WO2019161623A1

WO2019161623A1 - Cylindrical arc permanent magnet motor for use in large-caliber astronomical telescope

Info

Publication number: WO2019161623A1
Application number: PCT/CN2018/088137
Authority: WO
Inventors: 房淑华; 盘真保; 薛松寒; 阳辉; 林鹤云; 王海涛
Original assignee: 东南大学
Priority date: 2018-02-26
Filing date: 2018-05-24
Publication date: 2019-08-29
Also published as: CN108400662A

Abstract

The present invention relates to a cylindrical arc permanent magnet motor for use in a large-caliber astronomical telescope. The cylindrical arc permanent magnet motor comprises a rotor part (I) and a stator part (II), the rotor part (I) being sleeved on the outer surface of the stator part (II). The rotor part consists of three cylindrical rotor modules, each cylindrical rotor module is constituted by a cylindrical rotor iron core and a cylindrical armature winding (4), and the cylindrical armature winding (4) is arranged in a groove at the inner circumference of the corresponding cylindrical rotor iron core, where the cylindrical rotor iron cores comprise rotor back yokes (1), rotor teeth (2), rotor grooves (3), and, the rotor teeth and the rotor grooves are arranged on inner hole walls of the rotor back yokes. The stator part is constituted by a stator iron core (5) and an alternating polarity permanent magnet array (6) affixed to the exterior of the stator iron core. The present invention allows the pitch axis of the telescope to freely rotate within a 180° range; secondly, the annular armature windings increase the area of air gaps, thus increasing the torque density and torque stability of the motor.

Description

Cylindrical arc permanent magnet motor for large diameter astronomical telescope

Technical field

The invention relates to a cylindrical arc permanent magnet motor for a large-diameter telescope, which can be used for high-precision sports where the pitch axis of the astronomical telescope rotates freely within a range of 180°.

Background technique

The traditional transmission methods of large-caliber telescopes mainly include worm gear drive, gear drive, friction drive and torque motor coaxial installation drive. These traditional transmission modes play an important role in the development of telescopes, but there are backlashes. The tooth surface contact stress is large, and the high frequency tooth shape error is large. Therefore, with the development of science and technology, in order to solve the above shortcomings, the European Southern Observatory took the lead in proposing a transmission method using a spliced arc motor. Around this transmission mode, many research institutions and scholars at home and abroad have carried out related research work and achieved significant The result. The Chinese patent (Application No.: CN92223750.6) discloses an arc-shaped motor which is composed of an arc-shaped stator and a steel flywheel rotor, which is realized by the rotating magnetic field of the stator and the magnetic field interaction generated by the induced current of the rotor. Rotational motion of the rotor. Chinese patent (application number: CN200710134531.X) discloses an ultra-low-speed precision arc motor for large-scale astronomical telescopes, and the team also discloses a large-scale telescope permanent magnet synchronous motor control system and method thereof under strong wind-borne disturbance (application No.: CN201410169656.6). Compared with the conventional method, the transmission mode using the arc motor has the advantages of less intermediate transmission links, simple structure, easy maintenance and high transmission efficiency, but the torque density of the motor is not large enough due to the end of the winding of the above-mentioned arc motor itself. In addition, the cogging effect, edge effect, and high-order harmonic current caused by the asymmetry of the three-phase winding of the motor itself will cause the motor to generate positioning torque and torque fluctuation, which will weaken the smooth and reliable operation of the motor. Accuracy. In view of the above scientific problems, the current method based on the design of the unit motor in the arc motor, changing the structure of the tooth gap and adding the auxiliary structure are solved. There are still many scientific problems in the use of arc motors for large-caliber astronomical telescopes, such as further improvement of motor torque density and further reduction of torque ripple.

Summary of the invention

Technical Problem: In order to overcome the defects of the above-mentioned arc motor, the present invention proposes a cylindrical arc permanent magnet motor for a large-diameter astronomical telescope, which improves the torque density of the motor, weakens the positioning torque and torque fluctuation, and realizes the arc. Smoothness, reliability and accuracy of line motor operation.

Technical Solution: In order to achieve the above object, a cylindrical arc permanent magnet motor for a large-diameter telescope includes a rotor portion and a stator portion, and a rotor portion is sleeved outside the stator portion; wherein the rotor portion is composed of three circles a cylindrical rotor module, each cylindrical rotor module is composed of a cylindrical rotor core and a circular armature winding, and the annular armature winding is located in a groove of the inner circumference of the cylindrical rotor core, wherein the cylinder The rotor core comprises a rotor back yoke, a rotor tooth, a rotor slot, the rotor tooth and the rotor slot are located in the inner bore wall of the rotor back yoke; the stator portion is composed of a stator core and an array of staggered polar permanent magnets attached to the outside of the stator core.

among them,

The stator core is an arc segment having a central angle of 180° in the circumferential direction.

The staggered polarity permanent magnet array has permanent magnets as annular permanent magnets, which are evenly arranged in the circumferential direction on the stator core, adjacent annular permanent magnets have opposite polarities, and two adjacent permanent magnets of opposite polarities form a On the opposite pole, 45 pairs of poles are formed on the arc of the central angle of 180°.

The material of the staggered polarity permanent magnet ring array is made of neodymium iron boron permanent magnet or rare earth cobalt permanent magnet.

The three cylindrical rotor modules, wherein the adjacent two rotor modules are circumferentially separated by a central angle of θ=8°; the three cylindrical rotor modules and the stator form three unit motors of 12 slots and 10 poles. .

The cylindrical rotor module has a groove uniformly formed in the circumferential direction to form thirteen rotor teeth and twelve rotor slots distributed at equal intervals; the rotor slots are internally embedded with annular armature windings.

The rotor teeth, the rotor back yoke and the stator core material are all high magnetic materials.

The high magnetic permeability material is an electrical pure iron or silicon steel sheet.

The annular armature winding adopts a centralized distribution manner; the armature windings of the three cylindrical rotor modules adopt a cross-connection manner; the winding connection manner of each cylindrical rotor module adopts a double three-phase winding Connection method.

Beneficial effect: The design of the cylindrical arc permanent magnet motor can satisfy the free rotation of the pitch axis of the telescope in the range of 180°; the motor is designed as a cylindrical structure, which can realize 360° full wrapping of the ring-shaped permanent magnet and improve Compared with the conventional motor, the cylindrical arc permanent magnet motor of the invention has no winding end, increases the air gap area, and has the advantages of high torque density and small torque ripple; The armature windings of the three cylindrical rotor modules of the motor adopt centralized winding and cross-connection, which can effectively suppress spatial harmonics and torque fluctuation caused by three-phase asymmetry problem; The redundant operation and tracking accuracy of the motor, the armature winding of the cylindrical rotor module can be connected by double three-phase winding.

DRAWINGS

1 is a schematic view showing the structure of a cylindrical arc permanent magnet motor for a large-diameter telescope;

Among them are: rotor part I, stator part II;

2 is a schematic cross-sectional view of a cylindrical arc permanent magnet motor; wherein: a rotor back yoke 1, a rotor tooth 2, a rotor slot 3, an annular armature winding 4, a stator core 5, and a permanent magnet ring of staggered magnetic poles. 6;

3 is a schematic view of the components of the rotor module; wherein a is a structural diagram of the rotor back yoke 1, the rotor teeth 2, the rotor slot 3, and b is a schematic structural view of the annular armature winding 4;

4 is a schematic structural view of a stator portion; wherein a is a schematic structural view of the stator core 5, and b is a schematic structural view of a permanent magnet ring 6 with staggered magnetic poles;

Figure 5 is a schematic view of the winding connection.

Among them are: armature windings A1, B1, C1, A2, B2, C2, A3, B3, C3, the central angle θ of the adjacent two rotor modules in the circumferential direction.

Detailed ways

The present invention will be further described below with reference to the accompanying drawings.

The cylindrical arc permanent magnet motor for a large-caliber astronomical telescope according to the present invention can not only realize the free rotation of the pitch axis of the astronomical telescope in the range of 180°, and can satisfy the positioning and tracking precision of the celestial body observation, and the motor has high Torque density and torque ripple are small.

Referring to Figures 1 - 4, the present invention provides a cylindrical arc permanent magnet motor for a large-diameter astronomical telescope comprising a rotor portion I and a stator portion II.

The rotor part I is composed of three rotor modules, the rotor module adopts a cylindrical structure, and the adjacent two rotor modules are separated by a central angle of θ=8°; the three rotor modules are respectively composed of a rotor core and an annular armature winding 4 Composition.

The stator portion II is composed of a stator core 5 and a permanent magnet ring array 6 of staggered magnetic poles.

The stator core 5 is an arc segment with a central angle of 180° in the circumferential direction, and the permanent magnet array adopts a permanent magnet ring array 6 structure, and the annular permanent magnets are evenly arranged in the circumferential direction on the stator core, and the adjacent permanent magnets have opposite polarities and adjacent The two permanent magnets of opposite polarities form a pair of poles, forming 45 poles on a 180° circumference.

The 45-pole staggered magnetic pole permanent magnet ring array 6 is made of neodymium iron boron permanent magnet or rare earth cobalt permanent magnet.

The three cylindrical rotor modules and the stator together form three 10-pole 12-slot unit motors; the slots in the cylindrical rotor module are uniformly grooved in the circumferential direction to form the rotor back yoke 1 and the equidistant distribution of thirteen The rotor teeth 2 and the twelve rotor slots 3 are embedded with an annular armature winding 4 in each of the rotor slots.

The materials of the rotor back yoke 1, the rotor teeth 2, and the stator core 5 are all high magnetic materials. Such as: rotor back yoke 1, rotor teeth 2, fixed word core 5 material using electrical pure iron or silicon steel sheet.

In the cylindrical arc permanent magnet motor for a large-caliber astronomical telescope, in order to effectively suppress spatial harmonics and torque fluctuation caused by the three-phase asymmetry problem, the winding connection mode of the motor is characterized by: three circles The armature windings of the barrel rotor module are all concentrated winding, and the windings of the three cylindrical rotor modules are cross-connected. The phase sequence is: the phase sequence of the first rotor module is A1-B1-C1. The phase sequence of the second rotor module is B2-C2-A2, and the phase sequence of the third rotor module is C3-A3-B3. The three-phase windings of the three modules can form a complete three-phase symmetrical connection (A1-B2-C3 , B1-C2-A3, C1-A2-B3); At the same time, in order to achieve redundant operation and precise control of the motor, the armature windings of the three rotor modules can be connected by double three-phase windings. In combination with the winding connection method described above, the winding connection mode of the motor is as shown in FIG.

Claims

A cylindrical arc permanent magnet motor for a large-diameter telescope, characterized in that: the cylindrical arc permanent magnet motor comprises a rotor portion (I) and a stator (II) portion, and the rotor portion (I) is sleeved on the stator The outer portion of part (II); wherein the rotor portion (I) is composed of three cylindrical rotor modules, each of which is composed of a cylindrical rotor core and an annular armature winding (4), the ring The armature winding (4) is located in a groove of the inner circumference of the cylindrical rotor core, wherein the cylindrical rotor core comprises a rotor back yoke (1), a rotor tooth (2), a rotor groove (3), and a rotor tooth (2) And the rotor slot (3) is located in the inner bore wall of the rotor back yoke (1); the stator portion (II) is composed of the stator core (5) and the staggered polar permanent magnet array (6) attached to the stator core (5) Composition.
A cylindrical arc permanent magnet motor for a large-diameter astronomical telescope according to claim 1, wherein said stator core (5) is an arc segment having a central angle of 180 in the circumferential direction.
A cylindrical arc permanent magnet motor for a large-diameter astronomical telescope according to claim 1, wherein said staggered-polar permanent magnet array (6) has a permanent magnet of a ring-shaped permanent magnet at a stator core. (5) The upper side is evenly arranged in the circumferential direction, the adjacent annular permanent magnets have opposite polarities, and the adjacent two permanent magnets of opposite polarities form a pair of poles, so that 45 pairs of poles are formed on the arc of the central angle of 180°.
A cylindrical arc permanent magnet motor for a large-diameter astronomical telescope according to claim 1, wherein said alternating polarity permanent magnet ring array (6) is made of neodymium iron boron permanent magnet or rare earth cobalt. Permanent magnets.
A cylindrical arc permanent magnet motor for a large-diameter astronomical telescope according to claim 1, wherein said three cylindrical rotor modules, wherein adjacent rotor modules are circumferentially spaced apart by θ = A central angle of 8°; three cylindrical rotor modules and stators form three unit motors of 12 slots and 10 poles.
A cylindrical arc permanent magnet motor for a large-diameter astronomical telescope according to claim 1 or 5, wherein said cylindrical rotor module is uniformly grooved in the circumferential direction to form an equal interval. Thirteen rotor teeth (2) and twelve rotor slots (3) are distributed; the rotor slots (3) are internally embedded with annular armature windings (4).
A cylindrical arc permanent magnet motor for a large-diameter astronomical telescope according to claim 1, wherein said rotor tooth (2), rotor back yoke (3) and stator core (5) are made of a material High magnetic permeability material.
A cylindrical arc permanent magnet motor for a large-diameter astronomical telescope according to claim 7, wherein said high magnetic permeability material is an electrical pure iron or silicon steel sheet.
A cylindrical arc permanent magnet motor for a large-diameter astronomical telescope according to claim 1, wherein said annular armature winding (4) adopts a centralized distribution mode; three cylinders The armature windings of the rotor module adopt a cross-connection method; the winding connection mode of each cylindrical rotor module adopts a double three-phase winding connection mode.