A skew pole rotor structure for a permanent magnet motor

Abstract

This invention discloses a skewed rotor structure for a permanent magnet motor, comprising two pole plates mounted on a rotor support and multiple permanent magnet poles arranged in N segments along the axial direction between the pole plates. Each permanent magnet pole consists of a permanent magnet and a pole core, which is made of N types of laminations stacked together. The permanent magnet pole segments are staggered circumferentially. By installing the pole cores sequentially in a specified order in both forward and reverse directions, segmented skewed rotor configuration can be achieved. This invention solves the problem of complex skewed pole manufacturing processes and reduces the number of lamination dies, resulting in significant economic benefits and wide applicability in the field of permanent magnet motors.

Description

Technical Field

[0001] This invention belongs to the field of permanent magnet motor technology, and specifically relates to a skewed rotor structure for a permanent magnet motor. Background Technology

[0002] Cogging torque is a problem unique to permanent magnet motors. It refers to the torque generated by the interaction between the permanent magnet and the stator core when the stator windings are not energized. This torque causes vibration and noise in the motor and results in torque fluctuations, affecting the motor's performance.

[0003] Currently, the common method to reduce cogging torque in permanent magnet motors is to use a segmented skewed pole design, which involves placing the permanent magnets at a certain angle along the circumference. This requires that the mounting slots or fixing holes of the permanent magnet poles also be staggered and processed in segments during production, which makes the motor manufacturing process complicated and increases costs. Summary of the Invention

[0004] The purpose of this invention is to provide a skewed rotor structure for a permanent magnet motor, so as to achieve segmented skewed poles while reducing processing difficulty and manufacturing cost.

[0005] The technical solution adopted by this invention to solve its technical problem is: a skewed rotor structure for a permanent magnet motor, including two magnetic pole baffles mounted on a rotor support and multiple permanent magnet poles arranged in N segments along the axial direction between the magnetic pole baffles; the permanent magnet poles are composed of multiple permanent magnet segments and magnetic pole cores, and the magnetic pole cores are made by stacking N types of laminations, the type of laminations being determined by the number N segments along the axial direction of the magnetic pole; each segment of permanent magnet poles is offset by a certain angle α along the circumference. If N is an even number, the number of lamination dies is N / 2, and each lamination is offset from the center line by α, 2α, 3α...Nα / 2 in sequence, and is numbered 1, 2, 3...N / 2 in sequence; if N is an odd number, the number of lamination dies is (N+1) / 2, and each lamination is offset from the center line by α, 2α, 3α...(N+1)α / 2 in sequence, and is numbered 1, 2, 3...(N+1) / 2 in sequence.

[0006] Furthermore, during installation, the permanent magnet poles are first installed axially in the order of the numbers mentioned above, and then installed in reverse order to ensure that each segment of permanent magnet poles is staggered by the same angle along the circumference, thus achieving segmented oblique poles.

[0007] The skewed rotor structure of the permanent magnet motor has a pole clamping block installed between the permanent magnet poles, and a pole tie rod provided at the bottom of the permanent magnet. The pole clamping block and the pole tie rod are respectively connected and fixed to the rotor bracket by bolts.

[0008] The skewed rotor structure of the permanent magnet motor has a straight groove on the rotor support for mounting the permanent magnet poles.

[0009] The slanted-pole rotor structure of the permanent magnet motor has threaded holes for bolt installation on the magnetic pole tie rods that are distributed in a straight line along the axial direction.

[0010] The beneficial effects of this invention are: compared with the existing skewed pole rotor, the skewed pole rotor structure of this invention can reduce the number of lamination dies, and only straight slots need to be machined on the rotor, which can reduce the processing cost caused by the skewed pole, and has better economic benefits while ensuring motor performance. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of the present invention;

[0012] Figure 2 for Figure 1 Sectional view along the middle AA direction;

[0013] Figure 3 for Figure 2 A magnified view of part B in the middle section;

[0014] Figure 4 This is a schematic diagram of the permanent magnet pole structure of the present invention;

[0015] Figures 5-7 These are schematic diagrams of three types of laminations in the invention examples.

[0016] The labels in the attached figures are as follows: 1—magnetic pole baffle, 2—permanent magnet pole, 2.1—permanent magnet, 2.2—magnetic pole core, 3—magnetic pole pressing block, 4—magnetic pole pull rod. Detailed Implementation

[0017] The specific embodiments of the present invention will now be described in conjunction with the accompanying drawings and examples to enable those skilled in the art to better understand the present invention. Example 1

[0018] Reference Figure 1 , Figure 2 and Figure 3As shown, the present invention discloses a skewed rotor structure for a permanent magnet motor, comprising two pole plates 1 mounted on a rotor support and multiple permanent magnet poles 2 arranged in N segments along the axial direction between the pole plates 1; each permanent magnet pole 2 is composed of multiple permanent magnet segments 2.1 and a pole core 2.2, the pole core 2.2 being made of N types of laminations, the lamination type being determined by the number of axial segments N; each permanent magnet pole segment 2 is offset circumferentially by a certain angle α, the aforementioned number of axial segments N and... The offset angle α of each permanent magnet pole 2 segment is usually determined by the designer based on the motor pole slot fit. If N is an even number, the number of lamination dies is N / 2, and each lamination is offset from the center line by α, 2α, 3α…Nα / 2, and numbered 1, 2, 3…N / 2. If N is an odd number, the number of lamination dies is (N+1) / 2, and each lamination is offset from the center line by α, 2α, 3α…(N+1)α / 2, and numbered 1, 2, 3…(N+1) / 2. During installation, the permanent magnet poles 2 are first installed axially in the above numbering order, and then installed in reverse order to ensure that each segment of the permanent magnet pole 2 is offset by the same angle along the circumference, thus achieving segmented oblique poles.

[0019] Furthermore, a pole clamping block 3 is installed between the poles of the permanent magnet pole 2, and a pole tie rod 4 is provided at the bottom of the permanent magnet 2.1. The pole clamping block 3 and the pole tie rod 4 are respectively connected and fixed to the rotor support by bolts. The mounting groove for mounting the permanent magnet pole 2 on the rotor support is a straight groove. The threaded holes for bolt mounting on the pole tie rod 4 are distributed in a straight line along the axial direction. Example 2

[0020] This embodiment is based on a skewed pole structure with 18 poles, 216 slots, and 5 axial segments for the permanent magnet poles. Therefore, each pole segment is offset 0.333° circumferentially, and the total skew angle is 1.667°. Figure 5 As shown, the permanent magnet poles 2 are numbered sequentially as 2.2-1, 2.2-2, 2.2-3, 2.2-4, and 2.2-5.

[0021] In actual manufacturing, only three types of laminations need to be processed, such as... Figures 5-7 As shown, when installing permanent magnet pole 2, install 2.2-1, 2.2-2, and 2.2-3 in sequence, and then install 2.2-2 and 2.2-1 in reverse order, thus forming a slanted pole structure with 5 axial segments, each segment offset by 0.333°.

[0022] Compared to the background technology, the magnetic pole structure provided by this invention solves the problems of complex manufacturing process and high processing cost of the current permanent magnet motor skew poles, and can be widely used in the field of permanent magnet motors.

[0023] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A skewed-pole rotor structure for a permanent magnet motor, comprising two pole plates (1) mounted on a rotor support and a plurality of permanent magnet poles (2) arranged in N segments along the axial direction between the pole plates (1); characterized in that: The permanent magnet pole (2) is composed of a permanent magnet (2.1) and a pole core (2.2). The pole core (2.2) is made of multiple laminations stacked together. When installing the permanent magnet pole (2), it is first installed in axial order according to the numbering, and then installed in reverse order according to the numbering. Each permanent magnet pole (2) is offset by an angle α along the circumference. If N is even, each lamination is offset from the center line by α, 2α, 3α...Nα / 2, and is numbered 1, 2, 3...N / 2. If N is odd, each lamination is offset from the center line by α, 2α, 3α...(N+1)α / 2, and is numbered 1, 2, 3...(N+1) / 2.

2. The skewed rotor structure of a permanent magnet motor according to claim 1, characterized in that, The permanent magnet poles (2) are equipped with pole blocks (3) between their poles, and the permanent magnet (2.1) is provided with pole rods (4) at its bottom. The pole blocks (3) and pole rods (4) are respectively connected to the rotor support by bolts.

3. The skewed rotor structure of a permanent magnet motor according to claim 2, characterized in that, The rotor support is provided with a straight slot for mounting permanent magnet poles (2).

4. The skewed rotor structure of a permanent magnet motor according to claim 2, characterized in that, The magnetic pole tie rod (4) has threaded holes for mounting bolts distributed in a straight line along the axial direction.

Images