Transverse flux linear motor with y-core and halbach array

Abstract

The transverse flux linear motor with Y type core and Halbach array belongs to the field of permanent magnet linear motor design, and aims to solve the problems of low utilization rate of permanent magnet, large magnetic flux leakage and insufficient power density of the traditional transverse flux linear motor. The transverse flux linear motor comprises a primary part and a secondary part. The primary part comprises a plurality of stator cores arranged in sequence along the axial direction, each stator core is provided with three circumferentially distributed armature modules, each armature module comprises long and short armature teeth and armature windings, the long and short teeth are designed with inclined air gaps and magnetic pole shoes, and the secondary part comprises Y type secondary pole cores and Halbach permanent magnet arrays on the surfaces of the Y type secondary pole cores, the permanent magnet arrays are circumferentially divided into three regions, and the three regions correspond to the three-phase armature modules of the primary part respectively, each region of permanent magnet is composed of an N pole and an S pole staggered in the axial direction, and adjacent regions are staggered in the axial direction.

Description

TECHNICAL FIELD

[0001] The application relates to the field of permanent magnet linear motor design, in particular to a transverse flux linear motor adopting Y-shaped cores and Halbach arrays. BACKGROUND

[0002] The transverse flux linear permanent magnet motor adopts a unique three-dimensional magnetic circuit structure, the magnetic field path plane of which is perpendicular to the motion direction, thereby realizing decoupling of the circuit and the magnetic circuit. The design makes the transverse flux linear permanent magnet motor have the characteristics of high thrust density, flexible design, convenient control and excellent low-speed performance compared with the traditional linear motor. The transverse flux linear permanent magnet motor shortens the magnetic circuit length, reduces the amount of ferromagnetic material and iron loss, and improves the power density, and is especially suitable for low-speed and high-power driving occasions.

[0003] The traditional transverse flux linear motor still faces some key problems. For example, the power factor is low, which is mainly caused by low utilization of permanent magnets, serious leakage between permanent magnets and large leakage of armature windings. Some topological structures also have the problems of small air gap area and low thrust density, which are also caused by low utilization of permanent magnets and large leakage. In addition, the complex three-dimensional structure also generally leads to high copper consumption and high cost. Therefore, it is very important to improve the topological structure, improve the space utilization of permanent magnets, and further improve the linear load and magnetic load in a certain space to improve the thrust density. SUMMARY

[0004] In order to solve the problems of low utilization of permanent magnets, large leakage and insufficient power density of the traditional transverse flux linear motor, the application provides a transverse flux linear motor adopting Y-shaped cores and Halbach arrays.

[0005] The transverse flux linear motor adopting Y-shaped cores and Halbach arrays comprises a primary part and a secondary part.

[0006] The primary part comprises a plurality of stator cores arranged in sequence along the axial direction, wherein n is an integer greater than or equal to 1, three armature modules are uniformly distributed on each stator core in the circumferential direction, one phase armature winding is arranged on each armature module, the armature winding is wound on the armature teeth with long and short teeth, and the center axial distance between adjacent two stator cores is a pole pitch .

[0007] The secondary part comprises a Y-shaped secondary pole core and a secondary permanent magnet; the Y-shaped secondary pole core has three radially extending branches, each branch comprising a radially extending neck and a radially outer end head, the head being larger in circumferential dimension than the neck; the secondary permanent magnet is a Halbach permanent magnet array attached to the surface of the Y-shaped secondary pole core, the Halbach permanent magnet array being evenly divided into three regions in the circumferential direction, corresponding to the three-phase armature modules of the primary part respectively; the permanent magnet sub-arrays of each region are arranged alternately in the axial direction with NS poles, and the distance between adjacent permanent magnets is a pole distance ; and the permanent magnets of adjacent phase regions are staggered in the axial direction by a distance.

[0008] Preferably, each of the armature modules comprises two long armature teeth and two short armature teeth; the long armature teeth are configured to be radially opposite to the neck region of the branch, and the short armature teeth are configured to be radially opposite to the head region of the same branch;

[0009] The armature windings of the same armature module are connected in series in turn, wherein the current circulation directions of the armature windings wound on the two long armature teeth of the same armature module are the same, the current circulation directions of the armature windings wound on the two short armature teeth of the same armature module are the same, and the current circulation directions of the armature windings wound on the long armature teeth and the short armature teeth are opposite.

[0010] Preferably, in all armature modules, the current circulation directions of the armature windings on the positionally corresponding long armature teeth in the axially adjacent armature modules are opposite, and the current circulation directions of the armature windings on the positionally corresponding short armature teeth in the axially adjacent armature modules are opposite.

[0011] Preferably, the ends of the long armature teeth and the short armature teeth are inclined structures to form inclined air gaps, and the ends of the long armature teeth and the short armature teeth are provided with axial magnetic concentration pole shoes.

[0012] Preferably, the number of turns of the armature windings on the long armature teeth and the short armature teeth is different.

[0013] Preferably, the three branches of the Y-shaped secondary pole core are evenly and symmetrically distributed in the circumferential direction.

[0014] Preferably, the secondary permanent magnet comprises:

[0015] a first permanent magnet group and a second permanent magnet group distributed in the neck region of the branch, the first permanent magnet group and the second permanent magnet group being in a trapezoidal structure;

[0016] a third permanent magnet group distributed in the head region of the branch;

[0017] ​​The first permanent magnet group, the second permanent magnet group and the third permanent magnet group located in the same arm constitute a permanent magnet subarray, and the permanent magnet subarrays of each region are arranged alternately by N poles and S poles in the axial direction,

[0018] Preferably, the first permanent magnet group, the second permanent magnet group and the third permanent magnet group are composed of three-section Halbach array permanent magnets.

[0019] Preferably, the yoke part of the stator core of the primary part is connected with the armature teeth of the same phase, and the stator cores of each phase are connected through the magnetic isolation block.

[0020] Preferably, the stator core of the primary part and the Y-shaped secondary core are laminated by silicon steel sheets.

[0021] The beneficial effects of the present application are:

[0022] 1. Core performance breakthrough: high thrust density and efficiency

[0023] The present application adopts a unique full winding design and Y-shaped secondary core, so that all secondary permanent magnets corresponding to the primary at the same time participate in work. Compared with the traditional transverse flux linear motor, the utilization rate of permanent magnets is doubled, which fundamentally improves the thrust density of the motor, while maintaining the advantages of electromagnetic decoupling, high efficiency and convenient control of the traditional transverse flux motor.

[0024] 2. Extreme optimization of structure and space

[0025] Through the precise spatial adaptation of the long and short teeth of the armature teeth and the neck / head of the Y-shaped core, combined with the design of the inclined air gap and the axial magnetic pole shoe, the effective area of the air gap and the facing area of the permanent magnet and the core are greatly increased. The actual measurement shows that compared with the same size cylindrical secondary motor, the space utilization rate of the permanent magnet of the present application can be improved by 74.4%, the volume of the secondary core is reduced by 51.8%, and the winding area is increased by 33%, realizing the unity of lightweight and high space utilization.

[0026] 3. Improved running performance and control quality

[0027] The Halbach permanent magnet array effectively reduces the width of the Y-shaped core neck and the thickness of the back iron due to its one-way magnetic aggregation characteristics, further reducing the weight of the mover and the amount of iron core material, while making the air gap magnetic density waveform better and the harmonics less, which helps to reduce thrust fluctuation and operating noise.

[0028] The primary part of the motor is modularly designed, and the magnetic isolation blocks are used to connect between each phase, which effectively reduces the mutual inductance between phases, reduces the difficulty of motor control, and improves the fault tolerance of the system. ​​​

[0029] 4. Design flexibility and wide applicability

[0030] This invention inherits the inherent advantages of decoupling the circuit and magnetic circuit of a transverse flux motor. Its electromagnetic loads can be designed independently, offering extremely high design freedom and the ability to flexibly adapt to the needs of different application scenarios. The motor can adopt a primary stator and secondary mover structure, functioning as both a motor and a generator, thus having a wide range of applications. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the axial cross-sectional structure of the motor of the present invention;

[0032] Figure 2 This is a three-dimensional structural diagram of the motor of the present invention;

[0033] Figure 3 This is a side view of the motor of the present invention;

[0034] Figure 4 This is a schematic diagram of the armature winding structure of the primary section, taking phase A winding as an example;

[0035] Figure 5 This is a schematic diagram showing the unfolded magnetic pole plane of a secondary permanent magnet;

[0036] Figure 6 This is a three-dimensional structural diagram of a secondary permanent magnet;

[0037] Figure 7 The motor of this invention Magnetic flux path diagram at any time; in the diagram, the red line path indicates the magnetic flux direction of the secondary part, the black arrow indicates the magnetization direction of the permanent magnet, and the green line path indicates the magnetic flux direction of the primary part.

[0038] Figure 8 The motor of this invention Magnetic flux path diagram at any time;

[0039] Figure 9 This is a schematic diagram of the armature teeth in the primary section having a magnetic pole shoe;

[0040] Figure 10 This is a schematic diagram of the structure of a Y-type secondary iron core. Detailed Implementation

[0041] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0043] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention.

[0044] Specific Implementation Method 1: The following is combined with... Figures 1 to 10 This embodiment describes a transverse flux linear motor using a Y-type iron core and a Halbach array, comprising a primary section and a secondary section.

[0045] The primary part includes Stator cores 1 arranged sequentially along the axial direction. The value is an integer greater than or equal to 1. Each stator core 1 has three armature modules 2 evenly distributed circumferentially. Each armature module 2 has one phase armature winding 4, which is wound on armature teeth 3 with a design of long and short teeth. The axial distance between the centers of two adjacent stator cores 1 is the pole pitch. ;

[0046] The secondary section includes a Y-shaped secondary core 6 and a secondary permanent magnet 5. The Y-shaped secondary core 6 has three radially extending arms, each arm comprising a radially extending neck 6a and a radially outer head 6b, the head 6b being larger in the circumferential direction than the neck 6a. The secondary permanent magnet 5 is a Halbach permanent magnet array, attached to the surface of the Y-shaped secondary core 6. The Halbach permanent magnet array is uniformly divided into three regions along the circumference, corresponding to the three-phase armature module 2 of the primary section. The permanent magnet subarrays in each region are arranged axially with alternating N, N poles, and the distance between adjacent permanent magnets is the pole pitch. Furthermore, the permanent magnets in adjacent phase regions are axially offset. distance.

[0047] Basic parameters of the example:

[0048] In this embodiment, the axial quantity of the stator core 1 in the primary section... The secondary permanent magnet has 6 poles in each pole region along the axial direction. N poles and There are 12 S poles, and the pole distance is... It is 20 mm. The motor adopts a short primary and long secondary structure with a fixed primary stator and a moving secondary rotor.

[0049] Overall structure description of the motor:

[0050] See Figure 1 and Figure 2The transverse flux linear motor with Y-shaped iron core and Halbach array described in this invention is mainly composed of a primary part and a secondary part.

[0051] The primary section comprises six stator cores 1 arranged sequentially along the axial direction. All stator cores 1 are fixed by brackets (not shown in the figure). Each stator core 1 is made of stacked high-permeability silicon steel sheets, and has three identical armature modules 2 evenly distributed circumferentially on it, corresponding to phases A, B, and C respectively. The axial distance between the centers of two adjacent stator cores 1 is equal to the pole pitch. That is, 20 millimeters.

[0052] The secondary section extends through the primary section, maintaining a certain oblique air gap with it. The secondary section includes a Y-shaped secondary core 6 and a secondary permanent magnet 5. The Y-shaped secondary core 6 is also made of stacked silicon steel sheets, and it has three circumferentially oriented... The arms are evenly and symmetrically distributed, each extending radially outward from a common yoke (i.e., a central yoke). Each arm is clearly divided into a neck with a trapezoidal cross-section and a head with a rectangular cross-section, wherein the head is significantly larger in the circumferential direction than the neck, thus forming a Y-shaped structure.

[0053] Detailed structure of the beginner section:

[0054] See Figure 2 , Figure 3 and Figure 9 Each armature module 2 includes two long armature teeth 3a and two short armature teeth 3b. Both the long armature teeth 3a and the short armature teeth 3b extend radially inward. Two key design features are incorporated at the ends of the armature teeth (i.e., the pole shoe portion): firstly, the end face is inclined, creating an oblique air gap between it and the secondary permanent magnet 5 (see...). Figure 1 , Figure 2 This increases the effective area of ​​the air gap; secondly, a magnetic focusing design is implemented in the axial direction, with an axial magnetic focusing pole shoe 8, which diverges into a truncated quadrangular structure (see...). Figure 9 This design significantly increases the facing area between the armature teeth and the permanent magnet. Calculations show that this axial focusing pole shoe design can increase the facing area by approximately [percentage missing]. Due to the complexity of this three-dimensional structure, it is recommended to manufacture it using a single-piece soft magnetic composite material (SMC), or to achieve it using other single-piece soft magnetic processes.

[0055] Armature winding 4 is wound on long and short armature teeth. As an optimized design, the number of turns of the winding wound on the long armature tooth 3a and the winding wound on the short armature tooth 3b can be different, in order to balance the fluctuations of radial magnetic pull and axial thrust generated during motor operation and improve the smoothness of operation.

[0056] Winding connection method:

[0057] See Figure 4 Taking phase A as an example, the relationship between the winding connection and the current direction is explained. The armature winding 4 wound on armature module 2 is connected in series.

[0058] Within the same armature module (circumferential relationship): windings A1 and A4 wound on the two long armature teeth 3a have the same current winding direction because their corresponding neck permanent magnets have the same polarity; similarly, windings A2 and A3 wound on the two short armature teeth 3b also have the same current winding direction. However, the current winding direction of windings A1 and A4 wound on the long armature teeth 3a is opposite to that of windings A2 and A3 wound on the short armature teeth 3b.

[0059] Between different armature modules (axial relationship): In axially adjacent armature modules 2, the windings on the corresponding long armature teeth 3a (or short armature teeth 3b) have opposite current winding directions.

[0060] This specific connection method, characterized by "long teeth in the same direction, short teeth in the same direction, long and short teeth in opposite directions, and adjacent axial teeth in opposite directions," ensures that the traveling wave magnetic field generated in the primary stage can interact efficiently with the secondary Halbach permanent magnet array, producing a stable and powerful unidirectional axial thrust.

[0061] Detailed structure of the secondary part:

[0062] See Figure 1 , Figure 4 , Figure 5 , Figure 6 and Figure 10 The secondary permanent magnet 5 has a surface-mount structure and is tightly attached to the neck side and head end face of all the arms of the Y-shaped secondary iron core 6.

[0063] The secondary permanent magnet 5 is uniformly divided into three functional regions, A, B, and C, along the circumference, corresponding one-to-one with the three-phase armature module of the primary part. The permanent magnets in each region constitute a complete permanent magnet subarray.

[0064] Specifically, each arm includes a radially extending neck 6a and a radially outer head 6b, the head 6b being larger in the circumferential direction than the neck 6a (see...). Figure 10 Its permanent magnet subarray includes:

[0065] The first permanent magnet group 5-1 and the second permanent magnet group 5-2 are respectively attached to the two sides of the neck of the support arm. To perfectly fit the trapezoidal contour of the neck 6a, these two groups of permanent magnets are designed with a trapezoidal structure (see...). Figure 6 ).

[0066] The third permanent magnet assembly 5-3 is attached to the outer end face of the arm head 6b.

[0067] The three permanent magnet groups located on the same arm together form a three-segment Halbach array in the circumferential direction (see...). Figure 1 , Figure 4 This strengthens the magnetic field on the air gap side and weakens the magnetic field on the iron core side, thus achieving unidirectional magnetic focusing.

[0068] In the axial direction, each region's permanent magnet subarray consists of =6 equivalent "N poles" and =It is composed of 6 equivalent "S pole" permanent magnet units arranged in an alternating pattern. The sum of the axial lengths of an N pole and an adjacent S pole is the pole pitch. (20 mm). Crucially, as... Figure 5 and Figure 6 As shown, the permanent magnet subarrays of the three adjacent phase regions A, B, and C are not aligned axially, but are staggered sequentially. (Right now The distance is (in millimeters). This design is used to match the current phase difference of the three-phase symmetrical windings and is key to generating smooth linear thrust.

[0069] Magnetic circuit and working process:

[0070] See Figure 7 and Figure 8 They respectively showed Time and time( The magnetic flux path (for the motor's operating speed) is shown. Taking phase A as an example, when a sinusoidal current is applied, the magnetomotive force generated by the current interacts with the magnetic field generated by the permanent magnet. The main magnetic flux (as shown by the dotted line in the figure) flows through the long armature tooth 3a, the primary yoke, and the short armature tooth 3b, passes through the air gap, enters the secondary permanent magnet 5 and the Y-type secondary iron core 6, and forms a closed loop through their common yoke. As the current phase changes and the mover moves, the magnetic flux path and direction change periodically, thereby generating a continuous and stable axial electromagnetic thrust on the mover.

[0071] Other design optimizations:

[0072] See Figure 1 The yoke of the primary stator core 1 connects two long armature teeth 3a and two short armature teeth 3b of the same phase. Armature modules 2 of different phases are mechanically connected via magnetic isolation blocks 7. This magnetic isolation design effectively reduces magnetic coupling and mutual inductance between phases, lowers the difficulty of motor control, and improves the system's fault tolerance.

[0073] Application scenarios:

[0074] The motor described in this embodiment can be used as a high-performance motor to directly drive loads that require high precision and high response speed linear motion, such as precision machining platforms and electromagnetic catapults; it can also be used as a generator for energy capture in linear reciprocating motion scenarios such as wave energy power generation.

[0075] While the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. A transverse flux linear motor employing a Y-core and a Halbach array, characterized in that, The primary part and the secondary part are included. The primary part comprises h a plurality of stator cores (1) arranged in sequence along the axial direction, the number of the stator cores (1) being an integer greater than or equal to 1, three armature modules (2) being uniformly distributed in the circumferential direction on each of the stator cores (1), one phase armature winding (4) being arranged on each of the armature modules (2), the armature winding (4) being wound on an armature tooth (3) designed with long and short teeth, and the center axial distance between two adjacent stator cores (1) being a pole pitch ​ The secondary part comprises a Y-shaped secondary core (6) and a secondary permanent magnet (5); the Y-shaped secondary core (6) has three radially extending branches, each of which comprises a radially extending neck (6a) and a radially outer head (6b), the head (6b) being larger in circumferential dimension than the neck (6a); the secondary permanent magnet (5) is a Halbach permanent magnet array attached to the surface of the Y-shaped secondary core (6), the Halbach permanent magnet array being uniformly divided into three regions in the circumferential direction, corresponding to the three-phase armature modules (2) of the primary part respectively; the permanent magnet sub-arrays of each region are alternately arranged in the axial direction with NS poles, and the distance between adjacent permanent magnets is a pole distance ; and the permanent magnets of adjacent phase regions are axially staggered by a distance. Each of the armature modules (2) includes two long armature teeth (3a) and two short armature teeth (3b); the long armature teeth (3a) are configured to be opposite to the neck region of the branch in the radial direction, and the short armature teeth (3b) are configured to be opposite to the head region of the same branch in the radial direction. The armature windings (4) of the same armature module (2) are connected in series in turn, wherein the armature windings (4) wound on the two long armature teeth (3a) of the same armature module (2) have the same current circulation direction, the armature windings (4) wound on the two short armature teeth (3b) of the same armature module (2) have the same current circulation direction, and the armature windings (4) wound on the long armature teeth (3a) have the opposite current circulation direction compared with the armature windings (4) wound on the short armature teeth (3b). The secondary permanent magnet (5) includes: The first permanent magnet group (5-1) and the second permanent magnet group (5-2) are distributed in the neck region of the branch, and the first permanent magnet group (5-1) and the second permanent magnet group (5-2) have a trapezoidal structure; The third permanent magnet group (5-3) is distributed in the head region of the branch; Wherein, the first permanent magnet group (5-1), the second permanent magnet group (5-2) and the third permanent magnet group (5-3) located in the same arm constitute a permanent magnet subarray, and the permanent magnet subarray of each region is composed of j N poles and j S poles staggered in the axial direction, .

2. The transverse flux linear motor employing Y-core with Halbach array according to claim 1, characterized in that, In all armature modules (2), in the axially adjacent armature modules (2), the armature windings (4) on the position corresponding long armature teeth (3a) have opposite current circulation directions, and the armature windings (4) on the position corresponding short armature teeth (3b) have opposite current circulation directions.

3. The transverse flux linear motor employing Y-core with Halbach array according to claim 1, characterized in that, The ends of the long armature teeth (3a) and the short armature teeth (3b) are inclined structures to form inclined air gaps, and the ends of the long armature teeth (3a) and the short armature teeth (3b) are provided with axial magnetic concentration pole shoes (8).

4. The transverse flux linear motor employing Y-core with Halbach array according to claim 1, characterized in that, The number of turns of the armature windings (4) on the long armature teeth (3a) and the short armature teeth (3b) is different.

5. The transverse flux linear motor employing Y-core with Halbach array according to claim 1, characterized in that, The three branches of the Y-shaped secondary core (6) are uniformly and symmetrically distributed in the circumferential direction at an angle of 120°.

6. The transverse flux linear motor employing Y-core with Halbach array according to claim 1, characterized in that, The first permanent magnet group (5-1), the second permanent magnet group (5-2), and the third permanent magnet group (5-3) are all composed of three-section halbach array permanent magnets.

7. The transverse flux linear motor employing Y-core with Halbach array according to claim 1, characterized in that, The yoke of the stator core (1) of the primary part is connected to the armature teeth (3) of the same phase, and the stator cores (1) of each phase are connected through the magnetic isolation block (7).

8. The transverse flux linear motor employing a Y-core with a Halbach array according to claim 1, wherein, The stator core (1) of the primary part and the Y-shaped secondary core (6) are made of silicon steel sheets.

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