Armature enhanced modular stator vernier permanent magnet electric machine

Abstract

The application discloses an armature enhanced modular stator vernier permanent magnet motor, belongs to the motor field, and applies a stator magnetic barrier to the vernier permanent magnet motor as a modulation unit of an armature winding, breaks the original understanding of the magnetic barrier through a physical concept, and the stator magnetic barrier can enhance the cross-linking capacity of the armature winding to an excitation magnetic field, simultaneously enhances the magnetic motive force of multiple working armatures of the vernier permanent magnet motor, and thus increases the torque density of the motor; and a split tooth structure is adopted for the first stator tooth, the end length of the winding is shortened, and the motor volume is reduced; in addition, the magnetic barrier shape with the air gap side width being greater than the non-air gap side width can increase the first stator slot area without influencing the air gap structure, more windings are placed, and the torque density of the motor is further improved.

Description

Technical Field

[0001] This invention belongs to the field of electric motors, and more specifically, relates to an armature-enhanced modular stator vernier permanent magnet motor. Background Technology

[0002] Vernier permanent magnet motors (PMMs) have garnered significant attention in academia due to their inherent high torque density, low torque ripple, and high sinusoidal no-load back EMF, and possess broad prospects for industrial applications. Compared to traditional permanent magnet motors, PMMs can generate multiple operating harmonics through magnetic field modulation, which work together to produce average torque. However, current utilization of these operating harmonics in the armature windings of PMMs is not yet fully realized, and there is still room for improvement in torque output capability.

[0003] Stator magnetic barriers are typically used to reduce lower-order magnetic flux density harmonics and improve motor efficiency. However, they also reduce the motor's operating magnetic flux density harmonics, resulting in a sacrifice in torque density, which refers to the torque produced per unit volume of the motor. From a physical perspective, stator magnetic barriers are generally considered to interrupt the path of lower-order magnetic flux, forcing the magnetic lines of force to pass through the air gap multiple times, increasing magnetic reluctance, and thus suppressing lower-order magnetic flux. Summary of the Invention

[0004] In view of the above-mentioned defects or improvement needs of the prior art, the present invention provides an armature-enhanced modular stator vernier permanent magnet motor, which can improve the linkage capability of the armature winding with the excitation magnetic field and increase the torque density of the vernier permanent magnet motor without increasing the electrical load.

[0005] To achieve the above objectives, the present invention provides an armature-enhanced modular stator vernier permanent magnet motor, comprising: a stator assembly and a rotor assembly coaxially mounted, wherein an air gap exists between the stator assembly and the rotor assembly;

[0006] The stator assembly includes a stator core and an armature winding; the stator core includes multiple stator modules arranged in a ring, with gaps between each stator module to form a stator magnetic barrier; when each stator magnetic barrier is completely filled, the stator core is cylindrical in shape.

[0007] The stator module includes a stator yoke, a first stator tooth, and a second stator tooth; the first stator tooth and the second stator tooth are respectively disposed in the middle and at both ends of the stator yoke, and a first stator slot is provided between the first stator tooth and the second stator tooth for placing the armature winding; the first stator tooth includes a main tooth and two split teeth, and a second stator slot is provided between the two split teeth; the width of the stator magnetic barrier near the stator yoke side is smaller than the width near the air gap side;

[0008] The second stator tooth is used to wind the coil of the armature winding. The two ends of the coil are respectively wound on the adjacent second stator teeth of the adjacent stator module, and the central axis of the coil after winding coincides with the central axis of the stator magnetic barrier between the adjacent stator modules. The number of stator modules and the number of armature winding coils are both N, where N is a multiple of the number of winding phases.

[0009] The rotor assembly includes a rotor core and permanent magnets. The rotor core is annular, and the permanent magnets are distributed in a ring on the air gap side of the rotor core.

[0010] In summary, compared with the prior art, the above-described technical solutions conceived by this invention can achieve the following beneficial effects:

[0011] The armature-enhanced modular stator vernier permanent magnet motor provided by this invention applies stator magnetic barriers to the vernier permanent magnet motor, using the stator magnetic barriers as modulation units of the armature windings. This breaks away from the original understanding of magnetic barriers based on physical concepts. The stator magnetic barriers can enhance the linkage capability of the armature windings to the excitation magnetic field, and at the same time enhance the magnetomotive force of multiple working armatures of the vernier permanent magnet motor, thereby increasing the torque density of the motor. Furthermore, the first stator tooth adopts a split tooth structure, which shortens the end length of the winding and reduces the size of the motor. In addition, the magnetic barrier shape with a width on the air gap side greater than that on the non-air gap side can increase the area of ​​the first stator slot without affecting the air gap structure, thereby accommodating more windings and further improving the torque density of the motor.

[0012] As a further preferred embodiment, the armature-enhanced modular stator vernier permanent magnet motor provided by this invention has different widths in the first stator slot, the second stator slot, and the stator magnetic barrier air gap side, forming a non-uniformly distributed air gap structure, generating multiple air gap magnetic permeability harmonics. The rotor excitation magnetic field is modulated by the magnetic field of the non-uniform air gap, generating multiple working harmonics that link with the armature windings and work together to produce an average torque, thereby further improving the torque density of the motor.

[0013] As a further preferred embodiment, the armature-enhanced modular stator vernier permanent magnet motor provided by the present invention adopts a semi-open slot structure for the first stator slot. Compared with the straight-tooth open slot structure adopted by the stator slot of the conventional vernier permanent magnet motor, the slot opening is smaller, which can increase the slot coefficient of the armature winding, further enhance the ability of the armature winding to link the excitation magnetic field, and improve the torque density of the motor.

[0014] As a further preferred embodiment, the armature-enhanced modular stator vernier permanent magnet motor provided by the present invention has a first stator slot with a width closer to the stator yoke than a width closer to the air gap, which can increase the area of ​​the first stator slot, thereby accommodating more windings and further improving the torque density of the motor.

[0015] As a further preferred embodiment, the armature-enhanced modular stator vernier permanent magnet motor provided by the present invention has a second stator slot that is triangular arched in the cross-section of the stator module. This can minimize the space occupied while ensuring that the air gap magnetic permeability is not affected, thereby increasing the area of ​​the first stator slot, thus allowing for the placement of more windings and further improving the torque density of the motor. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the overall structure of a modular stator vernier permanent magnet motor with an enhanced armature and an external stator and internal rotor, provided in an embodiment of the present invention.

[0017] Figure 2 This is a schematic diagram of the overall structure of the modular stator vernier permanent magnet motor with enhanced external rotor and internal stator armature provided in an embodiment of the present invention.

[0018] Figure 3 This is a schematic diagram of the stator structure of an armature-enhanced modular stator vernier permanent magnet motor provided in an embodiment of the present invention.

[0019] Figure 4 This is a cross-sectional view of the stator module of the armature-enhanced modular stator vernier permanent magnet motor provided in an embodiment of the present invention.

[0020] Figure 5 This is a schematic diagram of the rotor structure of an armature-enhanced modular stator vernier permanent magnet motor provided in an embodiment of the present invention.

[0021] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0022] 1 is the stator, 2 is the rotor, 3 is the stator core, 4 is the armature winding, 5 is the stator magnetic barrier, 6 is the first stator slot, 7 is the second stator slot, 8 is the first stator tooth, 9 is the second stator tooth, 10 is the main tooth, 11 is the split tooth, 12 is the rotor core, and 13 is the rotor permanent magnet. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0024] This invention provides an armature-enhanced modular stator vernier permanent magnet motor, comprising: a stator assembly 1 and a rotor assembly 2 coaxially mounted, wherein the stator assembly 1 and the rotor assembly 2 have an air gap between them;

[0025] The stator assembly 1 includes a stator core 3 and an armature winding 4; the stator core 3 includes multiple stator modules arranged in a ring, with gaps between each stator module to form a stator magnetic barrier 5; when each stator magnetic barrier 5 is completely filled, the stator core 3 is cylindrical in shape.

[0026] The stator module includes a stator yoke, a first stator tooth 8, and a second stator tooth 9; the first stator tooth 8 and the second stator tooth 9 are respectively disposed in the middle and at both ends of the stator yoke, and a first stator slot 6 is provided between the first stator tooth 8 and the second stator tooth 9 for placing the armature winding 4; the first stator tooth 8 includes a main tooth 10 and two split teeth 11, and a second stator slot 7 is provided between the two split teeth 11; the width of the stator magnetic barrier 5 near the stator yoke side is smaller than the width near the air gap side;

[0027] The second stator tooth 9 is used to wind the coil of the armature winding 4. The two ends of the coil are respectively wound on the adjacent second stator teeth 9 of the adjacent stator modules, and the central axis of the coil after winding coincides with the central axis of the stator magnetic barrier between the adjacent stator modules; wherein, the number of stator modules and the number of coils of the armature winding 4 are both N, and N is a multiple of the number of winding phases;

[0028] The rotor assembly 2 includes a rotor core 12 and permanent magnets 13. The rotor core 12 is annular, and the permanent magnets 13 are distributed in a ring on the air gap side of the rotor core 12.

[0029] The motor provided in this embodiment of the invention can be as follows: Figure 1 The external rotor internal stator motor shown can also be as follows: Figure 2 The external stator and internal rotor motor shown.

[0030] The following description uses an external rotor internal stator motor with 3 winding phases and N=6 as an example to further illustrate the motor provided in the embodiment of the present invention.

[0031] like Figure 1 , 3 As shown, the motor provided in this embodiment of the invention includes a stator assembly 1 and a rotor assembly 2 coaxially mounted, with an air gap between the stator assembly 1 and the rotor assembly 2.

[0032] Stator assembly 1 includes stator core 3 and armature winding 4;

[0033] The stator core comprises multiple stator modules, with gaps between adjacent modules forming stator magnetic barriers 5. This divides the stator core 3 into six uniform segments, creating six modular stators, which enhance the magnetomotive force of the working armature. It is understood that the specific value of N is determined by the number of excitation pole pairs, the coil span, and the space utilization rate of the stator core, and can be selected according to actual needs.

[0034] In this example, a total of 6 stator magnetic barriers 5 are set up, and the stator core 3 is evenly cut into 6 segments to form a modular stator, which plays a role in modulating the magnetic circuit of the yoke, enhancing the linkage capability of the armature winding 4 to the excitation magnetic field, and enhancing the magnetomotive force of the working armature.

[0035] After the magnetic barrier 5 is completely filled with non-magnetic material, the stator core becomes cylindrical. A groove is formed on one side of the cylinder wall, creating a first stator slot 6 and a second stator slot 7. The first stator slot 6 houses the armature winding 4, and the second stator slot 7 modulates the magnetic field. The stator core includes a first stator tooth 8 and a second stator tooth 9. The first stator tooth 8 consists of one main tooth 10 and two split teeth 11, each with the same shape and size. The second stator tooth 9 contains only one main tooth and is used to wind the winding coil. The first and second stator teeth and the first and second stator slots on the air gap side all function as magnetic field modulators, and the second stator tooth 9 also functions as the armature winding.

[0036] The armature winding 4 is a concentrated winding with a span of 1. The winding contains N coils, each coil crossing the two adjacent second stator teeth 9 of two adjacent stator modules and the stator magnetic barrier 5 between the two stator modules, and the central axis of the winding coincides with the central axis of the stator magnetic barrier 5.

[0037] Preferably, such as Figure 3 As shown, the stator magnetic barrier 5 is narrower near the yoke (i.e., the stator yoke) and wider near the air gap. This can shorten the width of the stator magnetic barrier yoke while ensuring that the air gap magnetic field modulation effect remains unchanged, thereby increasing the stator slot area.

[0038] Preferably, the width of the first stator slot 5 and the width of the second stator slot 7 are different from the width of the air gap side of the stator magnetic barrier 5, which increases the number of magnetic conduction harmonics, thereby generating more working harmonics and improving torque density.

[0039] The interaction between the magnetic field and the air gap magnetic permeability harmonics generates multiple working magnetic flux densities. These multiple working magnetic flux densities work together to contribute torque, thereby increasing torque density.

[0040] The first stator slot 6 serves to house the armature winding 4.

[0041] Preferably, the first stator slot 6 adopts a semi-open slot structure, which not only achieves the modulation effect but also increases the slot coefficient of the motor, thereby increasing the magnetomotive force of the working armature.

[0042] Preferably, the width of the first stator slot 6 near the stator yoke side is greater than the width near the air gap side, which increases the slot area.

[0043] The second stator slot 7 does not house the armature winding; it only serves to modulate the magnetic field.

[0044] Specifically, such as Figure 4 As shown, in the cross-section of the stator module, the second stator slot 7 is triangular arched, the purpose of which is to minimize the space occupied while ensuring that the air gap magnetic permeability is not affected, thereby increasing the area of ​​the first stator slot 6.

[0045] Rotor assembly 2 includes rotor core 12 and permanent magnet 13, such as Figure 5 As shown. The rotor core 12 is annular (e.g., annular silicon steel sheet), and multiple pairs of permanent magnets 13 are evenly distributed near the air gap side (in this embodiment of the invention, 19 pairs of permanent magnets are used as an example, with a tile-shaped shape). The permanent magnets 13 are magnetized radially, with the magnetization directions alternating between inward and outward.

[0046] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An armature-enhanced modular stator vernier permanent magnet motor, characterized in that, include: A stator assembly (1) and a rotor assembly (2) are coaxially fitted together, and there is an air gap between the stator assembly (1) and the rotor assembly (2); The stator assembly (1) includes a stator core (3) and an armature winding (4); the stator core (3) includes multiple stator modules arranged in a ring, and there are gaps between each stator module to form a stator magnetic barrier (5); when each stator magnetic barrier (5) is completely filled, the stator core (3) is cylindrical in shape. The stator module includes a stator yoke, a first stator tooth (8), and a second stator tooth (9); the first stator tooth (8) and the second stator tooth (9) are respectively disposed in the middle and at both ends of the stator yoke, and a first stator slot (6) is provided between the first stator tooth (8) and the second stator tooth (9) for placing the armature winding (4); the first stator tooth (8) includes a main tooth (10) and two split teeth (11), and a second stator slot (7) is provided between the two split teeth (11); the width of the stator magnetic barrier (5) near the stator yoke is smaller than the width near the air gap. The second stator tooth (9) is used to wind the coil of the armature winding (4). The two ends of the coil are respectively wound on the adjacent second stator tooth (9) of the adjacent stator module, and the central axis of the coil after winding coincides with the central axis of the stator magnetic barrier between the adjacent stator modules; wherein, the number of stator modules and the number of coils of the armature winding (4) are both N, and N is a multiple of the number of winding phases; The rotor assembly (2) includes a rotor core (12) and a permanent magnet (13). The rotor core (12) is annular, and the permanent magnet (13) is distributed in a ring on the air gap side of the rotor core (12). The air gap widths of the first stator slot (6), the second stator slot (7), and the stator magnetic barrier (5) are all different.

2. The motor as described in claim 1, characterized in that, The first stator slot (6) is a semi-open slot structure.

3. The motor as described in claim 1, characterized in that, The width of the first stator slot (6) near the stator yoke side is greater than the width near the air gap side.

4. The motor as described in claim 1, characterized in that, In the cross-section of the stator module, the second stator slot (7) is triangular arched.

5. The motor as described in claim 1, characterized in that, The armature winding (4) is a concentrated winding.

6. The motor as described in claim 1, characterized in that, The motor is either an external rotor internal stator motor or an external stator internal rotor motor.

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