A new type of flux reversal permanent magnet double salient pole motor

Abstract

The present invention discloses a novel flux reversal permanent magnet double salient pole motor, comprising a stator core, a rotor core, an armature winding and a rotating shaft; the rotor core is arranged inside the stator core, and the rotor core can rotate relative to the stator core; the rotating shaft is arranged inside the rotor core, and the rotating shaft can rotate together with the rotor core; the rotor core is provided with rotor poles; the stator core is provided with stator poles; the armature winding is composed of a plurality of armature coils connected in series, in parallel or in mixed connection; each armature coil is wound across a plurality of stator poles; permanent magnets with different magnetization directions are placed on the corresponding yokes of the adjacent stator slots in the middle. The motor not only reduces the amount of permanent magnets and armature windings, but also further increases the power density of the motor and reduces the torque pulsation of the double salient pole motor.

Description

Technical Field

[0001] The present invention relates to the technical field of motors, and in particular to a novel flux-reversing permanent magnet double-salient-pole motor. Background Art

[0002] The structure of the traditional flux reversal permanent magnet double salient pole motor is as follows: the stator and rotor are both salient pole structures, the permanent magnets and armature windings are placed on the stator side, and the rotor core has neither permanent magnets nor windings; the armature coil of each phase is wound across two stator salient poles and the permanent magnets sandwiched between them, the sandwiched permanent magnets are magnetized radially, and the armature coils of different phases are adjacent in sequence. When the rotor rotates to different positions, the magnetic flux interlinked with the stator windings of each phase presents a bipolar change. This motor has the characteristics of simple structure, high power density and torque density, and has received extensive attention and research from scholars at home and abroad. Its design and control technology are becoming more and more mature, and it has good application prospects in industries such as wind power generation, aviation and automobiles. However, this type of motor uses more permanent magnets, and the utilization rate of permanent magnets is not high, and the manufacturing cost is high. Summary of the invention

[0003] In order to reduce the cost of the motor, the present invention provides a novel flux reversal permanent magnet double-salient pole motor, which not only reduces the amount of permanent magnets and armature windings used, but also further increases the motor power density and reduces the torque pulsation of the double-salient pole motor.

[0004] The technical solution adopted by the present invention is:

[0005] A novel flux-reversing permanent magnet double-salient pole motor comprises a stator core, a rotor core, an armature winding and a rotating shaft; the rotor core is arranged inside the stator core, and the rotor core can rotate relative to the stator core; the rotating shaft is arranged inside the rotor core, and the rotating shaft can rotate together with the rotor core; the rotor core is provided with rotor poles; the stator core is provided with stator poles; the armature winding is composed of a plurality of armature coils connected in series, in parallel or in mixed connection; each armature coil is wound across a plurality of stator poles; permanent magnets with different magnetization directions are placed on the corresponding yokes of adjacent stator slots in the middle.

[0006] Further, each armature coil is wound across three stator poles.

[0007] Furthermore, the stator core is a salient pole structure, and the pole widths of the stator poles are evenly distributed.

[0008] Furthermore, the stator core is a salient pole structure, and the pole width of the stator pole is unevenly distributed, the pole width of the middle stator pole of each phase is wider, and the pole width of the stator poles on both sides is narrower.

[0009] Furthermore, the number of stator poles p s For 3N*m indivual, N is a positive integer, m is the number of phases of the motor, and the pole pitch of adjacent stator poles of the same phase is [ w s* 180° / (πR SI ), 180° / ( Nm )- w s* 90° / (πR SI )] can be adjusted between, where R SI is the inner diameter of the stator, w s is the pole width of the stator.

[0010] Furthermore, the rotor core is a salient pole structure, the pole width of the rotor pole is evenly distributed, and the rotor pole width is 1 to 2 times the minimum stator pole width.

[0011] Furthermore, the armature coil includes two parts: one part is wound across three stator poles, and the other part is wound around the middle stator pole, and the two parts are connected in series.

[0012] Furthermore, the same armature coil spans across multiple stator poles to form a stator pole group, and auxiliary teeth are attached between the stator pole groups, and no coil is wound on the auxiliary teeth.

[0013] Beneficial effects of the present invention:

[0014] 1. Compared with the traditional flux reversal permanent magnet double salient pole motor, under the conditions of the same motor structure size and torque density, the total number of armature winding turns required by the motor of the present invention can be reduced by about 30%, thereby reducing the motor cost and winding loss and improving the motor efficiency.

[0015] 2. Compared with the conventional flux reversal permanent magnet double salient pole motor, under the condition of the same motor structure size, the motor of the present invention has a larger space between the stator poles where the armature coils of each phase are wound, and the space can also be used to wind the armature coils, thereby increasing the total number of turns of the armature coils and improving the torque density of the motor; in addition, the space can also be used to place a cooling device to reduce the temperature rise of the motor;

[0016] 3. Compared with the traditional flux reversal permanent magnet double salient pole motor, the permanent magnets used in the present invention are placed in pairs on the stator yoke, and the magnetization directions of the permanent magnets are opposite, which has better magnetic concentration performance and improves the utilization rate of the permanent magnets. Therefore, under the same torque density, the amount of permanent magnets can be reduced; under the same conditions of motor structure size, armature winding and permanent magnet amount, a larger induced electromotive force and electromagnetic torque can be obtained, thereby improving the power density of the motor;

[0017] 4. Compared with the traditional flux reversal permanent magnet double salient pole motor, the motor described in the present invention has increased design freedom. By optimizing parameters such as the pole width of different stator salient poles and the stator salient pole spacing inside the armature coil, the torque density and power density can be further improved.

[0018] In summary, the present invention adopts a reasonable configuration of the armature winding position and optimizes the added design parameters, which can improve the power density and torque density of the motor. The motor has a simple structure, there are no permanent magnets on the stator and rotor, the motor has high reliability, and is suitable for high-speed and harsh working environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic axial cross-sectional view of a three-phase 18 / 10-pole flux-reversed permanent magnet double-salient pole motor in Embodiment 1 of the present invention;

[0020] Figure 2 The no-load induced electromotive force diagram of the three-phase winding of the motor in the first embodiment of the present invention;

[0021] Figure 3 is a harmonic analysis diagram of the induced electromotive force of the A-phase winding of the motor in the first embodiment of the present invention;

[0022] Figure 4 This is a schematic axial cross-sectional view of a stator skew slot type four-phase 12 / 10-pole flux reversal permanent magnet double-salient pole motor in Embodiment 2 of the present invention;

[0023] Figure 5 This is a schematic axial cross-sectional view of a 12 / 7-pole three-phase permanent magnet double-salient-pole motor with auxiliary teeth in Embodiment 3 of the present invention;

[0024] Figure 6 This is a schematic axial cross-sectional view of a three-phase 12 / 7-pole permanent magnet double-salient-pole motor with stator auxiliary teeth in Embodiment 4 of the present invention;

[0025] Figure 7 This is a schematic axial cross-sectional view of a three-phase 18 / 10-pole stator skew slot type flux reversal permanent magnet double-salient pole motor in Embodiment 5 of the present invention;

[0026] Figure 8 This is a schematic axial cross-sectional view of a four-phase 12 / 7-pole permanent magnet double-salient pole motor in Embodiment 6 of the present invention.

[0027] The drawings are only used for illustrative purposes and should not be construed as limitations on this patent. In order to better illustrate this embodiment, some parts of the drawings may be omitted, enlarged, or reduced, and do not represent the size of the actual product. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0028] Specific implementation method

[0029] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0030] like Figure 1 , Figure 4 , Figure 5 , Figure 6 , Figure 7 or Figure 8 As shown, the present invention provides a new type of flux reversal permanent magnet double-salient pole motor, including a stator core 1, a rotor core 2, an armature winding and a rotating shaft; the rotor core 2 is arranged inside the stator core 1, and the rotor core 2 can rotate relative to the stator core 1; the rotating shaft is arranged inside the rotor core 2, and the rotating shaft can rotate together with the rotor core 2; the rotor core 2 is provided with rotor poles; the stator core 1 is provided with stator poles; the armature winding is composed of a plurality of armature coils 4 connected in series, in parallel or in mixed connection; each armature coil 4 is wound across three stator poles; permanent magnets 5 with different magnetization directions are placed on the corresponding yokes of the adjacent stator slots in the middle.

[0031] The stator core 1 is a salient pole structure, and the pole width of the stator pole is uniformly distributed. The pole width of the stator pole can also be unevenly distributed, with the pole width of the middle stator pole of each phase being wider and the pole width of the stator poles on both sides being narrower.

[0032] Number of stator poles p s For 3 N*m indivual, N is a positive integer, m is the number of phases of the motor, and the pole pitch of adjacent stator poles of the same phase is [ w s* 180° / (πR SI ), 180° / ( Nm )- w s* 90° / (πR SI )] can be adjusted between, where R SI is the inner diameter of the stator, w s is the pole width of the stator.

[0033] The rotor core 2 is a salient pole structure, the pole width of the rotor pole is evenly distributed, and the rotor pole width is 1 to 2 times the stator pole width. The rotor pole adopts a parallel tooth, a fan-shaped tooth structure or a T-shaped tooth eccentric structure.

[0034] The armature coil 4 is a concentrated winding wound across three stator poles. The armature coil 4 can also adopt the following structure, including two parts: one part is wound across three stator poles, and the other part is wound around the middle stator pole, and the two parts are connected in series.

[0035] The stator core 1 and the rotor core 2 are both formed by stamping silicon steel sheets.

[0036] Six specific motor embodiments are used below for further explanation.

[0037] Embodiment 1:

[0038] like Figures 1 to 3 As shown, this embodiment provides a novel flux reversal permanent magnet double salient pole motor, specifically a three-phase 18 / 10 pole flux reversal permanent magnet double salient pole motor.

[0039] like Figure 1 As shown, a pair of permanent magnets with opposite magnetization directions are placed in the stator yoke corresponding to the two stator slots in the middle of each stator pole group (definition: the three stator poles spanned by the same armature coil constitute a stator pole group). The stator pole can be composed of multiple units spliced ​​together. The center lines of the three stator poles inside the stator pole group all pass through the center of the circle.

[0040] like Figure 2 The no-load induced electromotive force of the three-phase winding shown, and Figure 3 The harmonic analysis of the induced electromotive force of the A-phase winding shown in the figure shows that a three-phase symmetrical back electromotive force with good sinusoidality can be obtained.

[0041] Embodiment 2:

[0042] This embodiment provides a novel flux reversal permanent magnet double salient pole motor, specifically a stator skew slot type four-phase 12 / 10 pole flux reversal permanent magnet double salient pole motor.

[0043] like Figure 4 As shown, the three stator pole center lines inside the stator pole group are parallel to each other.

[0044] Embodiment three:

[0045] This embodiment provides a novel flux reversal permanent magnet double-salient pole motor, specifically a 12 / 7-pole three-phase permanent magnet double-salient pole motor with auxiliary teeth.

[0046] like Figure 5 As shown, the center lines of the three stator poles inside the stator pole group are parallel to each other, and the permanent magnets extend into the stator slots. Auxiliary teeth 6 are attached between the stator pole groups, and no coils are wound on the auxiliary teeth 6. By adjusting the width of the auxiliary teeth, the motor output can be increased or the torque pulsation can be reduced.

[0047] Embodiment 4:

[0048] This embodiment provides a novel flux reversal permanent magnet double salient pole motor, specifically a three-phase 12 / 7 pole permanent magnet double salient pole motor with stator auxiliary teeth.

[0049] like Figure 6As shown in the figure, (1) the permanent magnets extend into the stator slots to increase the power density. (2) There are auxiliary teeth between the stator pole groups. By optimizing the stator auxiliary teeth, the torque can be effectively improved.

[0050] Embodiment five:

[0051] This embodiment provides a novel flux reversal permanent magnet double salient pole motor, specifically a three-phase 18 / 10 pole stator skew slot type flux reversal permanent magnet double salient pole motor.

[0052] like Figure 7 As shown, multiple same-phase windings are connected in series or in parallel.

[0053] Embodiment six:

[0054] This embodiment provides a novel flux reversal permanent magnet double salient pole motor, specifically a four-phase 12 / 7 pole permanent magnet double salient pole motor.

[0055] like Figure 8 As shown, the width of the stator teeth inside the stator pole group is different, and the tooth pitch inside the stator pole group is not equal to the tooth pitch between the stator pole groups. The motor performance is improved by optimizing the stator tooth width and pole pitch.

[0056] The above embodiments are only used to illustrate rather than limit the technical solutions of the present invention. Although the present invention is described in detail with reference to the above embodiments, those skilled in the art should understand that the present invention can still be modified or replaced by equivalents. Any modification or partial replacement that does not depart from the spirit and scope of the present invention should be included in the scope of the claims of the present invention.

[0057] If the words "first", "second", etc. are used in this document to limit components, those skilled in the art should know that the use of "first" and "second" is only to facilitate the description of the present invention and simplify the description. Unless otherwise stated, the above words have no special meaning.

[0058] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by the terms "upper", "lower", "front", "back", "left", "right", "inside", "outside", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the protection content of the present invention.

Claims

1. A novel flux reversal permanent magnet double salient pole motor, comprising a stator core, a rotor core, an armature winding and a rotating shaft; the rotor core is arranged inside the stator core, and the rotor core can rotate relative to the stator core; the rotating shaft is arranged inside the rotor core, and the rotating shaft can rotate together with the rotor core; the rotor core is provided with rotor poles; the stator core is provided with stator poles; the armature winding is composed of a plurality of armature coils connected in series, in parallel or in mixed connection; the characteristics are: Each armature coil is wound across three stator poles; permanent magnets with different magnetization directions are placed in the corresponding yokes of the adjacent stator slots in the middle; the number of stator poles p s For 3 N*m indivual, N is a positive integer, m is the number of phases of the motor; The armature coil comprises two parts: one part is wound across three stator poles, and the other part is wound around the middle stator pole, and the two parts are connected in series; The same armature coil spans across multiple stator poles to form a stator pole group. Auxiliary teeth are added between the stator pole groups, and no coil is wound on the auxiliary teeth.

2. The novel flux reversal permanent magnet double salient pole motor according to claim 1 is characterized in that: The stator core is a salient pole structure, and the pole widths of the stator poles are evenly distributed.

3. The novel flux reversal permanent magnet double salient pole motor according to claim 1 is characterized in that: The stator core is a salient pole structure, and the pole width of the stator pole is unevenly distributed, the pole width of the middle stator pole of each phase is wider, and the pole width of the stator poles on both sides is narrower.

4. The novel flux reversal permanent magnet double salient pole motor according to claim 2 or 3, characterized in that: The pole pitch of adjacent stator poles of the same phase is [ w s* 180° / (πR SI ), 180° / ( Nm )- w s* 90° / (πR SI )] can be adjusted between, where R SI is the inner diameter of the stator, w s is the pole width of the stator.

5. The novel flux reversal permanent magnet double salient pole motor according to claim 1 is characterized in that: The rotor core is a salient pole structure, the pole width of the rotor pole is evenly distributed, and the rotor pole width is 1 to 2 times the minimum stator pole width.

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