Bearingless permanent magnet synchronous motor

Abstract

The utility model relates to a bearingless permanent magnet synchronous motor. Comprising a quadrupole magnetic flux, a stator, a quadrupole torque winding Nx, a quadrupole torque winding Ny, a quadrupole torque winding Na and a quadrupole torque winding Nb, permanent magnets are arranged on the outer side of the quadrupole magnetic flux, a rotor core is arranged on the outer side of the permanent magnets, a permanent magnet A is arranged on the rotor core, stainless steel lantern rings are arranged on the outer sides of the rotor core and the permanent magnet A, and the quadrupole torque winding Nx and the quadrupole torque winding Ny are arranged on the outer sides of the stainless steel lantern rings. The quadrupole torque winding Na and the quadrupole torque winding Nb are arranged on the outer sides of the quadrupole torque winding Nx and the quadrupole torque winding Ny, and the stator is arranged on the outer sides of the quadrupole torque winding Na and the quadrupole torque winding Nb. According to the utility model, the failure rate of the motor is reduced, thereby prolonging the service life. The higher and more stable output torque is provided, and meanwhile stable operation of the motor is guaranteed. Active control over the motor rotor is achieved on five degrees of freedom, and due to the fact that a magnetic bearing is omitted, the axial length of the motor rotor and the reactive power loss of a system are further reduced.

Description

Technical Field

[0001] The utility model belongs to the technical field of motor equipment, and in particular relates to a bearingless permanent magnet synchronous motor. Background Art

[0002] The bearingless permanent magnet synchronous motor does not mean that it does not need bearings to support it, but it does not need to design or use special mechanical bearings, air bearings or liquid bearings. On the one hand, the bearingless permanent magnet synchronous motor has the advantages of non-contact, no lubrication and no wear of magnetic suspension bearings, and no mechanical noise. On the other hand, the motor speed can be very high and the power can be very large, which can break through the ultra-high speed and maximum power limit. It can be widely used in aerospace, power peak regulation, uninterruptible power supply, electric vehicles and many other fields.

[0003] The core technology of bearingless motors is the automatic control system technology, which is relatively backward in China. When the rated output power of the motor is >30KW, there are potential safety hazards, resulting in unqualified product quality; poor production efficiency, motor cycle life <1X10^6h, and poor anti-magnetic degeneration performance, resulting in inaccurate movements, increased position deviations, or failure to move normally. When the motor dynamic adjustment speed is >3 seconds, the driving accuracy is reduced, resulting in the problem of difficulty in accurately controlling the direction of the radial suspension force. Therefore, it is necessary to improve the utilization rate of permanent magnets per unit volume and high energy density.

[0004] In summary, the prior art has problems such as unstable motor operation sensitivity, high motor failure rate, short cycle life, axial length of the motor rotor and system loss. Summary of the invention

[0005] The purpose of this section is to summarize some aspects of the embodiments of the utility model and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the abstract of the specification and the name of the utility model to avoid blurring the purpose of this section, the abstract of the specification and the name of the utility model, and such simplifications or omissions cannot be used to limit the scope of the utility model.

[0006] Therefore, the purpose of the utility model is to provide a bearingless permanent magnet synchronous motor, which can solve the problems of unstable motor operation sensitivity, high motor failure rate, short cycle life, axial length of the motor rotor and system loss in the prior art.

[0007] In order to solve the above technical problems, the utility model provides a bearingless permanent magnet synchronous motor, which includes a four-pole magnetic flux, a stator, a four-pole torque winding Nx, a four-pole torque winding Ny, a four-pole torque winding Na, and a four-pole torque winding Nb. The four-pole magnetic flux is outside a permanent magnet, the permanent magnet is outside a rotor core, a permanent magnet A is on the rotor core, the rotor core and the permanent magnet A are outside a stainless steel collar, the four-pole torque winding Nx and the four-pole torque winding Ny are outside the stainless steel collar, the four-pole torque winding Na and the four-pole torque winding Nb are outside the four-pole torque winding Nx and the four-pole torque winding Ny, the four-pole torque winding Na and the four-pole torque winding Nb are outside the stator, and the four-pole torque winding Nx and the four-pole torque winding Ny are symmetrically distributed on both sides of the stainless steel collar. The four-pole torque winding Nx and the four-pole torque winding Ny are suspended outside the stainless steel collar.

[0008] By adopting the above technical solutions, this case uses rotor magnetic field oriented control to decouple the torque force and radial suspension force of the motor. In order to solve the problem of difficult to accurately control the direction of the radial suspension force, the sensitivity is controlled at 9dB through suspension force verification, and the dynamic adjustment displacement can reach 0.5mm. It provides a higher and more stable output torque while ensuring the stable operation of the motor.

[0009] Optionally, the stator, the stainless steel collar, and the rotor core are circular, and the distance from the stator to the stainless steel collar is greater than or equal to the distance from the stainless steel collar to the center of the circle.

[0010] In summary, the present invention has at least one of the following beneficial effects:

[0011] The magnetic bearing of the utility model can make the rotor suspend stably in the stator. During the suspension, we can perform high-precision five-degree-of-freedom magnetic control on it, ensuring that the sensitivity of the motor is stably controlled at 9dB.

[0012] The utility model reduces the failure rate of the motor, thereby increasing its service life, provides a higher and more stable output torque, and ensures the stable operation of the motor.

[0013] The motor of the utility model can realize active control of the motor rotor in five degrees of freedom, and because the magnetic bearing is cancelled, the axial length of the motor rotor and the reactive power loss of the system are further reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0015] Figure 1 A schematic diagram of the radial suspension force generation mechanism of a bearingless permanent magnet synchronous motor of the utility model;

[0016] List of figure symbols: 1: stator 2: magnetic pole 3: rectangular coordinate y 4: rotor core 5: stainless steel ring 6: permanent magnet 7: rectangular coordinate x 8: permanent magnet A 9: four-pole torque winding Na 10: four-pole magnetic flux 11: suspension force 12: i 13: U 14: four-pole torque winding Nb 15: four-pole torque winding Nx 16: four-pole torque winding Ny. DETAILED DESCRIPTION

[0017] The following is combined with Figure 1 The utility model is further described in detail.

[0018] Embodiment 1, refer to Figure 1 In order to solve the problems of unstable motor operation sensitivity, high motor failure rate, short cycle life, axial length of the motor rotor and system loss in the prior art, this embodiment is designed to solve the problems of unstable motor operation sensitivity, high motor failure rate, short cycle life, and low cycle life in the prior art. The utility model discloses a bearingless permanent magnet synchronous motor, comprising a four-pole magnetic flux 10, a stator 1, a four-pole torque winding Nx15, a four-pole torque winding Ny16, a four-pole torque winding Na9, and a four-pole torque winding Nb14. The outer side of the four-pole magnetic flux 10 is a permanent magnet 6, the outer side of the permanent magnet 6 is a rotor core 4, a permanent magnet A8 is on the rotor core 4, the outer sides of the rotor core 4 and the permanent magnet A8 are stainless steel collars 5, the four-pole torque winding Nx15 and the four-pole torque winding Ny16 are outside the stainless steel collar 5, the four-pole torque winding Na9 and the four-pole torque winding Nb14 are outside the four-pole torque winding Nx15 and the four-pole torque winding Ny16, the stator 1 is outside the four-pole torque winding Na9 and the four-pole torque winding Nb14, and the four-pole torque winding Nx15 and the four-pole torque winding Ny16 are centrally symmetrically distributed on both sides of the stainless steel collar 5. The stator 1, the stainless steel collar 5, and the rotor core 4 are circular. The four-pole torque winding Nx and the four-pole torque winding Ny are suspended outside the stainless steel collar. The distance from the stator 1 to the stainless steel collar 5 is greater than or equal to the distance from the stainless steel collar 5 to the center of the circle.

[0019] Specific implementation principle: When the rotor is in the center position, the symmetrical four-pole magnetic flux 10 Generated by four-pole permanent magnets, when the motor is running at no load, the four-pole torque winding Na9 and the four-pole torque winding Nb14 The quadrupole magnetic flux 10 generated by the current in the bearingless motor is small and can be ignored. The electromagnetic torque output by the bearingless motor is based on the Lorentz force, which is the same as that of an ordinary permanent magnet synchronous motor. The motor also has quadrupole torque windings Nx15 and Ny16. , the rectangular coordinates in the figure x7 and rectangular coordinates y3 Pointing to the four-pole torque winding Nx15 and the four-pole torque winding Ny16 respectively The direction of the generated magnetomotive force. If the four-pole torque winding Nx15 and the four-pole torque winding Ny16 When there is no current flowing through the quadrupole magnetic flux 10, the quadrupole magnetic flux 10 is balanced, and the air gap magnetic flux corresponding to the pole 2 is equal, and no radial suspension force is generated. When a positive current flows through the quadrupole torque winding Nx15, the generated two-pole magnetic flux is as follows: Figure 1 As shown in the figure, the air gap flux under each pole is no longer equal, the air gap flux density of pole 3 decreases, while the air gap flux density of pole stator 1 increases. The unbalanced air gap flux causes the radial suspension force to cause the rotor to move in the rectangular coordinates. x7 If the current passing through the four-pole torque winding Nx15 is negative, the radial suspension force will cause the rotor to move in the rectangular coordinate direction. x7 Similarly, the current in the four-pole torque winding Ny16 will produce a y3 Therefore, based on the motor excitation flux, by controlling the four-pole torque winding Nx15 and the four-pole torque winding Ny16 The current in the rotor can control the magnitude and direction of the radial suspension force, thereby achieving stable suspension of the rotor.

[0020] The above are all preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention. Therefore, any equivalent changes made based on the structure, shape, and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A bearingless permanent magnet synchronous motor, characterized in that: The invention comprises a four-pole magnetic flux (10), a stator (1), a four-pole torque winding Nx (15), a four-pole torque winding Ny (16), a four-pole torque winding Na (9), and a four-pole torque winding Nb (14); the outer side of the four-pole magnetic flux (10) is a permanent magnet (6); the outer side of the permanent magnet (6) is a rotor core (4); a permanent magnet A (8) is on the rotor core (4); the outer sides of the rotor core (4) and the permanent magnet A (8) are stainless steel collars (5); the four-pole torque winding Nx (15) and the four-pole torque winding Ny (16) are outer sides of the stainless steel collars (5); the four-pole torque winding Na (9) and the four-pole torque winding Nb (14) are outer sides of the four-pole torque winding Nx (15) and the four-pole torque winding Ny (16); and the outer sides of the four-pole torque winding Na (9) and the four-pole torque winding Nb (14) are the stator (1).

2. A bearingless permanent magnet synchronous motor according to claim 1, characterized in that: The four-pole torque winding Nx (15) and the four-pole torque winding Ny (16) are centrally symmetrically distributed on both sides of the stainless steel sleeve (5).

3. The bearingless permanent magnet synchronous motor according to claim 1, characterized in that: The four-pole torque winding Nx (15) and the four-pole torque winding Ny (16) are suspended outside the stainless steel ring (5).

4. The bearingless permanent magnet synchronous motor according to claim 1, characterized in that: The stator (1), the stainless steel sleeve ring (5), and the rotor core (4) are circular.

5. The bearingless permanent magnet synchronous motor according to claim 1, characterized in that: The distance from the stator (1) to the stainless steel sleeve ring (5) is greater than or equal to the distance from the stainless steel sleeve ring (5) to the center of the circle.

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