CN-121984298-A - High-torque-density permanent magnet synchronous motor for unmanned aerial vehicle

CN121984298ACN 121984298 ACN121984298 ACN 121984298ACN-121984298-A

Abstract

The invention provides a high-torque-density permanent magnet synchronous motor for an unmanned aerial vehicle, and belongs to the technical field of high-torque-density radial magnetic flux stator-yoke-free double-rotor permanent magnet synchronous motors. The invention comprises an outer rotor, a stator, an inner rotor and a rotating shaft; the inner rotor yoke in the inner rotor is uniformly distributed with segment permanent magnet slot units along the circumferential direction, the segment permanent magnet slot units are of radial symmetrical structures, the N poles of the rotor are adjacent to the S poles of the rotor and are respectively embedded into the segment permanent magnet slot units, the outer rotor permanent magnet in the outer rotor is fixedly arranged on the inner side of the outer rotor yoke, the stator comprises a stator iron core module and stator coils, the stator iron core module is uniformly distributed between the outer rotor and the inner rotor along the circumferential direction, and the stator coils are wound on the stator iron core module. The invention can effectively improve the torque density, lighten the weight of the rotor, reduce the torque pulsation, improve the thrust-weight ratio of the unmanned aerial vehicle power system and maximize the output torque by the dislocation angle of the inner rotor and the outer rotor.

Inventors

ZHAO XIAOKUN
WU YAO
GUAN ZHENYU
WANG WEINAN
WEI JIAN

Assignees

东北林业大学

Dates

Publication Date: 20260505
Application Date: 20251227

Claims (9)

1. The high-torque-density permanent magnet synchronous motor for the unmanned aerial vehicle comprises an outer rotor (1), a stator (2), an inner rotor (3) and a rotating shaft (6), wherein the outer rotor (1) is sleeved outside the stator (2) and an outer air gap (4) is arranged between the outer rotor and the stator, the inner rotor (3) is sleeved inside the stator (2) and an inner air gap (5) is arranged between the inner rotor and the stator, the inner rotor (3) is fixedly sleeved outside the rotating shaft (6), The inner rotor (3) comprises a plurality of rotor N poles, a plurality of rotor S poles and an inner rotor yoke (15), wherein a plurality of segment permanent magnet groove units (16) are uniformly distributed in the inner rotor yoke (15) along the circumferential direction, the plurality of segment permanent magnet groove units (16) are of radial symmetrical structures, and each rotor N pole is adjacent to each rotor S pole and is respectively embedded into the plurality of segment permanent magnet groove units (16); the outer rotor (1) comprises an outer rotor permanent magnet and an outer rotor yoke (9), wherein the outer rotor permanent magnet is fixedly arranged on the inner side of the outer rotor yoke (9); The stator (2) comprises a plurality of stator core modules (12) and stator coils (13), wherein the plurality of stator core modules (12) are uniformly distributed between the outer rotor (1) and the inner rotor (3) along the circumferential direction, and the stator coils (13) are wound on the stator core modules (12).
2. A high torque density permanent magnet synchronous motor for an unmanned aerial vehicle according to claim 1, wherein each of the segment permanent magnet slot units (16) comprises a plurality of permanent magnet slots arranged in segments, the plurality of permanent magnet slots being arranged in a V-shape, U-shape or W-shape.
3. The high-torque-density permanent magnet synchronous motor for the unmanned aerial vehicle according to claim 2, wherein each rotor N pole and each rotor S pole comprise a plurality of inner rotor permanent magnets (7) with the same number, and the plurality of inner rotor permanent magnets (7) are respectively embedded into the plurality of permanent magnet grooves.
4. A high torque density permanent magnet synchronous motor for an unmanned aerial vehicle according to claim 2, wherein a magnetic bridge (8) is provided between two adjacent permanent magnet slots in each segment permanent magnet slot unit (16).
5. The high torque density permanent magnet synchronous motor for an unmanned aerial vehicle of claim 2, wherein the number of rotor N poles and rotor S poles is Each rotor N pole and each rotor S pole have the angle of the corresponding circle center , Is the pole pair number of the motor.
6. The high torque density permanent magnet synchronous motor for an unmanned aerial vehicle according to claim 5, wherein each segment permanent magnet slot unit (16) is arranged in a V-shape, each rotor N-pole and each rotor S-pole are respectively formed by The total number of the inner rotor permanent magnets (7) of the rotor N pole and the rotor S pole is respectively The total number of the inner rotor permanent magnets (7) is The number of the two-dimensional space-saving type, Is the number of single-sided magnetic bridges (8) of the segment permanent magnet slot units (16), wherein 。
7. The high-torque-density permanent magnet synchronous motor for the unmanned aerial vehicle according to claim 1, wherein the outer rotor permanent magnet comprises a plurality of main permanent magnets (10) and a plurality of auxiliary permanent magnets (11), and the main permanent magnets (10) and the auxiliary permanent magnets (11) are alternately arranged to form a Halbach annular array.
8. A high torque density permanent magnet synchronous motor for an unmanned aerial vehicle according to claim 7, wherein the magnetization direction of each of the main permanent magnets (10) is radial magnetization and the magnetization direction of each of the auxiliary permanent magnets (11) is tangential magnetization.
9. The high torque density permanent magnet synchronous motor for unmanned aerial vehicle according to claim 1, wherein the mechanical angle corresponding to the time when the inner rotor (3) alone generates the maximum electromagnetic torque is The mechanical angle corresponding to the condition that the outer rotor (1) singly generates the maximum electromagnetic torque is The magnetic field axes of the inner rotor (3) and the outer rotor (1) are staggered Mechanical angle.

Description

High-torque-density permanent magnet synchronous motor for unmanned aerial vehicle Technical Field The invention relates to a high-torque-density permanent magnet synchronous motor for an unmanned aerial vehicle, and belongs to the technical field of high-torque-density radial magnetic flux stator-yoke-free double-rotor permanent magnet synchronous motors. Background The motor is used as a core driving component of the unmanned aerial vehicle, and the performance of the motor directly determines the thrust-weight ratio and the endurance capacity of the whole unmanned aerial vehicle, so that the unmanned aerial vehicle motor is required to have high torque density characteristics. In order to meet the requirements of high torque output and light weight, the existing unmanned aerial vehicle adopts an external rotor surface-mounted permanent magnet synchronous motor structure. The motor can obtain higher output torque under the same magnetic density condition by increasing the action radius of the air gap magnetic field, thereby realizing higher torque density. However, the traditional external rotor surface-mounted permanent magnet synchronous motor has the problem of low space utilization rate in structural design. Meanwhile, in order to ensure that the iron core on the main magnetic flux path is unsaturated, the stator yoke is usually required to be kept at a certain thickness, which not only increases the motor quality, but also occupies the winding space, and limits the further improvement of the electromagnetic torque. Therefore, a high-torque-density permanent magnet synchronous motor for an unmanned aerial vehicle needs to be provided, and the problems of low space utilization rate, low torque density and low power performance of the traditional external-rotor surface-mounted permanent magnet synchronous motor are solved. Disclosure of Invention The invention aims to solve the problems in the prior art, and further provides a high-torque-density permanent magnet synchronous motor for an unmanned aerial vehicle, which is characterized in that an effective magnetic field space is fully utilized by adopting a rotor design, a stator yoke part is omitted to reduce the volume of an ineffective iron core, and the winding arrangement space is enlarged, so that the torque density and the power performance of the motor are improved, and the requirements of the unmanned aerial vehicle on an efficient and lightweight driving system are met. The invention aims at realizing the following technical scheme: The high-torque-density permanent magnet synchronous motor for the unmanned aerial vehicle comprises an outer rotor, a stator, an inner rotor and a rotating shaft, wherein the outer rotor is sleeved outside the stator, an outer air gap is arranged between the outer rotor and the stator, the inner rotor is sleeved inside the stator, an inner air gap is arranged between the inner rotor and the stator, and the inner rotor is fixedly sleeved outside the rotating shaft; the inner rotor comprises a plurality of rotor N poles, a plurality of rotor S poles and an inner rotor yoke, wherein a plurality of segment permanent magnet groove units are uniformly distributed in the inner rotor yoke along the circumferential direction, the segment permanent magnet groove units are of radial symmetrical structures, and each rotor N pole is adjacent to each rotor S pole and is respectively embedded into the segment permanent magnet groove units; the outer rotor comprises an outer rotor permanent magnet and an outer rotor yoke, wherein the outer rotor permanent magnet is fixedly arranged on the inner side of the outer rotor yoke; the stator comprises a plurality of stator core modules and stator coils, wherein the stator core modules are uniformly distributed between the outer rotor and the inner rotor along the circumferential direction, and the stator coils are wound on the stator core modules. Preferably, each segment permanent magnet slot unit comprises a plurality of permanent magnet slots which are arranged in a segment mode, and the plurality of permanent magnet slots are arranged in a V-shaped, U-shaped or W-shaped mode. Preferably, each rotor N pole and each rotor S pole include a plurality of inner rotor permanent magnets with the same number, and the plurality of inner rotor permanent magnets are respectively embedded in the plurality of permanent magnet slots. Preferably, a magnetic bridge is arranged between two adjacent permanent magnet slots in each segment permanent magnet slot unit. Preferably, the number of N poles and S poles of the rotor isEach rotor N pole and each rotor S pole have the angle of the corresponding circle center,Is the pole pair number of the motor. Preferably, each segment permanent magnet slot unit is arranged in a V shape, and each rotor N pole and each rotor S pole are respectively formed byThe total number of the inner rotor permanent magnets of the rotor N pole and the rotor S pole is respectiv