A ducted active magnetic levitation rotor

Abstract

The present invention discloses a ducted active magnetic suspension rotor, which is composed of a permanent magnet motor, a ducted propeller disk, an active magnetic suspension bearing system and a support frame. The permanent magnet motor is arranged at the center of the rotor propeller disk, and includes a motor stator, a motor rotor and a protective bearing. The motor rotor is fixedly connected to the blades to drive the propeller disk to rotate; the ducted propeller disk is composed of blades, propeller disk bushings and magnetic conductive rings; the active magnetic suspension bearing system is composed of N radial magnetic suspension bearings and M pairs of axial magnetic suspension bearings evenly arranged along the circumference of the propeller disk; the support frame is used to fix the motor stator and the magnetic suspension bearing system, and is connected to the fuselage to transmit the propeller disk thrust. The present invention improves the aerodynamic efficiency of the rotor, reduces the bending moment of the blades, and increases the life of the rotor. At the same time, the ducted propeller disk is supported by a magnetic suspension bearing, so that the propeller disk can be operated friction-free, wear-free and efficiently, and a feasible solution is provided for the outer ring support of the propeller disk.

Description

Technical Field

[0001] The present invention relates to the fields of electric transmission, magnetic suspension and aerodynamics, and in particular to a ducted active magnetic suspension rotor. Background Art

[0002] The blades of a traditional ducted rotor are fixedly connected to the motor rotor, and a mechanical bearing is used to connect the motor stator and the motor rotor. The lift generated by the rotation of the blades is transmitted from the motor rotor to the motor stator through the mechanical bearing, and then transmitted to the fuselage by the support beam fixed to the motor stator. Due to the maximum linear velocity limit of the mechanical bearing, in a traditional ducted rotor system, the mechanical bearing can only be installed at the motor in the center of the propeller disc (where the linear velocity is much smaller than the linear velocity of the outer side of the propeller disc) to transmit the lift of the blades, that is, the central force transmission configuration of the propeller disc. In this configuration, in order to prevent the blades from being severely deformed by the bending moment load generated by the lift, the blade load is often reasonably distributed by reducing the area of ​​the outer section of the blade, and there is a gap between the blade tip and the duct wall. Therefore, the traditional ducted rotor with a central force transmission configuration of the propeller disc cannot fully utilize the lift advantage brought by the high linear velocity of the blade tip.

[0003] The force transmission configuration on the outer side of the propeller disc connects the blade to the duct wall, so that the lift generated by the blade is transmitted to the fuselage through the outer side of the propeller disc. This configuration can reduce the blade bending moment load and improve aerodynamic efficiency by more than 15%. However, installing traditional bearings on the outer side of the propeller disc will cause the bearing size to be too large and the weight to increase significantly. In addition, traditional bearings cannot withstand the high linear speed on the outer side of the propeller disc. Therefore, a support method is needed to meet the high linear speed support requirements of the outer side of the propeller disc while having a lighter weight.

[0004] Active magnetic bearings achieve contactless suspension of the rotor by applying controllable electromagnetic force to the rotor. Therefore, the maximum linear speed of the rotor supported by the magnetic bearings is much higher than that of traditional bearings (the Dn value is more than 3 times higher than that of traditional bearings). At the same time, it has the characteristics of no friction, no need for lubrication, long life, high efficiency, and support for active vibration control. It is widely used in industrial, civilian, and high-end military fields.

[0005] The introduction of magnetic bearings into ducted rotors overcomes the shortcoming of the low maximum speed that traditional bearings can withstand, making it possible to configure the force transmission on the outside of the propeller disc, that is, a ducted rotor configuration in which the active magnetic bearings arranged on the outside of the propeller disc support the rotor propeller disc in a contactless manner and transmit the thrust generated by the rotation of the blades. The power consumed by the magnetic bearings to support the propeller disc is only one-third of the friction power consumption of traditional bearings, and the noise of the rotor system can be greatly reduced. At the same time, the active magnetic levitation rotor system can suppress the influence of external interference through active vibration control, significantly improving the flight stability of the aircraft.

[0006] In summary, the ducted active magnetic levitation rotor system can greatly improve the rotor performance and achieve high-efficiency and high-reliability drive with a high thrust-to-weight ratio. Summary of the invention

[0007] The technical problem to be solved by the present invention is to provide a ducted magnetic levitation rotor in response to the defects of the background technology, so as to improve the mechanical efficiency and aerodynamic efficiency of the rotor system, reduce the noise of the rotor system, and improve the vibration problem of the rotor disc.

[0008] The present invention adopts the following technical solutions to solve the above technical problems:

[0009] A ducted active magnetic suspension rotor comprises a permanent magnet motor located at the center of a propeller disk, a ducted propeller disk, a support frame, N radial magnetic suspension bearings and M pairs of axial magnetic suspension bearings, wherein N and M are natural numbers greater than or equal to 1.

[0010] Furthermore, the ducted impeller disk includes blades, an impeller disk bushing and a magnetic conductive ring; wherein, the permanent magnet motor is arranged at the center of the impeller disk, and the motor rotor and the blades are fixedly connected; the cross-sectional area of ​​the blades gradually increases from the inside to the outside along the radial direction of the impeller disk, and is fixedly connected to the impeller disk bushing; the inner diameter of the impeller disk bushing is the same as the duct diameter of the fuselage, and is fixedly connected to the magnetic conductive ring.

[0011] Furthermore, the stator of the permanent magnet motor is made of laminated silicon steel sheets, and the motor stator is fixedly connected to the support frame; a protective bearing is installed between the motor stator and the motor rotor, and the protective bearing gap is smaller than the minimum air gap of the magnetic suspension bearing.

[0012] Furthermore, the radial magnetic bearing is composed of a radial magnetic bearing core, a magnetic bearing winding coil, a magnetic bearing coil sleeve, a radial rotor displacement sensor, a radial magnetic bearing seat and a radial magnetic bearing pressure plate; wherein, the magnetic pole of the radial magnetic bearing core is directly opposite to the radial surface of the magnetic conductive ring, and the radial magnetic bearing core and the magnetic conductive ring have a radial suspension gap; the radial magnetic bearing core and the radial magnetic bearing pressure plate are fixedly connected to the radial magnetic bearing seat by bolts; the magnetic bearing winding coil is fixedly connected to the radial magnetic bearing core by the magnetic bearing coil sleeve; the radial rotor displacement sensor is directly opposite to the magnetic conductive ring, and is fixedly connected to the radial magnetic bearing pressure plate through the mounting hole; the radial magnetic bearing seat is fixedly connected to the support frame by bolts.

[0013] Furthermore, the axial magnetic bearing is composed of a pair of axial magnetic bearing cores, magnetic bearing winding coils, magnetic bearing coil sleeves, a pair of axial rotor displacement sensors, axial magnetic bearing seats and a pair of axial magnetic bearing pressure plates; wherein, the magnetic poles of the axial magnetic bearing cores are directly opposite to the axial surface of the magnetic conductive ring, and there is an axial suspension gap between the axial magnetic bearing cores and the magnetic conductive ring; the axial magnetic bearing cores and the axial magnetic bearing pressure plates are fixedly connected to the axial magnetic bearing seats by bolts; the magnetic bearing winding coils are fixedly connected to the axial magnetic bearing cores by the magnetic bearing coil sleeves; the axial rotor displacement sensors are directly opposite to the magnetic conductive rings, and the axial displacement signals are detected by differential means, and the axial rotor displacement sensors are fixedly connected to the axial magnetic bearing pressure plates through mounting holes; and the axial magnetic bearing seats are fixedly connected to the support frame by bolts.

[0014] Furthermore, the support beam at the lower end of the support frame only provides the supporting force required to support the motor stator. The axial thrust generated by the rotation of the propeller disc is transmitted to the support frame through the axial magnetic bearing, and then the thrust is transmitted to the fuselage through the support frame.

[0015] Compared with the prior art, the present invention adopts the above technical solution and has the following technical effects:

[0016] 1. The active magnetic bearing is used to support the ducted propeller disc, and the power consumed is only one-third of the friction power consumption of traditional bearing support, which improves the range of the aircraft.

[0017] 2. Active magnetic bearings can reduce the impact of external interference on the ducted propeller disc through active vibration control, reduce the vibration transmitted to the aircraft body, and improve the flight stability of the aircraft.

[0018] 3. Improved the aerodynamic efficiency of the rotor system and increased the fatigue life of the blades. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the structure of the ducted active magnetic levitation rotor of the present invention.

[0020] Figure 2 It is a schematic diagram of the structure of the ducted impeller disc of the present invention.

[0021] Figure 3 It is a schematic diagram of the structure of the permanent magnet motor of the present invention.

[0022] Figure 4 It is a schematic diagram of the structure of the radial magnetic bearing of the present invention.

[0023] Figure 5 It is a schematic diagram of the structure of the axial magnetic bearing of the present invention. DETAILED DESCRIPTION

[0024] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings:

[0025] The present invention may be implemented in many different forms and should not be considered limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0026] like Figure 2 The diagram shows a schematic diagram of the structure of a ducted impeller disk. The impeller disk bushing (14) of the ducted impeller disk is made of aluminum alloy, and a stepped shaft is processed on the outer ring surface. The magnetic ring (7) is fixedly connected to the impeller disk bushing (14) by means of an interference fit shrink fit. The magnetic ring is made of high-performance soft magnetic material, and its cross-sectional area is slightly larger than the magnetic circuit cross-sectional area of ​​the radial and axial magnetic suspension bearing cores (15, 6). The blade (8) is fixedly connected to the motor rotor (16) and the impeller disk bushing (14).

[0027] like Figure 3 The schematic diagram of the structure of a permanent magnet motor is shown. The inner surface of the motor rotor (16) is affixed with a permanent magnet patch. The radial and axial gaps between the motor rotor (16) and the motor stator (9) are larger than the radial and axial suspension gaps between the radial and axial magnetic suspension bearing cores (15, 6) and the magnetic conductive ring (7). A protective bearing is installed between the motor rotor (16) and the motor stator (9). The radial and axial protection gaps are smaller than the radial and axial suspension gaps between the radial and axial magnetic suspension bearing cores (15, 6) and the magnetic conductive ring (7). The protective bearing is an angular contact ball bearing that can withstand radial and axial loads.

[0028] like Figure 4 The figure shows a schematic diagram of the structure of a radial magnetic bearing. The material of the radial magnetic bearing core (15) is a high-strength and high-performance soft magnetic material, and positioning holes are opened on both sides. The radial magnetic bearing seat (3) and the radial magnetic bearing pressure plate (1) are made of aluminum alloy and do not have magnetic conductivity. The front end of the radial magnetic bearing pressure plate (1) is provided with a sensor installation hole for installing a radial rotor displacement sensor (2). The radial rotor displacement sensor (2) is an eddy current sensor, and the sensor probe is directly opposite to the magnetic conductive ring (7), and can detect the radial displacement of the rotor in a non-contact manner.

[0029] like Figure 5The figure shows a schematic diagram of the structure of an axial magnetic bearing. The axial magnetic bearing core (6) is made of high-strength and high-performance soft magnetic material and has positioning holes on both sides. The upper and lower surfaces of the axial magnetic bearing seat (12) are provided with positioning installation grooves for installing the axial magnetic bearing core (6), which can ensure the installation accuracy of the axial magnetic bearing. The protruding end of the axial magnetic bearing pressure plate (10) is provided with a positioning hole for installing the axial rotor displacement sensor (4) and ensuring that the probe of the axial rotor displacement sensor (4) is directly opposite to the axial surface of the magnetic ring (7). The axial rotor displacement sensor (4) is an eddy current sensor. A pair of axial rotor displacement sensors (4) installed on the axial magnetic bearing use a differential method to calculate the axial displacement of the ducted impeller.

[0030] The working principle of active magnetic bearing is as follows:

[0031] The structure of the active magnetic bearing system mainly consists of five parts: stator, rotor, sensor, controller, and power amplifier. The active magnetic bearing detects the rotor displacement through a non-contact displacement sensor and feeds the displacement signal back to the controller. After the controller calculates, it outputs the appropriate control current to the stator electromagnet, thereby generating appropriate electromagnetic force to make the rotor suspend in the desired position.

[0032] It will be understood by those skilled in the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as those generally understood by those skilled in the art in the art to which the present invention belongs. It should also be understood that terms such as those defined in common dictionaries should be understood to have meanings consistent with the meanings in the context of the prior art, and will not be interpreted with idealized or overly formal meanings unless defined as herein.

[0033] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A ducted active magnetic levitation rotor, characterized in that: It includes a permanent magnet motor located at the center of the propeller disk, a ducted propeller disk, a support frame, and N radial magnetic bearings and M pairs of axial magnetic bearings, where N and M are natural numbers greater than or equal to 1; The ducted impeller disk comprises a blade (8), an impeller disk bushing (14) and a magnetic conductive ring (7); wherein the permanent magnet motor is arranged at the center of the impeller disk, and the motor rotor (16) is fixedly connected to the blade (8); the cross-sectional area of ​​the impeller disk (8) gradually increases from the inside to the outside along the radial direction of the impeller disk, and is fixedly connected to the impeller disk bushing (14); the inner diameter of the impeller disk bushing (14) is the same as the diameter of the fuselage duct, and is fixedly connected to the magnetic conductive ring (7); The permanent magnet motor stator (9) is made of laminated silicon steel sheets, and the motor stator (9) is fixedly connected to a support frame (13); a protective bearing (17) is installed between the motor stator (9) and the motor rotor (16), and the gap of the protective bearing (17) is smaller than the minimum air gap of the magnetic suspension bearing; The radial magnetic suspension bearing is composed of a radial magnetic suspension bearing core (15), a magnetic suspension bearing winding coil (5), a magnetic suspension bearing coil sleeve (11), a radial rotor displacement sensor (2), a radial magnetic suspension bearing seat (3) and a radial magnetic suspension bearing pressure plate (1); wherein the magnetic pole of the radial magnetic suspension bearing core (15) is directly opposite to the radial surface of the magnetic conductive ring (7), and the radial magnetic suspension bearing core (15) and the magnetic conductive ring (7) have a radial suspension gap; the radial magnetic suspension bearing core (15) and the radial magnetic suspension bearing pressure plate (1) are fixedly connected to the radial magnetic suspension bearing seat (3) by bolts; the magnetic suspension bearing winding coil (5) is fixedly connected to the radial magnetic suspension bearing core (15) by the magnetic suspension bearing coil sleeve (11); the radial rotor displacement sensor (2) is directly opposite to the magnetic conductive ring (7) and is fixedly connected to the radial magnetic suspension bearing pressure plate (1) by a mounting hole; and the radial magnetic suspension bearing seat (3) is fixedly connected to the support frame (13) by bolts; The axial magnetic suspension bearing comprises a pair of axial magnetic suspension bearing cores (6), a magnetic suspension bearing winding coil (5), a magnetic suspension bearing coil sleeve (11), a pair of axial rotor displacement sensors (4), an axial magnetic suspension bearing seat (12) and a pair of axial magnetic suspension bearing pressure plates (10); wherein the magnetic poles of the axial magnetic suspension bearing core (6) are directly opposite to the axial surface of the magnetic conductive ring (7), and an axial suspension gap is provided between the axial magnetic suspension bearing core (6) and the magnetic conductive ring (7); the axial magnetic suspension bearing core (6) and The axial magnetic suspension bearing pressure plate (10) is fixedly connected to the axial magnetic suspension bearing seat (12) by bolts; the magnetic suspension bearing winding coil (5) is fixedly connected to the axial magnetic suspension bearing iron core (6) by a magnetic suspension bearing coil sleeve (11); the axial rotor displacement sensor (4) is directly opposite to the magnetic conductive ring (7) and detects the axial displacement signal by differential mode; the axial rotor displacement sensor (4) is fixedly connected to the axial magnetic suspension bearing pressure plate (10) by a mounting hole; the axial magnetic suspension bearing seat (12) is fixedly connected to the support frame (13) by bolts; The support beam at the lower end of the support frame (13) only provides the support force required to support the motor stator (9), and the axial thrust generated by the rotation of the propeller disc is transmitted to the support frame (13) through the axial magnetic bearing, and then the thrust is transmitted to the fuselage through the support frame (13).

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