WO2015027409A1

WO2015027409A1 - Magnetic suspension flywheel motor

Info

Publication number: WO2015027409A1
Application number: PCT/CN2013/082455
Authority: WO
Inventors: 汪云涛; 孔翔; 王琳; 饶建红; 王晶菡; 宁蜀悦; 张臣; 李铁才
Original assignee: 深圳航天科技创新研究院
Priority date: 2013-08-28
Filing date: 2013-08-28
Publication date: 2015-03-05

Abstract

A magnetic suspension flywheel motor, the flywheel rotor assembly (1) thereof being a disc structure, and supported by at least one central bearing (10) and at least one set of magnetic suspension bearings; upper and lower rotor magnetic steel sheets (2, 3) and upper and lower stator PCB windings (8, 9) are disposed between the central bearing and the magnetic suspension bearings. The magnetic suspension flywheel motor combines a permanent magnet motor, a flywheel and magnetic suspension bearings, has a small size and light weight, and improves the performance of the flywheel motor.

Description

Magnetic suspension flywheel motor

Technical field

The invention relates to the field of electric machines, and in particular to a magnetic suspension flywheel motor.

Background technique

The conventional permanent magnet flywheel motor is composed of a permanent magnet motor and a flywheel body, and has a cumbersome structure. The permanent magnet motor drives the flywheel body to generate a momentum of JΩ, which can be used for energy storage, stable attitude or reaction control. The permanent magnet flywheel motor is required to have small loss, smooth rotation, small volume, and light weight.

However, the conventional permanent magnet flywheel motor has a bulky structure, its stator is slotted, and there is a cogging torque. The stator core generates iron loss and additional eddy current resistance torque when the motor rotates at a high speed. The friction torque and service life of the bearing are constrained. Flywheel motor performance issues.

Summary of the invention

In view of the above drawbacks of the prior art, the present invention provides a magnetic suspension flywheel motor to solve the problems of large loss and short life of the conventional permanent magnet flywheel motor.

The magnetic suspension flywheel motor of the present invention comprises a flywheel rotor assembly and a stator assembly, wherein the flywheel rotor assembly is a disc structure, wherein a swing center of the flywheel rotor assembly is sleeved on at least one center bearing adjacent to the flywheel rotor At least one set of magnetic suspension bearings is disposed at an edge of the component; an upper rotor magnetic steel piece and a lower rotor magnetic steel piece are respectively disposed on upper and lower surfaces of the flywheel rotor assembly between the central bearing and the magnetic suspension bearing, The upper and lower rotor magnetic steel sheets are respectively formed into a ring structure, and the respective magnetic steel sheets have a magnetic pole number of 2P, wherein P is a magnetic pole pair; the stator assembly includes an upper stator assembly located at an upper portion of the upper rotor magnetic steel sheet, And a lower stator assembly located at a lower portion of the lower rotor magnet piece; a lower surface of the upper stator assembly is provided with an upper stator yoke, and a lower surface of the upper stator yoke is provided with an upper stator PCB winding; the lower stator The upper surface of the assembly is provided with a lower stator yoke, and the upper surface of the lower stator yoke is provided with a lower stator PCB winding.

In the present invention, each of the magnetic suspension bearings includes an upper magnetic suspension rotating magnetic steel piece and a lower magnetic suspension rotating magnetic steel piece disposed on upper and lower surfaces of the flywheel rotor assembly, and an upper magnetic suspension static magnetic field disposed on a lower surface of the upper stator assembly. a steel sheet, and a lower magnetic suspension static magnetic steel sheet disposed on an upper surface of the lower stator assembly; the upper magnetic suspension rotating magnetic steel sheet and the upper magnetic suspension static magnetic steel sheet are opposite in polarity, mutually repulsive The force is opposite to the same polarity between the lower magnetic suspension rotating magnetic steel sheet and the lower magnetic suspension static magnetic steel sheet, and mutually repulsive forces are generated.

In a preferred embodiment of the present invention, the upper and lower magnetic suspension rotating magnetic steel sheets and the upper and lower magnetic suspension static magnetic steel sheets each adopt a circular plastic magnetic steel sheet of 0.5 to 5 mm, and the difference between the outer diameter D2 and the inner diameter D1 should be less than 20 mm. .

In a preferred embodiment of the invention, two sets of magnetic suspension bearings are provided, arranged radially between the two, and the distance H between the two should be greater than 2 mm, in this embodiment greater than 4 mm.

In a preferred embodiment of the present invention, a working gap between the upper magnetic suspension rotating magnetic steel sheet and the upper magnetic suspension static magnetic steel sheet, and between the lower magnetic suspension rotating magnetic steel sheet and the lower magnetic suspension static magnetic steel sheet is 0.15 to 5 mm. .

In a preferred embodiment of the invention, the upper and lower ends of the center bearing are provided with upper and lower corrugated washers and lower corrugated washers.

In a preferred embodiment of the invention, the upper and lower stator yokes are made of a plastic soft magnetic material or a ferrite soft magnetic material.

In a preferred embodiment of the present invention, the upper and lower rotor magnetic steel sheets have a thickness of 0.5 to 5 mm; the stator PCB windings are full-length windings, and uniformly distributed with Z=2 Pm windings, and the basic parameters of the motor should satisfy: πD/ 2P ≤ 40mm, where D is the average diameter of the annular magnetic steel sheet, Z is the number of virtual slots of the motor, and m is the number of phases of the motor.

In a preferred embodiment of the present invention, the motor is a three-phase permanent magnet motor, wherein m=3, Z=2Pm=6P, and the U, V, W three-phase windings form a three-phase independent coil winding, or the neutral line is connected to the Y connection mode. .

It can be seen from the above technical solution that the present invention combines a permanent magnet motor, a flywheel, and a magnetic suspension bearing, and the entire magnetic suspension flywheel motor has a remarkable feature of small size and light weight. Among them, the sheet magnetic steel and the sheet soft magnetic material and structure are used to eliminate the small cogging positioning torque and the eddy current loss of the stator core. The use of magnetic levitation greatly reduces the mechanical friction, so that the central bearing can be axially idling, the friction torque is small and the service life is very long. The magnetic suspension flywheel motor of the present invention fully optimizes the conventional performance.

DRAWINGS

Figure 1 is a cross-sectional view of a magnetic suspension flywheel motor in a preferred embodiment of the present invention;

Figure 2 is a schematic view showing the structure of the magnetic suspension bearing shown in Figure 1 and the magnetic lines of force generated by the repulsive magnetic field;

3 is a schematic view showing the stator winding of the PCB of the magnetic suspension flywheel motor shown in FIG. 1, wherein the three-phase windings are evenly distributed along the circumference at an electrical angle of 120°.

detailed description

The present invention will be further described with reference to the accompanying drawings and embodiments. In the preferred embodiment shown in FIGS. 1 to 3: 1 is a flywheel rotor assembly, 2 is an upper rotor magnet piece, and 3 is a lower rotor magnet piece, 4 Is the upper magnetic suspension rotating magnetic steel sheet, 41 is the upper magnetic suspension static magnetic steel sheet, 5 is the lower magnetic suspension rotating magnetic steel sheet, 51 is the lower magnetic suspension static magnetic steel sheet, 6 is the upper stator assembly, 7 is the lower stator assembly, 8 is the upper part The stator PCB windings, 81 is the upper stator yoke, 9 is the lower stator PCB winding, 91 is the lower stator yoke, 10 is the center bearing, 101 is the upper and lower corrugated washer of the center bearing, and 11 is the housing of the magnetic suspension flywheel motor.

As shown on the right side of FIG. 1, the flywheel rotor assembly 1 has a disk shape, and the upper rotor magnetic steel sheet 2 and the lower rotor magnetic steel sheet 3 are respectively disposed on the surface thereof, and the upper and lower rotor magnetic steel sheets are arranged. It is a ring structure and is symmetrical to each other with a magnetic pole number of 2P.

The upper stator yoke 81 is provided on the inner side of the upper stator assembly 6, and then the upper stator PCB winding 8 is provided and held in rotational opposition with the upper rotor magnetic steel sheet 2 of the flywheel rotor assembly 1. The lower stator assembly 7 is provided with a lower stator yoke 91 on the inner side, and then a lower stator PCB winding 9 is provided and is pivotally opposed to the lower rotor magnet piece 3 of the flywheel rotor assembly 1.

The center of rotation of the motor is the center bearing 10, which functions to achieve radial support. Upper and lower corrugated washers and a lower corrugated washer 101 are provided at the upper and lower ends of the center bearing 10.

At a position away from the center bearing 10 (i.e., near the edge of the flywheel rotor assembly 1), an annular magnetic bearing is also provided, which functions to achieve axial support. That is to say, Figure 1 shows only a partial cross-sectional structure, the dotted line on the right side is the center line, and the cross-sectional view is the left-right symmetrical structure; it is conceivable that the A-direction view of Figure 1 should be a center bearing 10 is the center of the circular structure.

As shown in the left side of Fig. 1, a magnetic suspension bearing includes an upper magnetic suspension rotating magnetic steel sheet 4 on the upper surface of the flywheel rotor assembly 1, and a lower magnetic suspension rotating magnetic steel sheet 5 on the lower surface of the flywheel rotor assembly 1, which is located inside the stator assembly 6. The upper magnetic suspension static magnetic steel sheet 41 and the lower magnetic suspension static magnetic steel sheet 51 located inside the stator assembly 7. Wherein, the upper magnetic suspension rotating magnetic steel sheet 4 and the upper magnetic suspension static magnetic steel sheet 41 are opposite in opposite polarity, for example, N pole to N pole, or S pole to S pole, and a repulsive force is generated between the two; The lower magnetic suspension rotating magnetic steel sheet 55 and the lower magnetic suspension static magnetic steel sheet 51 are also opposed to each other with the same polarity.

The upper and lower magnetic suspension rotating magnetic steel sheets and the upper and lower magnetic suspension static magnetic steel sheets are all made of 0.5 to 5 mm annular plastic magnetic steel sheets, and the difference between the outer diameter and the inner diameter should be less than 20 mm, which is less than 5 mm in this embodiment. In the embodiment shown in Figure 1, two sets of magnetic suspension bearings are provided, arranged radially between them, and the distance between the two should be greater than 2 mm. In the specific implementation, only one set of magnetic suspension bearings or three or more sets of magnetic suspension bearings may be provided.

The flywheel rotor assembly 1 is radially constrained by the central bearing 10 of the motor and axially supported by the magnetic suspension bearing. In a gravity free environment, the flywheel rotor assembly 1 will be suspended in the geometric center of the motor and free to rotate. In the gravity environment, the axial position of the flywheel rotor assembly 1 is determined by three factors: the restoring force of the magnetic suspension bearing, the restoring force of the corrugated washer 101, and the gravity. When the restoring force of the magnetic suspension bearing is much larger than the gravity, the axial position deviation of the flywheel rotor assembly 1 is negligible.

In this embodiment, the flywheel rotor assembly 1, the stator assemblies 6, 7 and the housing 11 together form a magnetic suspension flywheel motor as a whole. The magnetic suspension flywheel motor is a double stator and a double rotor motor, making full use of the entire space of the motor. The disc-shaped flywheel rotor assembly 1 has a symmetrical structure, a smooth surface, and a small air resistance during the rotation of the motor cavity.

As shown in FIG. 2, in the embodiment, the working gap δ between the upper magnetic suspension rotating magnetic steel sheet and the upper magnetic suspension static magnetic steel sheet, and between the lower magnetic suspension rotating magnetic steel sheet and the lower magnetic suspension static magnetic steel sheet is 0.15 ~ 5mm.

In a specific implementation, the upper and lower stator yokes are made of a plastic soft magnetic material or a ferrite soft magnetic material. The upper and lower rotor magnetic steel sheets have a thickness of 0.5 to 5 mm.

As shown in Figure 3, the stator PCB windings are full-length windings, and are uniformly distributed with Z=2Pm windings. The basic parameters of the motor should be: πD/2P≤40mm, where D is the average diameter of the annular magnetic steel sheet, and Z is the motor. The number of virtual slots, m is the number of phases of the motor. The motor shown in Fig. 3 is a three-phase permanent magnet motor, wherein m=3, Z=2Pm=6P, and the U, V, W three-phase windings form a three-phase independent coil winding, or the neutral line is connected in a Y connection manner.

The invention combines a permanent magnet motor, a flywheel and a magnetic suspension bearing, and the whole magnetic suspension flywheel motor has the remarkable characteristics of small volume and light weight. Among them, the sheet magnetic steel and the sheet soft magnetic material and structure are used to eliminate the small cogging positioning torque and the eddy current loss of the stator core. The use of magnetic levitation greatly reduces the mechanical friction, so that the central bearing can be axially idling, the friction torque is small and the service life is very long. The magnetic suspension flywheel motor of the present invention fully optimizes the conventional performance.

The magnetic suspension flywheel of the invention can be used as an energy storage flywheel of an energy storage system, and can be used for a stable attitude device or a space reaction flywheel control system.

Claims

A magnetic suspension flywheel motor comprising a flywheel rotor assembly and a stator assembly, the flywheel rotor assembly being a disc structure, wherein a swing center of the flywheel rotor assembly is sleeved on at least one center bearing adjacent to the flywheel At least one set of magnetic suspension bearings is disposed at an edge of the rotor assembly; and upper and lower surfaces of the flywheel rotor assembly between the central bearing and the magnetic suspension bearing are respectively provided with an upper rotor magnetic steel piece and a lower rotor magnetic steel piece, respectively The upper and lower rotor magnetic steel sheets are respectively formed into a ring structure, and the respective magnetic steel sheets have a magnetic pole number of 2P, wherein P is a magnetic pole number; the stator assembly includes an upper stator assembly located at an upper portion of the upper rotor magnetic steel sheet And a lower stator assembly located at a lower portion of the lower rotor magnet piece; a lower surface of the upper stator assembly is provided with an upper stator yoke, and a lower surface of the upper stator yoke is provided with an upper stator PCB winding; the lower portion The upper surface of the stator assembly is provided with a lower stator yoke, and the upper surface of the lower stator yoke is provided with a lower stator PCB winding.
A magnetic levitation flywheel motor according to claim 1, wherein each of said magnetic levitation bearings comprises an upper magnetic levitation rotating magnetic steel piece and a lower magnetic levitation rotating magnetic steel piece disposed on upper and lower surfaces of said flywheel rotor assembly, An upper magnetic suspension static magnetic steel sheet on a lower surface of the upper stator assembly, and a lower magnetic suspension static magnetic steel sheet disposed on an upper surface of the lower stator assembly; the upper magnetic suspension rotating magnetic steel sheet and the upper magnetic suspension static magnetic steel sheet are The same polarity is opposite to each other, and mutually repulsive force is generated; the lower magnetic suspension rotating magnetic steel sheet and the lower magnetic suspension static magnetic steel sheet are opposite in polarity, and mutually generate a repulsive force.
The magnetic levitation flywheel motor according to claim 2, wherein the upper and lower magnetic suspension rotating magnetic steel sheets and the upper and lower magnetic suspension static magnetic steel sheets each adopt a circular plastic magnetic steel sheet of 0.5 to 5 mm, and the outer diameter thereof is The difference in inner diameter is less than 20 mm.
A magnetic levitation flywheel motor according to claim 3, wherein two sets of magnetic levitation bearings are provided, the two are arranged in a radial direction, and the distance between the two should be greater than 2 mm.
A magnetic levitation flywheel motor according to claim 2, wherein said upper magnetic levitation rotating magnetic steel sheet and said upper magnetic levitation static magnetic steel sheet, and said lower magnetic levitation rotating magnetic steel sheet and lower magnetic levitation static magnetic steel sheet The working gap between the two is 0.15 to 5 mm.
A magnetic levitation flywheel motor according to claim 1, wherein upper and lower ends of said center bearing are provided with upper and lower corrugated washers and lower corrugated washers.
A magnetic levitation flywheel motor according to claim 1, wherein said upper and lower stator yokes are made of a plastic soft magnetic material or a ferrite soft magnetic material.
The magnetic levitation flywheel motor according to claim 1, wherein the upper and lower rotor magnetic steel sheets have a thickness of 0.5 to 5 mm; the stator PCB windings are full-length windings, and uniformly distributed with Z=2 Pm windings. The basic parameters of the motor should be: πD/2P ≤ 40mm, where D is the average diameter of the annular magnetic steel sheet, Z is the number of virtual slots of the motor, and m is the number of phases of the motor.
The magnetic levitation flywheel motor according to claim 8, wherein the motor is a three-phase permanent magnet motor, wherein m=3, Z=2Pm=6P, and the U, V, W three-phase windings form a three-phase independent coil winding Or the middle line is connected to the Y connection mode.