode hybrid aircraft drive system according to an embodiment of the present invention when in a motor failure mode of a second motor failure;

[0062] Explanation of reference numerals:

[0063] 1. First planetary gear set;

[0064] 2. Second planetary gear set;

[0065] 3. Rotor;

[0066] 41. First clutch; 42. Second clutch; 43. Third clutch;

[0067] 5. Battery;

[0068] 6. Electric energy distribution unit;

[0069] 7. Engine;

[0070] 81. First motor; 82. Second motor. Detailed implementation manners

[0071] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts fall within the scope of protection of the present invention.

[0072] A multi-axis aircraft is a rotorcraft with three or more rotors 3. Common multi-axis aircraft include different types such as quad-rotor 3, quad-copter 8-rotor 3, hex-rotor 6-rotor 3, octo-rotor 8-rotor 3, etc. Taking a quad-rotor 4-rotor 3 aircraft as an example, different from the rotors 3 of a general helicopter, a multi-axis aircraft usually does not change the blade angle (pitch) of the rotors 3, and its blade angle or pitch remains fixed. It changes the lift of the rotors 3 by independently adjusting the rotational speeds of the four rotors 3. By changing the attitude of the aircraft and the angle of the rotor 3 rotation plane, air movement and direction change can be achieved. A multi-axis aircraft can take off and land vertically, and has a simple structure and operation.

[0073] The multi-axis aircraft drives the rotor 3 through the gas turbine engine 7 and the motor. However, the output shaft speed of the gas turbine engine 7 in the high-efficiency working range is relatively fixed. The aircraft propeller corresponds to different economic speeds in different stages, and the motor itself has a high-efficiency working speed range. In the classic power split hybrid scheme, it is difficult to ensure that the engine 7, the propeller, and the motor all work in the high-efficiency range within the full envelope. Sometimes, in order to ensure power, the economy will be sacrificed, and sometimes, in order to ensure efficiency, the system power will be sacrificed.

[0074] The following will describe the embodiments of the present invention in conjunction with Figures 1 to 8 .

[0075] According to an embodiment of the present invention, as Figure 1 shown, on the one hand, a multi-mode hybrid aircraft drive system is provided. The hybrid aircraft drive system includes: a planetary gear structure, a power structure, a power control structure, and a control unit (not shown in the figure). The planetary gear structure includes: a first planetary gear set 1 and a second planetary gear set 2. The planet carrier of the first planetary gear set 1 and the planet carrier of the second planetary gear set 2 are coupled to the rotor 3. The first planetary gear set 1 includes a first sun gear, a first planet carrier, and a first outer gear ring. The first planet carrier is coupled to the output shaft of the rotor 3. Three planetary gears are installed between the first sun gear and the first outer gear ring. The second planetary gear set 2 includes a second sun gear, a second planet carrier, and a second outer gear ring. The second planet carrier is coupled to the output shaft of the rotor 3. The output shaft of the rotor 3 is the input end.

[0076] The power structure includes: an engine 7, a first motor 81, and a second motor 82. The output shaft of the engine 7 is connected to the first outer gear ring through a first clutch 41. The first motor 81 is connected to the first sun gear, and the second motor 82 is connected to the second sun gear.

[0077] The power control structure is arranged between the power structure and the planetary gear structure; the power control structure includes: a first clutch 41, a second clutch 42, and a third clutch 43; the first clutch 41 is installed between the output shaft of the engine 7 and the first outer gear ring. The second clutch 42 is arranged between the first sun gear and the second outer gear ring; the third clutch 43 is arranged on the second outer gear ring.

[0078] When the first clutch 41 is closed, the first outer gear ring can be locked, and at this time, the first outer gear ring cannot rotate; when the first clutch 41 is disengaged, the first outer gear ring is unlocked, and the engine 7 can drive the first outer gear ring to rotate. When the second clutch 42 is closed, the first sun gear and the second outer gear ring are connected; when the second clutch 42 is disengaged, the first sun gear and the second outer gear ring are disconnected. When the third clutch 43 is closed, the second outer gear ring can be locked, and at this time, the second outer gear ring cannot rotate; when the third clutch 43 is disengaged, the second outer gear ring is unlocked, and the second outer gear ring can rotate.

[0079] The control unit is used to control the power structure and the power control structure so that the first planetary gear set 1 and / or the second planetary gear set 2 drive the rotor 3 to rotate at different powers.

[0080] The hybrid aircraft drive system further includes an electric energy control structure, and the electric energy control structure includes:

[0081] A storage battery 5 and an electric energy distribution unit 6. The storage battery 5 is connected to the electric energy distribution unit 6, and the electric energy distribution unit 6 is connected to both the first motor 81 and the second motor 82.

[0082] In the traditional power splitting scheme, the gas turbine engine 7 and the motor drive the rotor 3 to work. By using cylindrical gears and clutches installed between the power source and the rotor 3, while ensuring its compatibility, the switching of various power sources can be achieved. During its normal flight, since the engine 7 rotates at a constant speed, when the rotor 3 rotates at a lower speed, the motor speed drops significantly, and its efficiency may be greatly reduced. And this technical solution is an improved power splitting hybrid scheme, including an engine 7, two motors, three clutches, two planetary gear power splitting devices, a power battery, and an electric energy distribution unit 6. This configuration can ensure the matching of the rotor 3 speed, the motor speed and the engine 7 speed of the hybrid power system, and can keep the rotor 3, the motor and the engine 7 always working in the high-efficiency range and having sufficient power reserve.

[0083] According to an embodiment of the present invention, as Figures 2 to 8 described, on the other hand, a control method for a multi-mode hybrid aircraft drive system is also provided, which is adapted to the above multi-mode hybrid aircraft drive system, and includes the following steps: selecting a working mode according to one or more of the environment, the battery 5 power and the rotor 3 power requirement; the control unit controls the working states of the first clutch 41, the second clutch 42 and the third clutch 43 and distributes the power paths of the engine 7, the first motor 81 and the second motor 82 according to the selected working mode to drive the rotor 3 to rotate. Figures 2 to 8 The black solid line in it is mechanical transmission, and the black dotted line is electric energy transmission.

[0084] The working modes include: urban condition mode, high-power mode in the suburbs, charging cruise mode, high-power cruise mode, engine 7 failure mode and motor failure mode.

[0085] Specifically as follows:

[0086] The first working mode: urban condition mode. As Figure 2 shown.

[0087] In urban conditions, due to the requirements of noise and emissions in environmental protection regulations, the engine 7 does not work.

[0088] The controller controls the first clutch 41 to close, the second clutch 42 to disengage, and the third clutch 43 to close. At this time, the first clutch 41 locks the first outer gear ring, the third clutch 43 locks the second outer gear ring, and the first sun gear and the second outer gear ring are in a disengaged state.

[0089] The controller controls the engine 7 to be disabled, and the battery 5 supplies electric power to the first motor 81 and the second motor 82 through the power distribution unit 6. The first motor 81 and the second motor 82 operate in the motor mode. The first motor 81 and the second motor 82 drive the first sun gear and the second sun gear to rotate respectively, while the first outer gear ring and the second outer gear ring are locked at this time.

[0090] The mechanical output powers of the first motor 81 and the second motor 82 are respectively transmitted to the first planet carrier and the second planet carrier through the first sun gear and the second sun gear, and finally converge to the rotor 3. For example: the gear ratios of the two outer gear rings and the corresponding central sun gears are 2:1. At this time, the rotor 3 operates in a higher speed range of 2000 rpm. At this time, the rotational speed of the second motor 82 is 6000 rpm, and the rotational speed of the first motor 81 is 6000 rpm. The output power of the first motor 81 is 500 kW, the output power of the second motor 82 is 100 kW, and the power of the rotor 3 is 600 kW.

[0091] The second working mode: suburban high-power mode; suitable for takeoff / landing in suburban working conditions, or occasions where maximum power, the highest rotational speed of the rotor 3, and maximum thrust lift are required during cruising. As Figure 3 shown.

[0092] Since maximum power is required and the requirements for noise and emissions in environmental protection regulations are reduced, the engine 7 can operate.

[0093] The controller controls the first clutch 41 to disengage, the second clutch 42 to close, and the third clutch 43 to disengage; the first outer gear ring is unlocked and rotatable, the first sun gear and the second outer gear ring are connected through the second clutch 42, and the second outer gear ring is unlocked and rotatable.

[0094] The controller controls the starting of the engine 7. The power battery distributes the electric power to the first motor 81 and the second motor 82 through the power distribution unit 6 so that the two operate in the motor mode. The mechanical power of the engine 7 is transmitted to the first external gear ring, driving the first external gear ring to rotate. The first motor 81 transmits a part of the output mechanical power to the first sun gear, driving the first sun gear to rotate. The power of the first external gear ring and the mechanical power of the first sun gear converge at the first planet carrier and then are provided to the rotor 3, that is, the first external gear ring and the first sun gear together drive the first planet carrier to rotate, and the first planet carrier can drive the rotor 3 to rotate. Another part of the output mechanical power of the first motor 81 is transmitted to the second external gear ring through the second centrifugal clutch and input to the second planet carrier, and the second planet carrier can drive the rotor 3 to rotate. The powers of the first planet carrier and the second planet carrier converge and jointly drive the rotor 3. For example: the tooth ratio of the two planetary gear external gear rings and the corresponding central sun gears is 2:1. The rotational speed of the output shaft of the engine 7 is 3000 rpm. At this time, the rotor 3 operates in the highest rotational speed range of 3000 rpm. The rotational speed of the first motor 81 is 3000 rpm. The rotational speed of the second motor 82 is 3000 rpm. The output rotational speed of the engine 7 is 3000 rpm. The output power of the first motor 81 is 500 kW, the output power of the second motor 82 is 100 kW, the output power of the engine 7 is 600 kW, and the power of the rotor 3 is 1200 kW.

[0095] The third working mode: charging cruise mode. It is suitable for occasions where medium power, medium rotational speed and medium thrust and lift of the rotor 3 are required during cruising. This working mode has the longest working time. As Figure 4 shown.

[0096] The controller controls the disengagement of the first clutch 41, the engagement of the second clutch 42 and the engagement of the third clutch 43; the first external gear ring is unlocked and can rotate. The first sun gear and the second external gear ring are connected through the second clutch 42, and the second external gear ring is locked, and then the first sun gear is indirectly locked through the second clutch 42.

[0097] Due to the relatively low requirements for noise and emissions in environmental protection regulations, the engine 7 can operate. At this time, the remaining state of charge (SOC) of the battery 5 is relatively low and needs to be charged. The controller controls the start of the engine 7, and the second motor 82 operates in generator mode. A part of the power of the engine 7 is input into the rotor 3 through the first external gear ring and the first planet carrier, driving the rotor 3 to rotate. Another part of the mechanical power drives the second sun gear to rotate through the connection between the first planet carrier and the second planet carrier. It can be understood that: the first planet carrier drives the rotor 3 to rotate, and the rotor 3 drives the second planet carrier to rotate. Since the second external gear ring is fixed, the second planet carrier drives the second sun gear to rotate, so that another part of the power of the engine 7 is input into the second motor 82 through the first planet carrier and the second sun gear to drive the second motor 82 to generate electricity. The first motor 81 does not work at this time. For example: the tooth ratio of the external gear rings and the central sun gear of the two planetary gears is 2:1. At this time, the rotor 3 operates in a low-speed range of 2000 rpm. The rotational speed of the second motor 82 is 6000 rpm. The output rotational speed of the engine 7 is 3000 rpm. The output power of the second motor 82 is 100 kW, the output power of the engine 7 is 600 kW, and the power of the rotor 3 is 500 kW.

[0098] The fourth working mode: high-power cruise mode. It is suitable for occasions where a relatively large power, a relatively large rotational speed and a relatively large thrust and lift of the rotor 3 are required during cruising. Such as Figure 5 shown.

[0099] The controller controls the disengagement of the first clutch 41, the disengagement of the second clutch 42 and the engagement of the third clutch 43. The first external gear ring is unlocked and can rotate. The first sun gear is disconnected from the second external gear ring, and the second external gear ring is locked.

[0100] The controller controls the start of the engine 7, the first motor 81 and the second motor 82. The first motor 81 and the second motor 82 operate in motor mode.

[0101] The mechanical power of the engine 7 is transmitted to the first external gear ring, and the mechanical power of the first motor 81 is transmitted to the first sun gear. The mechanical power of the first external gear ring and the first sun gear converges to the first planet carrier.

[0102] The mechanical power of the second motor 82 is transmitted to the second planet carrier through the second sun gear.

[0103] The output power of the second planet carrier and the output power of the second planet carrier converge and are jointly provided to the rotor 3.

[0104] For example: The tooth ratio of the outer rings of two planetary gears and the central sun gear is 2:1. At this time, the rotor 3 operates in the high-speed range, 2500 rpm. The rotational speed of the second motor 82 is 7500 rpm. The output rotational speed of the engine 7 is 3000 rpm. The rotational speed of the first motor 81 is 1500 rpm. The output power of the first motor 81 is 150 kW, the output power of the second motor 82 is 100 kW, the output power of the engine 7 is 600 kW, and the power of the rotor 3 is 850 kW.

[0105] The fifth working mode is the engine 7 failure mode. In this mode, the engine 7 does not work. As Figure 6 shown.

[0106] The controller controls the first clutch 41 to close, the second clutch 42 to disengage, and the third clutch 43 to close; the first outer ring is locked, the first sun gear is disconnected from the second outer ring, and the second outer ring is locked.

[0107] The electric power of the storage battery 5 is supplied to the first motor 81 and the second motor 82 through the electric energy distribution unit 6. The first motor 81 and the second motor 82 operate as motors. The output powers of the first motor 81 and the second motor 82 are respectively input to the first sun gear and the second sun gear, and the powers of the first sun gear and the second sun gear are respectively transmitted to the first planet carrier and the second planet carrier, and finally converge to the rotor 3. For example: The tooth ratio of the outer rings of two planetary gears and the central gear is 2:1. At this time, the rotor 3 operates in a relatively high-speed range, such as 2000 rpm. The rotational speed of the second motor 82 is 6000 rpm, and the rotational speed of the first motor 81 is 6000 rpm. The output power of the first motor 81 is 500 kW, the output power of the second motor 82 is 100 kW, and the power of the rotor 3 is 600 kW.

[0108] The sixth working mode is the failure of the first motor 81 in the motor failure mode. As Figure 7 shown.

[0109] The controller controls the first clutch 41 to disengage, the second clutch 42 to close, and the third clutch 43 to close to isolate the first motor 81. The first outer ring is unlocked, the first sun gear is connected to the second outer ring through the second clutch 42, and the second outer ring is locked, and then the first sun gear is indirectly locked through the second clutch 42.

[0110] The mechanical power of the engine 7 is transmitted to the first outer ring, and all the power of the first outer ring is transmitted to the first planet carrier.

[0111] The electric power of the storage battery 5 is supplied to the second motor 82 through the electric energy distribution unit 6. The second motor 82 operates as a motor and transmits the mechanical power to the second planet carrier through the second sun gear.

[0112] The output power of the second planet carrier converges with the output power of the first planet carrier and is jointly provided to the rotor 3.

[0113] For example: The tooth ratio of the outer tooth rings of two planetary gears and the central sun gear is 2:1. At this time, the rotor 3 operates in the high-speed range of 2000 rpm. The rotational speed of the second motor 82 is 6000 rpm. The output rotational speed of the engine 7 is 6000 rpm. The output power of the second motor 82 is 100 kW, the output power of the engine 7 is 600 kW, and the power of the rotor 3 is 700 kW.

[0114] The seventh working mode, a fault occurs in the second motor 82 in the motor fault mode. As Figure 8 shown.

[0115] The controller controls the first clutch 41 to disengage, the second clutch 42 to disengage, and the third clutch 43 to disengage to isolate the second motor 82. The first outer tooth ring is unlocked.

[0116] The mechanical power of the engine 7 is transmitted to the first outer tooth ring, and all the power of the first outer tooth ring is transmitted to the first planet carrier.

[0117] The electric power of the storage battery 5 is provided to the first motor 81 through the power distribution unit 6. The first motor 81 operates as a motor and transmits the mechanical power to the first planet carrier through the first sun gear.

[0118] The power of the first outer tooth ring and the power of the first sun gear are converged and all given to the first planet carrier, and the first planet carrier drives the rotor 3 to do work.

[0119] For example: The tooth ratio of the outer tooth rings of two planetary gears and the central gear is 2:1. At this time, the rotor 3 operates in the high-speed range of 2500 rpm. The rotational speed of the first motor 81 is 1500 rpm. The output rotational speed of the engine 7 is 3000 rpm. The output power of the first motor 81 is 150 kW, the output power of the engine 7 is 600 kW, and the power of the rotor 3 is 750 kW.

[0120] In the above-mentioned multiple modes, through regulatory compatibility and on-demand switching between pure electric / hybrid modes, it covers the compliance requirements of the entire scenario from urban emission-free zones to suburbs; through planetary gear power splitting and multi-power source coordination, the overall efficiency of the system is improved; and when a certain power source fails, the mode can be switched so that other power sources can timely supplement the power to drive the rotor 3 to work, with high reliability. By using the battery shallow charge and discharge strategy and the efficient operation interval of the engine 7, the life cycle cost is reduced.

[0121] Compared with the traditional power split scheme, this technical solution has a higher compatibility with motors. For example, the tooth ratio of the outer ring gear to the central sun gear of the planetary gear is 2. There are currently two types of motors with maximum powers of 100 kW and 500 kW, and the maximum power of the engine 7 is 600 kW. In this technical solution, the maximum output power can reach 1200 kW. In this example, the rotational speeds of the sun gear, the outer ring gear, and the planetary carrier are the same at this time, and the ratio of the power of the sun gear, the power of the outer ring gear, and the power of the planetary carrier can reach 1:2:3. Compared with the traditional power split scheme that can output a maximum of 1050 kW, the power that the planetary carrier can reach in this embodiment is higher, enabling the entire aircraft to have sufficient power reserve.

[0122] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A multi-mode hybrid aircraft drive system, characterized in that, Comprising: A planetary gear structure, the planetary gear structure comprising: a first planetary gear set (1) and a second planetary gear set (2), the planet carrier of the first planetary gear set (1) and the planet carrier of the second planetary gear set (2) being coupled to the rotor (3); A power structure, the power structure being connected to the planetary gear structure; A power control structure, the power control structure being disposed between the power structure and the planetary gear structure; A control unit, the control unit controlling the power structure and the power control structure such that the first planetary gear set (1) and / or the second planetary gear set (2) drives the rotor (3) to rotate at different powers.

2. The multi-mode hybrid aircraft drive system according to claim 1, wherein The first planetary gear set (1) comprises a first sun gear, a first planet carrier and a first outer gear ring; the second planetary gear set (2) comprises a second sun gear, a second planet carrier and a second outer gear ring; The power structure comprises: an engine (7), a first motor (81) and a second motor (82), and the power control structure comprises: a first clutch (41), a second clutch (42) and a third clutch (43); Wherein, the first planet carrier and the second planet carrier are coupled to the input end of the rotor (3); The output shaft of the first motor (81) is connected to the first sun gear; the output shaft of the second motor (82) is connected to the second sun gear; The output shaft of the engine (7) is connected to the first outer gear ring through the first clutch (41); the second clutch (42) is disposed between the first sun gear and the second outer gear ring; the third clutch (43) is disposed on the second outer gear ring.

3. The multi-mode hybrid aircraft drive system according to claim 2, wherein, The hybrid aircraft drive system further comprises an electric energy control structure, the electric energy control structure comprising: a storage battery (5) and an electric energy distribution unit (6), the storage battery (5) being connected to the electric energy distribution unit (6), and the electric energy distribution unit (6) being connected to both the first motor (81) and the second motor (82).

4. A control method for a multi-mode hybrid aircraft drive system, applicable to the multi-mode hybrid aircraft drive system described in any one of claims 1-3, characterized in that, Comprising the following steps: selecting a working mode according to one or more of the environment, the power of the storage battery (5) and the power requirement of the rotor (3); the control unit controls the working states of the first clutch (41), the second clutch (42) and the third clutch (43) and distributes the power paths of the engine (7), the first motor (81) and the second motor (82) according to the selected working mode to drive the rotor (3) to rotate.

5. The control method of the multi-mode hybrid aircraft drive system according to claim 4, characterized in that, The working mode includes an urban working condition mode; In the urban working condition mode: The controller controls the first clutch (41) to be closed, the second clutch (42) to be disengaged and the third clutch (43) to be closed; The controller controls the engine (7) to be disabled, the first motor (81) and the second motor (82) to operate in the motor mode, and the output powers of the first motor (81) and the second motor (82) are converged to the rotor (3) through the first planet carrier and the second planet carrier.

6. The control method of the multi-mode hybrid aircraft drive system according to claim 4, characterized in that, The working mode includes a suburban high-power mode: In the suburban high-power mode: The controller controls the disengagement of the first clutch (41), the engagement of the second clutch (42), and the disengagement of the third clutch (43); The controller controls the start of the engine (7), the first motor (81), and the second motor (82) to operate in motor mode; The power of the engine (7) is input through the first external gear ring and converges with a part of the power of the first motor (81) to the first planet carrier; Another part of the power of the second motor (82) is input to the second planet carrier through the second external gear ring; Wherein, the first planet carrier and the second planet carrier jointly drive the rotor (3).

7. The control method of the multi-mode hybrid aircraft drive system according to claim 4, wherein The working mode includes a charging cruise mode; In the charging cruise mode: The controller controls the disengagement of the first clutch (41), the engagement of the second clutch (42), and the engagement of the third clutch (43); The controller controls the start of the engine (7), and the second motor (82) operates in generator mode; A part of the power of the engine (7) is input to the rotor (3) through the first planet carrier, and another part of the power is input to the second motor (82) through the first planet carrier and the second sun gear to drive the second motor (82) to generate electricity.

8. The control method of the multi-mode hybrid aircraft drive system according to claim 4, characterized in that, The working mode includes a high-power cruise mode; In the high-power cruise mode: The controller controls the disengagement of the first clutch (41), the disengagement of the second clutch (42), and the engagement of the third clutch (43); The controller controls the start of the engine (7), the first motor (81), and the second motor (82), and the first motor (81) and the second motor (82) operate in motor mode; The power of the engine (7) is input through the first external gear ring and converges with the power of the first motor (81) through the first sun gear to the first planet carrier; The power of the second motor (82) is input to the second planet carrier through the second sun gear; Wherein, the first planet carrier and the second planet carrier jointly drive the rotor (3).

9. The control method of the multi-mode hybrid aircraft drive system according to claim 4, characterized in that, The working mode includes an engine (7) failure mode; In the engine (7) failure mode: The controller controls the engagement of the first clutch (41), the disengagement of the second clutch (42), and the engagement of the third clutch (43); The controller controls to drive the first motor (81) and the second motor (82) to operate in motor mode, and the output power of the first motor (81) and the second motor (82) converges to the rotor (3) through the first planet carrier and the second planet carrier.

10. The control method of the multi-mode hybrid aircraft drive system according to claim 4, characterized in that, The working mode includes a motor failure mode; In the motor failure mode: The controller controls the disengagement of the first clutch (41), and the second clutch (42) and the third clutch (43) are simultaneously engaged or disengaged to isolate the faulty motor; The rotor (3) is driven by the remaining power source.

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