Helicopter ducted tail rotor magnetic suspension electric drive configuration

Abstract

The application discloses a helicopter duct tail rotor magnetic suspension electric driving configuration, which comprises a stator support, a machine shell, a rotor blade, a permanent magnet synchronous motor, a first magnetic suspension system, a second magnetic suspension system and a mechanical protection bearing; the stator support is sequentially provided with a support inner shaft, a supporting strip and a support outer ring from inside to outside; the support inner shaft is coaxial with the support outer ring and forms an integral whole by the uniformly distributed supporting strip; and the uniformly distributed supporting strip can provide a wiring channel while reducing the weight of the stator support. The application adopts the magnetic suspension system to replace the mechanical bearing for support, eliminates the wear of the conventional mechanical bearing of the helicopter duct tail rotor, generates controllable electromagnetic force by the magnetic suspension system, controls the disturbance of the air to the direct drive type electric system of the helicopter duct tail rotor in real time, reduces the vibration generated by the air disturbance, and further improves the stability and safety of the helicopter flight.

Description

Technical Field

[0001] This invention belongs to the field of magnetic levitation electric drive technology, specifically relating to a magnetic levitation electric drive configuration for a helicopter ducted tail rotor. Background Technology

[0002] With the increasing depletion of global fossil energy and the continuous development of new energy technologies, the traditional mechanical transmission configuration of helicopter ducted tail rotors is expected to be replaced by electric drive configurations. In order to improve the helicopter's stealth penetration, rapid maneuverability, and battlefield survivability, high requirements are placed on the suppression of heat generation, noise, and vibration issues in the electric drive configuration of helicopter ducted tail rotors.

[0003] The existing ducted tail rotor electric drive configuration of helicopters mainly adopts the direct drive electric drive configuration. The direct drive electric drive configuration directly connects the rotor of the drive motor to the tail rotor blades, omitting components such as the drive shaft and reducer. It has the characteristics of simple structure, short transmission chain, high system efficiency, and convenient installation and maintenance. It makes up for the shortcomings of traditional mechanical transmission configuration, such as complex structure, long transmission chain, large mechanical noise of reducer, large vibration of drive shaft, and long installation and maintenance cycle, and brings convenience to the overall layout of helicopters.

[0004] In existing helicopter ducted tail rotor direct-drive electric drive configurations, the rotor is mostly supported by mechanical bearings. Wear of mechanical bearings leads to a decrease in system mechanical efficiency. To reduce wear of mechanical bearings, a separate lubrication system is required. While some existing systems that use organic working fluids to lubricate mechanical bearings can reduce wear, they suffer from problems such as complex lubrication channels and easy lubricant leakage. In addition, wear of mechanical bearings can further cause heat generation and noise, reducing the reliability and stealth capability of helicopter flight.

[0005] Existing helicopter ducted tail rotors rotate at high speeds during hovering. Unpredictable aerodynamic disturbances can cause vibrations in the tail rotor blades, which not only exacerbates the wear of mechanical bearings and reduces the service life of the direct-drive electric drive system for helicopter ducted tail rotors, but also transmits the vibrations of the tail rotor blades directly to the helicopter fuselage through the direct-drive electric drive configuration, reducing the stability and safety of helicopter flight. Summary of the Invention

[0006] Purpose of the invention: To address the shortcomings of existing technologies, this invention provides a magnetic levitation electric drive configuration for helicopter ducted tail rotors, thereby solving problems such as heat generation, noise, and vibration associated with existing helicopter ducted tail rotor electric drive configurations.

[0007] Technical Solution: A helicopter ducted tail rotor magnetic levitation electric drive configuration includes a stator support, a housing, rotor blades, a permanent magnet synchronous motor, a first magnetic levitation system, a second magnetic levitation system, and a mechanical protection bearing. The stator support, from the inside out, consists of an inner shaft, support bars, and an outer ring. The inner shaft and the outer ring are coaxial and formed by evenly distributed support bars, which reduce the weight of the stator support while providing wiring channels. The outer ring has stepped surfaces, locating pin holes, and threaded holes on its radially outer and inner sides to position and fix the stator portion of the permanent magnet synchronous motor and the stator portion of the first magnetic levitation system. The outer ring also has locating pin holes and threaded holes on its axially opposite end faces to position and fix the stator portion of the second magnetic levitation system. Through holes are formed on the radially cylindrical surface and axial end face of the inner shaft to lead out the wires of the permanent magnet synchronous motor, the first magnetic levitation system, and the second magnetic levitation system.

[0008] Further, the housing includes a first housing and a second housing. The first housing, from the inside out, consists of a first inner ring, a first end face, a first connecting strip, and a first outer ring. The second housing, from the inside out, consists of a second inner ring, a second end face, a second connecting strip, and a second outer ring. The first inner ring and the first outer ring are coaxial, and the first inner ring and the first end face are integrally formed. The first inner ring and the first outer ring are also integrally formed by the evenly distributed first connecting strips. The evenly distributed first connecting strips not only reduce the weight of the first housing but also provide cooling channels. The airflow generated when the helicopter's ducted tail rotor rotates passes through the gaps in the first connecting strips for cooling. The second... The inner ring is coaxial with the second outer ring, and the second inner ring is integral with the second end face. It is also formed as a whole by the evenly distributed second connecting strips and the second outer ring. The evenly distributed second connecting strips not only reduce the weight of the second housing, but also provide cooling channels. Through holes are opened on the axial end faces of the first outer ring and the second outer ring, and the rotor part of the permanent magnet synchronous motor is fixed by screws. Through holes are opened on the first end face and the second end face, and the rotor part of the second magnetic levitation system is fixed by screws. Evenly distributed grooves are opened on the radial outer sides of the first outer ring and the radial outer sides of the second outer ring to realize the installation of the blades.

[0009] Furthermore, the permanent magnet synchronous motor includes an inner stator core, an outer rotor core, permanent magnets, and motor windings; the inner stator core is coaxial with the outer rotor core, the inner stator core is installed on the outer side of the bracket outer ring, circumferentially positioned by a positioning pin, and axially fixed by a rubber retaining ring; the outer rotor core is installed on the inner side of the first outer ring and the second outer ring, and axially fixed by screws; the permanent magnets are evenly distributed on the inner side of the outer rotor core, and axially limited by the first housing and the second housing; the motor windings are located on the teeth of the inner stator core.

[0010] Furthermore, the radial magnetic levitation system includes four radial stator cores, a radial rotor core, radial displacement sensors, four radial sensor detection rings, and radial windings. The radial stator cores are evenly distributed and installed on the inner side of the outer ring of the bracket, circumferentially positioned by locating pins and axially fixed by screws. Every two radial stator cores spaced 180° apart form a group, and there are two groups of radial stator cores in total. The radial rotor core is installed on the outer side of the first inner ring by an interference fit. The radial displacement sensors are evenly distributed and installed in the through holes opened in the inner shaft of the bracket. Every two radial displacement sensors spaced 180° apart form a group, and there are two groups of radial displacement sensors in total. Each radial displacement sensor corresponds to one radial stator core. The radial sensor detection rings are installed on the inner side of the first inner ring by an interference fit. The radial windings are located on the teeth of the radial stator cores.

[0011] Furthermore, the axial magnetic levitation system includes six axial first stator cores, six axial second stator cores, two axial rotor cores, six axial displacement sensors, and axial windings. The axial first stator cores are evenly distributed and installed on both axial end faces of the outer ring of the bracket, circumferentially positioned by locating pins, and axially fixed by screws. Two axial first stator cores located on the axial end faces of the outer ring of the bracket and on the same axis form a group, resulting in three groups of axial first stator cores. The axial second stator cores are evenly distributed on both axial end faces of the outer ring of the bracket and circumferentially positioned by locating pins. The axial second stator cores are axially fixed by screws. Three axial second stator cores located on each side of the outer ring of the bracket form a group, resulting in two groups of axial second stator cores. Two axial rotor cores are respectively installed on the inner sides of the first and second end faces and axially fixed by screws. The axial displacement sensor is installed in a groove in the axial first stator core. Two axial displacement sensors in each group of axial first stator cores form a group, resulting in three groups of axial displacement sensors. The axial windings are located in grooves in the axial first stator core and the axial second stator core.

[0012] Furthermore, the mechanical protection bearing includes a first mechanical protection bearing and a second mechanical protection bearing. The mechanical protection bearing is an angular contact ball bearing. The first mechanical protection bearing and the second mechanical protection bearing are respectively installed on the outer side of the first end face and the second end face, and are axially fixed by end caps. When the radial displacement of the rotor is too large, the inner ring surface of the mechanical protection bearing contacts the cylindrical surface of the inner shaft of the bracket to achieve radial protection; when the axial displacement of the rotor is too large, the inner ring end face of the mechanical protection bearing contacts the shoulder of the inner shaft 1 of the bracket to achieve axial protection.

[0013] Furthermore, when the helicopter ducted tail rotor magnetic levitation electric drive configuration is in operation, the radial magnetic levitation system counteracts the gravity of the helicopter ducted tail rotor part, which includes the housing, the outer rotor core, the permanent magnet, the radial rotor core, the radial sensor detection ring, the axial rotor core, the first protective bearing, the second protective bearing, and the blades, to achieve radial levitation. The axial magnetic levitation system also counteracts the force exerted by the air on the blades when they rotate, to achieve axial levitation.

[0014] Furthermore, the radial magnetic levitation system contains two sets of radial stator cores controlled using a differential mechanism. In each set of radial displacement sensors, if the displacement signal detected by one radial displacement sensor decreases, the displacement signal of the other increases. Correspondingly, in the set of radial stator cores corresponding to that set of radial displacement sensors, the electromagnetic force generated by the radial stator core on the side with decreasing displacement decreases, while the electromagnetic force on the side with increasing displacement increases, causing the rotor to return to the radial equilibrium point. The two sets of radial stator cores respectively control the helicopter ducted tail rotor section along... x Translation in the axial direction and y Translation in the axial direction.

[0015] Furthermore, the three sets of axial first stator cores in the axial magnetic levitation system are controlled using a differential principle. Specifically, within the same set of axial first stator cores and corresponding axial displacement sensors, if the signal detected by one axial displacement sensor decreases, the displacement signal of the other increases. Correspondingly, within the set of axial first stator cores corresponding to that set of axial displacement sensors, the electromagnetic force generated by the axial first stator core on the side with decreasing displacement decreases, while the electromagnetic force on the side with increasing displacement increases, causing the rotor to return to the axial equilibrium point. The three sets of axial first stator cores work together to control the helicopter ducted tail rotor section along... z Translation in the axial direction x Rotation in the axial direction and y Rotation in the axial direction.

[0016] Furthermore, under low-speed operating conditions, the electromagnetic force generated by the axial first stator core can control the helicopter ducted tail rotor section along... z Translation in the axial direction x Rotation in the axial direction and y The axial rotation, especially under hovering conditions, results in excessive axial aerodynamic loads. The first axial stator core alone cannot generate sufficient load-bearing capacity; therefore, a second axial stator core is required in addition to the first. The two sets of second axial stators in the axial magnetic levitation system are controlled using a differential mechanism. Each set of second axial stators is uniformly controlled by the average value detected by three axial displacement sensors on the same side, generating a rotational force along the axis... z An electromagnetic force in the axial direction, opposite to the direction of the air force acting on the rotor blades, is generated by the second axial stator core. This axial electromagnetic force is superimposed on the axial electromagnetic force generated by the first axial stator core, enhancing the electromagnetic force exerted on the helicopter ducted tail rotor section along the axis. z The ability to control axial translation. Beneficial effects

[0017] (1) By using a magnetic levitation system to replace mechanical bearings for support, the wear of traditional mechanical bearings of helicopter ducted tail rotors is eliminated. This not only eliminates the need for flow channel design of mechanical support lubrication system and solves the problem of lubricant leakage, but also avoids heat generation and noise caused by mechanical support wear, further improving the reliability and stealth of helicopter flight.

[0018] (2) By using a magnetic levitation system to generate controllable electromagnetic force, the disturbances caused by air to the direct-drive electric system of the helicopter ducted tail rotor are controlled in real time, reducing the vibration caused by air disturbances and mitigating the impact of the direct-drive tail rotor configuration on the air disturbances being directly transmitted to the fuselage, thereby further improving the stability and safety of helicopter flight. Attached Figure Description

[0019] Figure 1 This is a general structural diagram of a helicopter ducted tail rotor magnetic levitation electric drive configuration.

[0020] Figure 2 A plan view of a helicopter ducted tail rotor magnetic levitation electric drive configuration.

[0021] Figure 3 A set of radial magnetic levitation bearings for a helicopter ducted tail rotor;

[0022] Figure 4 A set of axial magnetic levitation bearings for a helicopter ducted tail rotor;

[0023] Figure 5An axial stator core for a helicopter ducted tail rotor magnetic levitation electric drive configuration;

[0024] The labels are as follows: 1—Inner shaft of the bracket; 2—Support bar; 3—Outer ring of the bracket; 4—First inner ring; 5—First end face; 6—First connecting bar; 7—First outer ring; 8—Second inner ring; 9—Second end face; 10—Second connecting bar; 11—Second outer ring; 12—Inner stator core; 13—Outer rotor core; 14—Permanent magnet; 15—Motor winding; 16—Radial stator core; 17—Radial rotor core; 18—Radial displacement sensor; 19—Radial sensor detection ring; 20—Radial winding; 21—Axial first stator core; 22—Axial second stator core; 23—Axial rotor core; 24—Axial displacement sensor; 25—Axial winding; 26—First mechanical protection bearing; 27—Second mechanical protection bearing; 28—Blade; 29—Rubber retaining ring. Detailed Implementation

[0025] The present invention will be further described below with reference to the accompanying drawings:

[0026] like Figure 1 , Figure 2 The helicopter ducted tail rotor magnetic levitation electric drive configuration shown mainly includes a stator support, a housing, blades, a permanent magnet synchronous motor, a first magnetic levitation system, a second magnetic levitation system, and a mechanical protection bearing. The stator support consists of an inner shaft 1, support bars 2, and an outer ring 3 from the inside out. The inner shaft 1 and the outer ring 3 are coaxial and are formed by the evenly distributed support bars 2. The evenly distributed support bars 2 reduce the weight of the stator support and provide wiring channels. Compared with the integral connection surface, the evenly distributed support bars not only remove excess material and reduce the weight of the stator support, but also provide wiring channels for the wires led out from the motor and magnetic levitation bearing windings. The wires are led out through the central through hole of the inner shaft of the stator support to realize external power supply to the motor and magnetic levitation bearing. The outer and inner radial sides of the bracket outer ring 3 are provided with stepped surfaces, positioning pin holes, and threaded holes to achieve the positioning and fixation of the stator part of the permanent magnet synchronous motor and the stator part of the first magnetic levitation system; the axial two-sided end faces of the bracket outer ring 3 are provided with positioning pin holes and threaded holes to achieve the positioning and fixation of the stator part of the second magnetic levitation system; the radial cylindrical surface and axial end face of the bracket inner shaft 1 are provided with through holes to lead out the wires of the permanent magnet synchronous motor, the first magnetic levitation system, and the second magnetic levitation system.

[0027] The housing includes a first housing and a second housing. The first housing, from the inside out, consists of a first inner ring 4, a first end face 5, a first connecting strip 6, and a first outer ring 7. The second housing, from the inside out, consists of a second inner ring 8, a second end face 9, a second connecting strip 10, and a second outer ring 11. The first inner ring 4 and the first outer ring 7 are coaxial and integral with the first end face 5. The first inner ring 4 and the first outer ring 7 are formed by the evenly distributed first connecting strips 6. The evenly distributed first connecting strips 6 not only reduce the weight of the first housing but also provide cooling channels. The airflow generated when the helicopter's ducted tail rotor rotates passes through the gaps in the first connecting strips 6 for cooling.

[0028] The second inner ring 8 is coaxial with the second outer ring 11. The second inner ring 8 and the second end face 9 are integral, and the second outer ring 11 is formed by the evenly distributed second connecting strips 10. The evenly distributed second connecting strips 10 can not only reduce the weight of the second housing, but also provide a cooling channel. The axial end face of the first outer ring 7 and the axial end face of the second outer ring 11 are provided with through holes, and the rotor part of the permanent magnet synchronous motor is fixed by screws. The first end face 5 and the second end face 9 are provided with through holes, and the rotor part of the second magnetic levitation system is fixed by screws. The radially outer side of the first outer ring 7 and the radially outer side of the second outer ring 11 are provided with evenly distributed grooves to realize the installation of the blades 28.

[0029] The permanent magnet synchronous motor includes an inner stator core 12, an outer rotor core 13, permanent magnets 14, and motor windings 15. The inner stator core 12 is coaxial with the outer rotor core 13. The inner stator core 12 is installed on the outer side of the bracket outer ring 3, circumferentially positioned by a positioning pin, and axially fixed by a rubber retaining ring 29. The outer rotor core 13 is installed on the inner side of the first outer ring 7 and the second outer ring 11, and axially fixed by screws. The permanent magnets 14 are evenly distributed on the inner side of the outer rotor core 13, and axially limited by the first housing and the second housing. The motor windings 15 are located on the teeth of the inner stator core 12.

[0030] The radial magnetic levitation system includes radial stator cores 16, radial rotor cores 17, radial displacement sensors 18, radial sensor detection rings 19, and radial windings 20. It mainly comprises four radial stator cores 16, one radial rotor core 17, four radial displacement sensors 18, and one radial sensor detection ring 19. The radial stator cores 16 are evenly distributed and installed inside the outer ring 3 of the bracket, spaced 90° apart. They are circumferentially positioned by locating pins and axially fixed by screws. Every two radial stator cores 16 spaced 180° apart form a group, resulting in two groups of radial stator cores 16. Figure 3 As shown, when the radial rotor core moves downward, the winding current corresponding to the radial stator core below the radial rotor core decreases, i.e., the electromagnetic force decreases, while the winding current corresponding to the radial stator core above the radial rotor increases, i.e., the electromagnetic force increases. The two radial stator cores form a group and are controlled differentially. The generated electromagnetic force causes the radial rotor to move upward and return to the equilibrium position. The radial rotor core 17 is installed on the outside of the first inner ring 4 with an interference fit. The radial displacement sensors 18 are evenly installed in the through holes opened in the inner shaft 1 of the bracket, with a 90° interval between each pair. Every two radial displacement sensors 18 with a 180° interval form a group, and there are two groups of radial displacement sensors 18. Each radial displacement sensor 18 corresponds to one radial stator core 16. The radial sensor detection ring 19 is installed on the inside of the first inner ring 4 with an interference fit. The radial winding 20 is located on the teeth of the radial stator core 16. The function of the radial sensor detection ring is to act as the detection object of the radial sensor to determine the radial displacement of the rotor part.

[0031] The axial magnetic levitation system includes an axial first stator core 21, an axial second stator core 22, an axial rotor core 23, an axial displacement sensor 24, and an axial winding 25. It mainly comprises six axial first stator cores 21, six axial second stator cores 22, two axial rotor cores 23, and six axial displacement sensors 24. The axial first stator cores 21 are evenly distributed and installed on both axial end faces of the outer ring 3 of the bracket, circumferentially positioned by locating pins and axially fixed by screws. Two axial first stator cores 21 located on the axial end faces of the outer ring 3 of the bracket and on the same axis constitute a group, resulting in three groups of axial first stator cores. Figure 4 As shown, when the rotor moves axially, the current in the first axial stator core winding closer to the axial rotor decreases, i.e., the electromagnetic force decreases; conversely, the current in the first axial stator core winding farther from the axial rotor core increases, i.e., the electromagnetic force increases. Two axial first stator cores on the same axis form a group, and differential control is used to return the axial rotor core to its equilibrium position. Each group of axial first stator cores contains two axial first stator cores, located on the end faces of both sides of the stator support and on the same axis. Each side of the stator support has three axial first stator cores, spaced 120° apart. Figure 5As shown in the diagram of the axial first stator core 21, the three axial first stator cores on the other side of the stator support end face can form three groups. The axial second stator cores 22 are evenly distributed on both axial end faces of the outer ring 3 of the support, circumferentially positioned by locating pins and axially fixed by screws. The three axial second stator cores 22 located on each axial end face of the outer ring 3 of the support form one group, resulting in two groups of axial second stator cores 22. The distribution of the axial second stator cores on each end face of the stator support is as follows: Figure 5 As shown in the diagram, the second axial stator cores 22 are spaced 120° apart. This distribution is primarily for coordination with the first axial stator cores, allowing for layout without affecting the first axial stator core layout. Since the control current is the same in the three second axial stator cores on each side of the stator support, the second axial stator cores adopt... Figure 5 The layout shown allows the electromagnetic force to be applied evenly to the corresponding axial rotor cores; the two axial rotor cores 23 are respectively installed on the inner sides of the first end face 5 and the second end face 9, and are axially fixed by screws; the axial displacement sensor 24 is installed in the groove opened in the axial first stator core 21, and the two axial displacement sensors 24 contained in each group of axial first stator cores 21 constitute a group, with a total of three groups of axial displacement sensors 24; the axial windings 25 are respectively located in the grooves opened in the axial first stator core 21 and the axial second stator core 22.

[0032] The mechanical protection bearings include a first mechanical protection bearing 26 and a second mechanical protection bearing 27. These bearings are angular contact ball bearings. The first mechanical protection bearing 26 and the second mechanical protection bearing 27 are respectively mounted on the outer sides of the first end face 5 and the second end face 9, and are axially fixed by end caps. When the radial displacement of the rotor is too large, the inner ring surface of the mechanical protection bearing contacts the cylindrical surface of the inner shaft 1 of the bracket to achieve radial protection; when the axial displacement of the rotor is too large, the inner ring end face of the mechanical protection bearing contacts the shoulder of the inner shaft 1 of the bracket to achieve axial protection.

[0033] In operation, the helicopter ducted tail rotor magnetic levitation electric drive configuration uses the radial magnetic levitation system to counteract the gravity of the helicopter ducted tail rotor section, which consists of the fuselage, the outer rotor core 13, the permanent magnet 14, the radial rotor core 17, the radial sensor detection ring 19, the axial rotor core 23, the first protective bearing 26, the second protective bearing 27, and the blades 28, thereby achieving radial levitation. The two sets of radial stator cores 16 in the radial magnetic levitation system are controlled using a differential mechanism. In each set of radial displacement sensors, if the displacement signal detected by one radial displacement sensor 18 decreases, the displacement signal of the other increases. Correspondingly, in the set of radial stator cores 16 corresponding to the set of radial displacement sensors 18, the electromagnetic force generated by the radial stator core 16 on the side with decreasing displacement decreases, and the electromagnetic force on the side with increasing displacement increases, causing the rotor to return to the radial equilibrium point. The two sets of radial stator cores 16 respectively control the helicopter ducted tail rotor section along... x Translation in the axial direction and y Translation in the axial direction.

[0034] The axial magnetic levitation system counteracts the force exerted by the air on the rotating blades 28, thus achieving axial levitation. The three sets of axial first stator cores 21 within the axial magnetic levitation system are controlled using a differential mechanism. Specifically, within the same set of axial first stator cores and corresponding axial displacement sensors, if the signal detected by one axial displacement sensor 24 decreases, the displacement signal of the other increases. Correspondingly, within the set of axial first stator cores 21 corresponding to that set of axial displacement sensors 24, the electromagnetic force generated by the axial first stator core 21 on the side with decreasing displacement decreases, while the electromagnetic force on the side with increasing displacement increases, causing the rotor to return to its axial equilibrium point. When the rotor moves axially, among the two axial displacement sensors 24 located on the same axis, if the rotor distance detected by one axial displacement sensor 24 decreases, the rotor distance detected by the other axial displacement sensor 24 will necessarily increase. The distance signal detected by the axial displacement sensor 24 is used as the input signal of the PID controller. The output of the PID controller is amplified and outputs a control current, thereby changing the electromagnetic force generated by the axial first stator core 21. The electromagnetic force decreases on the side where the rotor detection distance decreases, and increases on the side where the rotor detection distance increases, thus causing the rotor to return to the equilibrium position. The three sets of axial first stator cores 21 work together to control the helicopter ducted tail rotor section along... z Translation in the axial direction x Rotation in the axial direction and yRotation in the axial direction. The blades 28 are driven to rotate by the permanent magnet synchronous motor, thereby balancing the air's counter-torque on the rotor.

[0035] Under low-speed conditions, the electromagnetic force generated by the first axial stator core 21 can control the helicopter ducted tail rotor section along the rotor blades 28. z Translation in the axial direction x Rotation in the axial direction and y The axial rotation is possible, but the axial aerodynamic load is too large under conditions such as hovering. The first axial stator core 21 alone cannot generate sufficient load-bearing capacity. Therefore, a second axial stator core 22 is needed in addition to the first axial stator core 21. The two sets of second axial stator cores 22 in the axial magnetic levitation system are controlled using a differential mechanism. Each set of second axial stator cores 22 is uniformly controlled by the average value detected by three axial displacement sensors 24 on the same side, generating a rotational force along the axis. z An electromagnetic force in the axial direction, opposite to the direction of the air force acting on the rotor blades, is generated by the second axial stator core 22. This axial electromagnetic force is superimposed on the axial electromagnetic force generated by the first axial stator core 21, enhancing the electromagnetic force exerted on the helicopter ducted tail rotor section along the axis. z The system provides axial translational control capability. At low speeds, the detection distance of the axial displacement sensor is used as the input to the PID controller. The output of the PID controller, after being amplified, generates a controllable current to control the electromagnetic force of the first stator core along the axial direction, thereby controlling the rotor position. The axial displacement sensor then detects the rotor position again to achieve closed-loop control. The controllable electromagnetic forces generated by the three sets of first stator cores along the axial direction can control the rotor's translational motion. z Translation in the axial direction x Rotation in the axial direction and y Rotation along the axial direction; at higher speeds, based on the PID control of the first axial stator core, the average value detected by the three axial displacement sensors on the same side of the rotor is used as the input of the PID controller. The output of the PID controller is amplified to generate a controllable current to control the electromagnetic force of the second axial stator core. The axial displacement sensors detect the rotor position again to achieve closed-loop control, superimposing the electromagnetic force generated by the second axial stator core onto the first axial stator core, thereby improving the rotational speed along the axial direction. z The ability to control axial translation.

[0036] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A helicopter ducted tail rotor magnetic levitation electric drive configuration, characterized in that, The system includes a stator support, housing, blades, permanent magnet synchronous motor, radial magnetic levitation system, axial magnetic levitation system, and mechanical protection bearings. The stator support consists of an inner shaft (1), support bars (2), and an outer ring (3) from the inside out. The inner shaft (1) and the outer ring (3) are coaxial and are formed by the evenly distributed support bars (2). The evenly distributed support bars (2) reduce the weight of the stator support and provide wiring channels. The outer ring (3) has stepped surfaces, positioning pin holes, and threaded holes on its radial outer and inner sides to position and fix the stator part of the permanent magnet synchronous motor and the stator part of the radial magnetic levitation system. The outer ring (3) has positioning pin holes and threaded holes on its axial two-sided end faces to position and fix the stator part of the axial magnetic levitation system. The inner shaft (1) has through holes on its radial cylindrical surface and axial end face to lead out the wires of the permanent magnet synchronous motor, the radial magnetic levitation system, and the axial magnetic levitation system.

2. The helicopter ducted tail rotor magnetic levitation electric drive configuration according to claim 1, characterized in that, The housing includes a first housing and a second housing. The first housing consists of a first inner ring (4), a first end face (5), a first connecting strip (6), and a first outer ring (7) from the inside out. The second housing consists of a second inner ring (8), a second end face (9), a second connecting strip (10), and a second outer ring (11) from the inside out. The first inner ring (4) and the first outer ring (7) are coaxial. The first inner ring (4) and the first end face (5) are integral. The first inner ring (4) and the first end face (5) are integrally formed by the evenly distributed first connecting strips (6) and the first outer ring (7). The evenly distributed first connecting strips (6) can not only reduce the weight of the first housing but also provide a cooling channel. The airflow generated when the helicopter ducted tail rotor rotates passes through the gaps in the first connecting strips (6) to achieve cooling. The second inner ring (8) 8) Coaxial with the second outer ring (11), the second inner ring (8) and the second end face (9) are integrated, and the second outer ring (11) is formed by the evenly distributed second connecting strips (10). The evenly distributed second connecting strips (10) can not only reduce the weight of the second housing, but also provide a cooling channel; the axial end face of the first outer ring (7) and the axial end face of the second outer ring (11) are provided with through holes, and the rotor part of the permanent magnet synchronous motor is fixed by screws; the first end face (5) and the second end face (9) are provided with through holes, and the rotor part of the axial magnetic levitation system is fixed by screws; the radial outer side of the first outer ring (7) and the radial outer side of the second outer ring (11) are provided with evenly distributed grooves to realize the installation of the blade (28).

3. The helicopter ducted tail rotor magnetic levitation electric drive configuration according to claim 2, characterized in that, The permanent magnet synchronous motor includes an inner stator core (12), an outer rotor core (13), permanent magnets (14), and motor windings (15). The inner stator core (12) is coaxial with the outer rotor core (13). The inner stator core (12) is installed on the outer side of the bracket outer ring (3) and is circumferentially positioned by a positioning pin and axially fixed by a rubber retaining ring (29). The outer rotor core (13) is installed on the inner side of the first outer ring (7) and the second outer ring (11) and is axially fixed by screws. The permanent magnets (14) are evenly installed on the inner side of the outer rotor core (13) and are axially limited by the first housing and the second housing. The motor windings (15) are located on the teeth of the inner stator core (12).

4. The helicopter ducted tail rotor magnetic levitation electric drive configuration according to claim 3, characterized in that, The radial magnetic levitation system includes four radial stator cores (16), a radial rotor core (17), a radial displacement sensor (18), four radial sensor detection rings (19), and a radial winding (20). The radial stator cores (16) are evenly distributed and installed inside the outer ring (3) of the bracket. They are circumferentially positioned by positioning pins and axially fixed by screws. Every two radial stator cores (16) spaced 180° apart form a group, and there are two groups of radial stator cores (16). The radial rotor cores (17) are installed by interference fit. On the outside of the first inner ring (4), the radial displacement sensors (18) are evenly distributed and installed in the through holes opened in the inner shaft (1) of the bracket. Every two radial displacement sensors (18) spaced 180° apart form a group, and there are two groups of radial displacement sensors (18). Each radial displacement sensor (18) corresponds to a radial stator core (16). The radial sensor detection ring (19) is installed on the inside of the first inner ring (4) by interference fit. The radial winding (20) is located on the teeth of the radial stator core (16).

5. The helicopter ducted tail rotor magnetic levitation electric drive configuration according to claim 4, characterized in that, The axial magnetic levitation system includes six axial first stator cores (21), six axial second stator cores (22), two axial rotor cores (23), six axial displacement sensors (24), and axial windings (25). The axial first stator cores (21) are evenly distributed on both axial end faces of the outer ring (3) of the bracket, circumferentially positioned by positioning pins, and axially fixed by screws. Two axial first stator cores (21) located on both axial end faces of the outer ring (3) of the bracket and on the same axis form a group, and there are three groups of axial first stator cores. The axial second stator cores (22) are evenly distributed on both axial end faces of the outer ring (3) of the bracket, circumferentially positioned by positioning pins, and axially fixed by screws. The three axial second stator cores (22) located on each side of the outer ring (3) of the bracket form a group, and there are two groups of axial second stator cores (22). The two axial rotor cores (23) are respectively installed on the inner side of the first end face (5) and the second end face (9) and are axially fixed by screws. The axial displacement sensor (24) is installed in the groove opened in the axial first stator core (21). The two axial displacement sensors (24) contained in each group of axial first stator cores (21) form a group, and there are three groups of axial displacement sensors (24). The axial winding (25) is located in the groove opened in the axial first stator core (21) and the axial second stator core (22).

6. A helicopter ducted tail rotor magnetic levitation electric drive configuration according to claim 5, characterized in that, The mechanical protection bearing includes a first mechanical protection bearing (26) and a second mechanical protection bearing (27). The mechanical protection bearing adopts an angular contact ball bearing. The first mechanical protection bearing (26) and the second mechanical protection bearing (27) are respectively installed on the outside of the first end face (5) and the second end face (9) and are axially fixed by end caps. When the radial displacement of the rotor is too large, the inner ring surface of the mechanical protection bearing contacts the cylindrical surface of the inner shaft (1) of the bracket to achieve radial protection. When the axial displacement of the rotor is too large, the inner ring end face of the mechanical protection bearing contacts the shoulder of the inner shaft (1) of the bracket to achieve axial protection.

7. A helicopter ducted tail rotor magnetic levitation electric drive configuration according to claim 6, characterized in that, When the helicopter ducted tail rotor magnetic levitation electric drive configuration is in operation, the radial magnetic levitation system counteracts the gravity of the helicopter ducted tail rotor part, which consists of the housing, the outer rotor core (13), the permanent magnet (14), the radial rotor core (17), the radial sensor detection ring (19), the axial rotor core (23), the first mechanical protection bearing (26), the second mechanical protection bearing (27), and the blade (28), to achieve radial levitation. The axial magnetic levitation system also counteracts the force exerted by the air on the blade (28) when it rotates, to achieve axial levitation.

8. A helicopter ducted tail rotor magnetic levitation electric drive configuration according to claim 7, characterized in that, The radial magnetic levitation system contains two sets of radial stator cores (16) controlled by a differential mechanism. In each set of radial displacement sensors, if the displacement signal detected by one radial displacement sensor (18) decreases, the displacement signal of the other increases. Correspondingly, in the set of radial stator cores (16) corresponding to the set of radial displacement sensors (18), the electromagnetic force generated by the radial stator core (16) on the side with decreasing displacement decreases, and the electromagnetic force on the side with increasing displacement increases, causing the rotor to return to the radial equilibrium point. The two sets of radial stator cores (16) respectively control the helicopter ducted tail rotor section along... x Translation in the axial direction and y Translation in the axial direction.

9. A helicopter ducted tail rotor magnetic levitation electric drive configuration according to claim 8, characterized in that, The three sets of axial first stator cores (21) in the axial magnetic levitation system are controlled by differential operation. That is, in the same set of axial first stator cores and the corresponding set of axial displacement sensors, if the signal detected by one axial displacement sensor (24) decreases, the displacement signal of the other increases. Correspondingly, in the set of axial first stator cores (21) corresponding to the set of axial displacement sensors (24), the electromagnetic force generated by the axial first stator core (21) on the side with decreased displacement decreases, and the electromagnetic force on the side with increased displacement increases, so that the rotor returns to the axial equilibrium point. The three sets of axial first stator cores (21) work together to control the helicopter ducted tail rotor section along the axial direction. z Translation in the axial direction x Rotation in the axial direction and y Rotation in the axial direction.

10. A helicopter ducted tail rotor magnetic levitation electric drive configuration according to claim 9, characterized in that, When the rotor blades (28) operate at low speeds, the electromagnetic force generated by the axial first stator core (21) can control the helicopter ducted tail rotor section along the direction of rotation. z Translation in the axial direction x Rotation in the axial direction and y When the axial aerodynamic load is too large under conditions such as hovering, the axial second stator core (22) is used on the basis of the first axial stator core (21). The two sets of the second axial stator cores (22) contained in the axial magnetic levitation system are controlled by differential control. Each set of the second axial stator cores (22) is uniformly controlled by the average value detected by three axial displacement sensors (24) on the same side, generating rotation along the axis. z The electromagnetic force in the axial direction and opposite to the direction of the air force acting on the blades, the axial electromagnetic force generated by the second axial stator core (22) is superimposed on the axial electromagnetic force generated by the first axial stator core (21), thereby enhancing the electromagnetic force on the helicopter ducted tail rotor section along the axis. z The ability to control axial translation.

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