Non-uniform air gap permanent magnet auxiliary reluctance motor

Abstract

The utility model relates to a non-uniform air gap permanent magnet auxiliary reluctance motor, the air gap of each magnetic pole of the permanent magnet auxiliary reluctance motor is divided into a plurality of sections of air gaps, and at least one section of air gap in the plurality of sections of air gaps is a non-uniform eccentric air gap. The motor can reduce the cogging torque on the premise of not increasing the motor cost, and is simple in structure and easy to implement.

Description

Technical Field

[0001] The utility model relates to the field of permanent magnet motors, and particularly relates to a permanent magnet assisted reluctance motor with non-uniform air gap. Background Art

[0002] In the prior art, as an internal permanent magnet synchronous motor, the permanent magnet assisted reluctance motor is favored for its advantages of less permanent magnet consumption, low cost, high power density, wide speed regulation range, etc. However, the existing permanent magnet assisted reluctance motor has the disadvantage of relatively large cogging torque. The existing solutions are to adopt methods such as asymmetric rotor structure, different V-shaped inclination angles, and asymmetric pole offset to reduce the cogging torque. Although these solutions can reduce the cogging torque, they are more complex in structural design and implementation and are not conducive to popularization and application. The design of the existing permanent magnet assisted reluctance motors basically adopts a uniform air gap, with n symmetric poles installed on the rotor, and the poles are symmetrically distributed in a circumferential manner at intervals of N-S. Figure 1 The structure of a conventional permanent magnet assisted reluctance motor with a uniform air gap is shown (8-pole motor, Figure 1 taking 1 / 4 of its circumference). As Figure 1 shown, the inner and outer edges of the air gap δ of this motor are circles with the outer diameter D2 of the rotor and the inner diameter Di1 of the stator as the diameters respectively, and the two are concentric circles, so they are uniformly distributed on the circumference. Summary of the Invention

[0003] The purpose of the utility model is to provide a permanent magnet assisted reluctance motor with non-uniform air gap, which can reduce the cogging torque without increasing the cost of the motor, has a simple structure and is easy to implement.

[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is: a permanent magnet assisted reluctance motor with non-uniform air gap, characterized in that the air gap of each pole of the permanent magnet assisted reluctance motor is divided into multiple sections of air gaps, and at least one section of the multiple sections of air gaps is a non-uniform eccentric air gap.

[0005] Further, the air gap of each pole of the permanent magnet assisted reluctance motor is divided into three sections of air gaps, wherein the middle section of air gap is a uniform air gap, and the air gaps on both sides are non-uniform eccentric air gaps.

[0006] Further, the permanent magnet assisted reluctance motor includes a housing, a stator and a rotor. The stator and the rotor are arranged in the housing. Coils are wound on the stator, and a plurality of permanent magnets are installed on the rotor.

[0007] Further, the entire air gap in front of each pole of the rotor is circumferentially divided into three sections of air gaps δ1, δ2, and δ3; the first permanent magnet on the frontmost side of the rotor faces the middle air gap δ2, the middle air gap δ2 takes the magnetic pole center line as the symmetric center line, and the air gaps δ1 and δ3 on both sides are symmetrically distributed with respect to the magnetic pole center line;

[0008] The middle air gap δ2 is a uniform air gap. The inner edge of the middle air gap δ2 is an arc with the center O of the motor as the center and the outer diameter D2 of the rotor as the diameter. The outer edge of the middle air gap δ2 is an arc with the center O of the motor as the center and the inner diameter Di1 of the stator as the diameter. The inner and outer edges of the middle air gap δ2 are concentric.

[0009] The air gaps δ1 and δ3 are both non-uniform eccentric air gaps. The inner edges of the air gaps δ1 and δ3 are eccentric arcs with the center O1 as the center and the radius R1 as the radius. The center O1 is the intersection of the magnetic pole center line and an eccentric circle with the center O of the motor as the center and the diameter d. The radius R1 is the distance from the center O1 to the point A1. The point A1 is the intersection of an arc with the center O of the motor as the center and the outer diameter D2 of the rotor and the center line G1 of the two permanent magnets. The center line G1 of the two permanent magnets refers to the center line of the gap between the first permanent magnet and the second permanent magnet beside it. The outer edges of the air gaps δ1 and δ3 are arcs with the center O of the motor as the center and the inner diameter Di1 of the stator as the diameter.

[0010] The inner edges of adjacent air gaps are connected, and the outer edges of adjacent air gaps are connected.

[0011] Furthermore, the diameter d of the eccentric circle is equal to 5%-10% of the outer diameter D2 of the rotor.

[0012] Furthermore, the stator is formed by laminating multiple stator punching sheets, and the rotor is formed by laminating multiple rotor punching sheets.

[0013] Furthermore, the permanent magnet is a ferrite permanent magnet.

[0014] Furthermore, front end covers and rear end covers are respectively arranged at the front and rear ends of the machine shell.

[0015] Compared with the prior art, the utility model has the following beneficial effects: The utility model provides a non-uniform air gap permanent magnet assisted reluctance motor. By designing non-uniform eccentric air gaps on the magnetic poles of the rotor, the purpose of reducing the cogging torque is achieved without increasing the cost of the motor. It not only improves the performance of the permanent magnet assisted reluctance motor, but also has a simple structure, is easy to implement, and has strong practicability and broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a structural schematic diagram of a prior art permanent magnet assisted reluctance motor with a uniform air gap;

[0017] Figure 2 is a structural schematic diagram of the non-uniform air gap permanent magnet assisted reluctance motor according to the embodiment of the utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] The present utility model will be further described below in conjunction with the accompanying drawings and embodiments.

[0019] It should be noted that the following detailed description is exemplary and is intended to provide further illustration of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs.

[0020] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular forms are also intended to include the plural forms. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0021] The present utility model provides a non-uniform air-gap permanent magnet assisted reluctance motor. The air-gap of each pole of the permanent magnet assisted reluctance motor is divided into multiple segments of air-gap, and at least one segment of the multiple segments of air-gap is a non-uniform eccentric air-gap. That is to say, there can be one, two or more segments of non-uniform eccentric air-gap among the multiple segments of air-gap; among the multiple segments of air-gap, a uniform air-gap can be arranged in the middle, and non-uniform eccentric air-gaps can be arranged on both sides, or a non-uniform eccentric air-gap can be arranged in the middle, and uniform air-gaps can be arranged on both sides, or each segment of air-gap is a non-uniform eccentric air-gap.

[0022] As Figure 2 shown, in this embodiment, the air-gap of each pole of the permanent magnet assisted reluctance motor is divided into three segments of air-gap, namely δ1, δ2, and δ3. Among them, the middle segment of air-gap δ2 is a uniform air-gap, and the air-gaps δ1 and δ3 on both sides are non-uniform eccentric air-gaps.

[0023] As Figure 2 shown, the permanent magnet assisted reluctance motor includes a housing, a stator 1, and a rotor 2. The stator 1 and the rotor 2 are arranged in the housing. A coil (not shown in the figure) is wound around the stator 1, and a plurality of ferrite magnets 3 are installed on the rotor 2. The stator 1 is formed by laminating a plurality of stator punching sheets, and the rotor 2 is formed by laminating a plurality of rotor punching sheets. Front end covers and rear end covers are respectively arranged at the front and rear ends of the housing.

[0024] The entire air-gap in front of each pole of the rotor 2 is circumferentially divided into three segments of air-gap, namely δ1, δ2, and δ3. The first magnet on the frontmost side of the rotor 2 faces the middle air-gap δ2. The middle air-gap δ2 takes the magnetic pole center line as the symmetry center line, and the air-gaps δ1 and δ3 on both sides are symmetrically distributed with respect to the magnetic pole center line.

[0025] Among them, the middle air gap δ2 is a uniform air gap. The inner edge of the middle air gap δ2 is an arc with the center O of the motor as the center and the outer diameter D2 of the rotor as the diameter. The outer edge of the middle air gap δ2 is an arc with the center O of the motor as the center and the inner diameter Di1 of the stator as the diameter. The inner and outer edges of the middle air gap δ2 are concentric.

[0026] The air gaps δ1 and δ3 are both non-uniform eccentric air gaps. The inner edges of the air gaps δ1 and δ3 are eccentric arcs with the center O1 as the center and the radius R1 as the radius. The center O1 is the intersection of the magnetic pole center line and the eccentric circle with the center O of the motor as the center and the diameter d. Here, the eccentric circle does not mean that the position of this circle is eccentric, because the center of this eccentric circle is also at O, but rather that this eccentric circle is used to generate the center O1 that deviates from the center O. The radius R1 is the distance from the center O1 to the point A1. The point A1 is the intersection of the arc with the center O of the motor as the center and the outer diameter D2 of the rotor as the diameter and the center line G1 of the two magnetic steels. The center line G1 of the two magnetic steels refers to the center line of the gap between the first magnetic steel and the second magnetic steel on its side and rear. In this embodiment, the value range of the diameter d of the eccentric circle is 5%-10% of the outer diameter D2 of the rotor. The outer edges of the air gaps δ1 and δ3 are arcs with the center O of the motor as the center and the inner diameter Di1 of the stator as the diameter.

[0027] The inner edges of adjacent air gaps are connected, and the outer edges of adjacent air gaps are connected.

[0028] The following is combined with Figure 2 , taking the N pole (the pole between the two magnetic pole center lines C1 and C2) as an example for further illustration as follows (the S pole is similar).

[0029] 1. Figure 2 The entire air gap opposite the N pole in

[0030] is divided into three air gaps, namely δ1, δ2, and δ3. Among them, the air gap δ2 takes the N pole center line Cn as the symmetric center line, and the air gaps δ1 and δ3 are symmetrically distributed with respect to the N pole center line Cn. Figure 2 The middle air gap δ2 opposite the first magnetic steel N1 of the N pole is a uniform air gap. The inner edge of the middle air gap δ2 is an arc with the center O of the motor as the center and the outer diameter D2 of the rotor (the radius corresponding to the outer diameter D2 of the rotor is the rotor radius R in

[0031] 3. The air gaps δ1 and δ3 are both non-uniform eccentric air gaps. The inner edges of the air gaps δ1 and δ3 are eccentric arcs with the center O1 as the center and the radius R1. The center O1 is the intersection of the N-pole center line Cn and the eccentric circle with the motor center O as the center and the diameter d. The radius R1 is the distance from the center O1 to the point A1. The point A1 is the intersection of the arc with the motor center O as the center and the rotor outer diameter D2 as the diameter and the center line G1 of the two magnets. The center line G1 of the two magnets refers to the center line of the gap between the first magnet N1 and the second magnet on its side and rear. From Figure 2 It can be seen that a second magnet is provided on the side and rear of the first magnet N1. The second magnet is of a U-shaped structure and is composed of magnets N2 and N4 on the left and right sides of the magnet N1 and the magnet N3 on the rear side of the magnet N1. The gap between the first magnet N1 and the magnet N2 (N4) on its side is divided into two equal parts along the width direction by a center line, and this center line is the center line G1 of the two magnets.

[0032] The outer edges of the air gaps δ1 and δ3 are arcs with the motor center O as the center and the stator inner diameter Di1 as the diameter.

[0033] 4. The inner edges of adjacent air gaps are connected, and the outer edges of adjacent air gaps are connected.

[0034] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention in other forms. Any person skilled in the art may use the technical content disclosed above to make changes or modifications into equivalent embodiments with equivalent changes. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the technical solution content of the present invention still fall within the protection scope of the technical solution of the present invention.

Claims

1. A non-uniform air-gap permanent magnet assisted reluctance motor, characterized in that The air gap of each pole of the permanent magnet assisted reluctance motor is divided into three sections of air gaps, where the middle section of the air gap is a uniform air gap, and the air gaps on both sides are non-uniform eccentric air gaps; the permanent magnet assisted reluctance motor includes a housing, a stator and a rotor, the stator and the rotor are arranged in the housing, coils are wound on the stator, and a number of permanent magnets are installed on the rotor; The entire air gap in front of each pole of the rotor is circumferentially divided into three sections of air gaps δ1, δ2, and δ3; the first permanent magnet on the frontmost side of the rotor faces the middle air gap δ2, the middle air gap δ2 takes the pole center line as the symmetric center line, and the air gaps δ1 and δ3 on both sides are symmetrically distributed with respect to the pole center line; The middle air gap δ2 is a uniform air gap, the inner edge of the middle air gap δ2 is an arc with the center of the motor O as the center and the rotor outer diameter D2 as the diameter, the outer edge of the middle air gap δ2 is an arc with the center of the motor O as the center and the stator inner diameter Di1 as the diameter, and the inner and outer edges of the middle air gap δ2 are concentric; The air gaps δ1 and δ3 are both non-uniform eccentric air gaps, the inner edges of the air gaps δ1 and δ3 are eccentric arcs with the center O1 as the center and the radius R1 as the radius, the center O1 is the intersection of the pole center line and the eccentric circle with the center of the motor O as the center and the diameter d, the radius R1 is the distance from the center O1 to the point A1, and the point A1 is the intersection of the arc with the center of the motor O as the center and the rotor outer diameter D2 as the diameter and the center line G1 of the two permanent magnets; the center line G1 of the two permanent magnets refers to the center line of the gap between the first permanent magnet and the second permanent magnet adjacent to it; the outer edges of the air gaps δ1 and δ3 are arcs with the center of the motor O as the center and the stator inner diameter Di1 as the diameter; The inner edges of adjacent air gaps are connected, and the outer edges of adjacent air gaps are connected.

2. The non-uniform air-gap permanent magnet assisted reluctance motor according to claim 1, characterized in that The diameter d of the eccentric circle is equal to 5%-10% of the rotor outer diameter D2.

3. A non-uniform air-gap permanent magnet assisted reluctance motor according to claim 1, characterized in that, The stator is formed by stacking a plurality of stator punching sheets, and the rotor is formed by stacking a plurality of rotor punching sheets.

4. A non-uniform air-gap permanent magnet assisted reluctance motor according to claim 1, characterized in that, The permanent magnet is a ferrite permanent magnet.

5. A non-uniform air-gap permanent magnet assisted reluctance motor according to claim 1, characterized in that, Front end covers and rear end covers are respectively arranged at the front and rear ends of the housing.

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