Axial misalignment type polygonal permanent magnet synchronous linear motor

Abstract

This invention relates to an axially offset polygonal permanent magnet synchronous linear motor, belonging to the field of permanent magnet motors. The invention addresses the problems of high end forces and high thrust fluctuations in existing polygonal permanent magnet synchronous linear motor structures. The invention comprises four primary modules arranged in a polygonal layout on the outer side; and a secondary module located at the center of the polygonal layout, which is a cuboid frame structure with open ends, equidistant from all the primary modules in terms of air gap. A primary module on one side of the motor is selected as a reference module, and the initial positions of the remaining primary modules are offset axially by a distance ΔL from the reference module, forming an axially offset structure. The three ΔL values ​​of the motor may be equal or unequal. When two opposing modules have the same ΔL, it can counteract the normal force. The winding arrangement is reconstructed according to the axial offset distance, which can offset the change in winding phase after offset, thereby weakening the end forces and reducing thrust fluctuations.

Description

Technical Field

[0001] This invention relates to an axially misaligned polygonal permanent magnet synchronous linear motor, belonging to the field of permanent magnet motors. Background Technology

[0002] Permanent magnet linear motors overcome the limitations of traditional rotary motors that rely on transmission devices, directly generating linear motion. They are characterized by their compact structure and high energy transfer efficiency, and are widely used in high-end manufacturing, transportation, automation, and other fields. Among them, polygonal permanent magnet synchronous linear motors, with their similar shape to cylindrical permanent magnet linear motors but with better manufacturability, and their modular structure allowing for more flexible design, have garnered significant attention across various industries. Furthermore, when a motor fails, only the damaged module needs to be repaired or replaced, eliminating the need for complete machine disposal and reducing maintenance and repair costs.

[0003] The special problem that distinguishes permanent magnet synchronous linear motors from rotary motors is that the magnetic field changes abruptly at the end of the linear motor when the end is disconnected, resulting in large thrust fluctuations. This is one of the reasons that limits the practical application of polygonal permanent magnet synchronous linear motors.

[0004] For conventional polygonal permanent magnet synchronous linear motors, see Figure 3 As shown, the motor consists of four primary modules arranged in a rectangular layout on the outer edges and a secondary unit located at the center of the rectangular layout. The secondary unit is equidistant from each primary module. Each module is fixedly connected via a housing and windings. The armature windings of each primary module are all circularly wound, and the winding arrangement is identical to the initial position of the primary modules. The motor forms a symmetrical structure along the circumference. Therefore, the total end force of the motor and the resultant end force of each primary module are algebraically superimposed, resulting in a large end force and high thrust fluctuation. Reducing the end force of the linear motor, improving thrust fluctuation, reducing control difficulty, and enhancing system stability are crucial for this type of permanent magnet synchronous linear motor. Summary of the Invention

[0005] To address the issues of large end forces and high thrust fluctuations in existing polygonal permanent magnet synchronous linear motor structures, this invention provides an axially misaligned polygonal permanent magnet synchronous linear motor.

[0006] The present invention discloses an axially misaligned polygonal permanent magnet synchronous linear motor, comprising:

[0007] Four primary modules are arranged in a polygonal layout on the outside;

[0008] And a secondary module, located at the center of the polygon layout, is a cuboid frame structure with openings at both ends, and has the same air gap distance as all primary modules;

[0009] Select any primary module on one side of the motor as the reference module, and set the initial positions of the other primary modules to be offset axially by a distance ΔL based on the reference module, forming an axial misalignment structure; the three ΔL values ​​of the motor are equal or unequal, and the phase change caused by the axial misalignment is offset by reconfiguring the windings.

[0010] Preferably, the secondary module includes a secondary core and permanent magnets. The secondary core is a cuboid frame structure with openings at both ends. The permanent magnets of the secondary module are arranged alternately along the N-S axis and have the same circumferential magnetization direction.

[0011] Preferably, the axial misalignment distance ΔL satisfies one of the following relationships:

[0012] Case 1: When β = 2α or β = -2α, based on the principle that the phase of the reference phase A is unchanged at 2kτ, each phase winding is moved by two slots in sequence to offset the phase change caused by axial misalignment, so that the phase of the back electromotive force of A is still 2kτ.

[0013] In the formula:

[0014] β is the electrical angle corresponding to the axial misalignment distance ΔL;

[0015] k is an integer, k = 0, ±1, ±2;

[0016] τ is the electric angle of the electrode distance, τ = 180°;

[0017] α is the slot electrical angle of the motor, α=360°×P / Z, where P is the number of pole pairs and Z is the number of slots;

[0018] Case 2: When β≠±2α, the windings of the remaining axially misaligned primary modules are reconstructed based on the principle that the phase 2kτ of the reference phase A remains unchanged, and the initial positions of the axially misaligned primary modules are adjusted according to the following formula:

[0019] β=2kτ-(mn)×α

[0020] In the formula:

[0021] (mn) represents the number of slots moved by each phase winding during the reconstruction of phase A winding; n and m are the slot numbers before and after the reconstruction of phase A winding, respectively. The remaining phases are moved by (mn) slots in sequence to maintain the symmetry of the three-phase windings.

[0022] (mn)×α is the phase offset caused by the reconfiguration of phase A winding;

[0023] The remaining phases are adjusted sequentially according to the slot potential star diagram to make the three-phase windings symmetrical;

[0024] Case 3: When β≠±2α, the windings of the axially misaligned primary module are reconstructed based on the phase change of the reference phase A as (2k+1)τ, and the initial position of the axially misaligned primary module is adjusted according to the following formula:

[0025] β=(2k+1)τ-(mn)×α

[0026] The remaining phases are adjusted sequentially according to the slot potential star diagram to make the three-phase windings symmetrical;

[0027] Case 4: When β≠±2α, the windings of the axially misaligned primary module are reconstructed based on the principle that the phase change of the reference phase A is close to kτ, and the initial position of the axially misaligned primary module is adjusted according to the following formula:

[0028] β+(mn)×α≈2kτ or (2k+1)τ.

[0029] Preferably, in cases one and two, the winding method and current direction of the misaligned module remain unchanged; in case three, the polarity of the secondary permanent magnet corresponding to the misaligned module is reversed, the winding current direction is changed, or the winding is wound in reverse; in case four, when the relationship β+(mn)×α≈2kτ is satisfied, the winding method and current direction of the misaligned module remain unchanged; when the relationship β+(mn)×α≈(2k+1)τ is satisfied, the polarity of the secondary permanent magnet corresponding to the misaligned module is reversed, the winding current direction is changed, or the winding is wound in reverse.

[0030] Preferably, the armature winding in the primary module is a single-layer winding or a double-layer winding, and can be constructed using a cross-tooth winding method or a combination of cross-tooth winding and ring winding.

[0031] Preferably, in case one, the winding arrangement and position of the two primary modules are the same, and the upper and lower and left and right primary modules are staggered by a fixed electrical angle of 2α or -2α. The winding adopts a combination of cross-tooth winding and ring winding. The winding of the end extension area formed by axial misalignment adopts cross-tooth winding, and the overlapping area of ​​the four primary modules adopts ring winding. In cases two, three, and four, the windings of the four primary modules uniformly adopt cross-tooth winding.

[0032] Preferably, the core of the primary module is made of silicon steel sheet, amorphous alloy material or soft magnetic composite material.

[0033] Preferably, the secondary core is made of a magnetically conductive material or a non-magnetically conductive material.

[0034] Preferably, when the secondary core uses a magnetically conductive material, silicon steel sheets, amorphous alloy materials, or soft magnetic composite materials are selected.

[0035] Preferably, when the secondary core is made of a non-magnetic material, aluminum alloy or titanium alloy is selected.

[0036] The beneficial effects of this invention are:

[0037] 1. This invention creates an axial misalignment structure by altering the initial position of the primary module, thereby changing the phase of the force at the end of the primary module. This reduces the overall resultant force at the end of the polygonal permanent magnet synchronous linear motor, improving the problem of large end force and high thrust fluctuation caused by end interruption in linear motors. Furthermore, by reconfiguring the winding arrangement, the impact of axial misalignment on the back EMF of the motor is reduced, ensuring the electromagnetic performance of the motor.

[0038] 2. In the motor of this invention, the armature winding can still use the ring winding method adopted by conventional polygonal permanent magnet synchronous linear motors. After satisfying the axial misalignment under certain constraints, for any primary module of the motor, only one end needs to be changed to cross-tooth winding. This retains the advantages of polygonal motors being able to use ring windings to the greatest extent, reducing the amount of end windings and facilitating wiring. This invention has the advantages of simple structure and good processing and assembly processability, and is suitable for applications of short primary and long secondary linear motors.

[0039] 3. The motor of the present invention can flexibly set the axial misalignment distance of each primary module, the armature winding arrangement, the permanent magnet polarity, etc. according to actual needs, and can realize a variety of variant structures, greatly expanding the design flexibility. Attached Figure Description

[0040] Figure 1 This is a schematic diagram of the axially misaligned polygonal permanent magnet synchronous linear motor described in Embodiment 1. The armature winding adopts a hybrid method of ring winding and cross-tooth winding.

[0041] Figure 2 This is a schematic diagram of the initial position of the motor armature winding in Embodiment 1, where the armature winding is a single-layer winding. Figure 2 (a) Schematic diagram of the initial position and winding arrangement of the primary module to keep it stationary; Figure 2 (b) is a schematic diagram of the initial position of the axially misaligned primary module and the reconstructed winding arrangement;

[0042] Figure 3 This is a schematic diagram of the structure of an existing polygonal permanent magnet synchronous linear motor after the windings are connected.

[0043] Figure 4 This is a schematic diagram of the initial position and winding arrangement of the primary module of an existing polygonal permanent magnet synchronous linear motor;

[0044] Figure 5 This is a comparison chart of the back EMF performance of Example 1; in which... Figure 5 (a) is a waveform diagram of the no-load back EMF of an existing motor; Figure 5 (b) is the no-load back EMF waveform diagram of the motor of the present invention; Figure 5 (c) is a comparison chart of the FFT analysis of the no-load back EMF of phase A of the existing motor and the motor of the present invention;

[0045] Figure 6 This is a comparison chart of thrust fluctuation performance in Example 1; where... Figure 6 (a) is a comparison diagram of the no-load thrust of existing motors and the motor of the present invention; Figure 6 (b) is a comparison chart of the no-load thrust of the existing motor and the motor of the present invention using FFT analysis.

[0046] Figure 7 This is a comparison diagram of the load thrust of existing motors and the motor of this invention;

[0047] Figure 8 This is a schematic diagram of the axially misaligned polygonal permanent magnet synchronous linear motor described in Embodiment 2. The armature winding adopts a cross-tooth winding method, wherein... Figure 8 (a) is a three-dimensional structure diagram. Figure 8 (b) is a schematic diagram showing the misalignment of the four primary modules;

[0048] Figure 9 This is a schematic diagram of the axially misaligned polygonal permanent magnet synchronous linear motor described in Embodiment 3. The armature winding adopts a cross-tooth winding method, wherein... Figure 9 (a) is a three-dimensional structure diagram. Figure 9 (b) is a schematic diagram of the misalignment of the four primary modules. Detailed Implementation

[0049] 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.

[0050] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0051] 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.

[0052] Specific Implementation Method 1: The following is combined with... Figures 1 to 5 This embodiment describes an axially misaligned polygonal permanent magnet synchronous linear motor, including...

[0053] Four primary modules are arranged in a polygonal layout on the outside;

[0054] And a secondary module, located at the center of the polygon layout, is a cuboid frame structure with openings at both ends, and has the same air gap distance as all primary modules;

[0055] The secondary module includes a secondary core and permanent magnets. The secondary core is a cuboid frame structure with openings at both ends. The permanent magnets of the secondary module are arranged alternately along the N-S axis, and the circumferential magnetization direction is the same.

[0056] The secondary core can be made of either magnetic or non-magnetic materials.

[0057] When using magnetically conductive materials for the secondary core, silicon steel sheets, amorphous alloy materials, or soft magnetic composite materials can be selected.

[0058] When using non-magnetic materials for the secondary core, aluminum alloy or titanium alloy can be selected.

[0059] The armature windings of each phase under the four primary modules are connected in series or in parallel to form a phase winding, and the same phase is connected in series between the modules.

[0060] The four primary modules have the same axial length.

[0061] A primary module on either side of the motor is selected as the reference module. The initial positions of the remaining primary modules are offset axially by a distance ΔL from the reference module, forming an axial misalignment structure. The three ΔL values ​​of the motor may be equal or unequal, and the phase changes caused by the axial misalignment are offset by reconfiguring the windings. When two opposing modules have the same ΔL, they can counteract the normal force.

[0062] By matching different offset distances according to the composition and phase of the force at the motor end, the end force can be weakened and the thrust fluctuation can be reduced.

[0063] Because the armature winding is constrained by the slot potential star diagram, its adjustable range is limited. If the initial position of the primary module with phase A as the starting phase is 2kτ, and this primary module is the reference module, and the motor slot electrical angle is α = 360° × P / Z, taking phase A as the reference phase as an example, the adjustable range is that the phase A winding moves from the nth slot to the mth slot at the left end of the motor. Then the phase change range of the phase A winding is (mn) × α. To cancel the phase change, the selectable axial misalignment distance has the following four cases:

[0064] Case 1: When β = 2α or β = -2α, based on the principle that the phase of the reference phase A is unchanged at 2kτ, each phase winding is moved by two slots in sequence to offset the phase change caused by axial misalignment, so that the phase of the back electromotive force of A is still 2kτ.

[0065] In the formula:

[0066] β is the electrical angle corresponding to the axial misalignment distance ΔL;

[0067] k is an integer, k = 0, ±1, ±2;

[0068] τ is the electric angle of the electrode distance, τ = 180°;

[0069] α is the slot electrical angle of the motor, α=360°×P / Z, where P is the number of pole pairs and Z is the number of slots;

[0070] Case 2: When β≠±2α, the windings of the axially misaligned primary module are reconstructed based on the principle that the phase 2kτ of the reference phase A remains unchanged, and the initial position of the axially misaligned primary module is adjusted according to the following formula:

[0071] β=2kτ-(mn)×α

[0072] (mn) represents the number of slots moved by each phase winding during the reconstruction of phase A winding; n and m are the slot numbers before and after the reconstruction of phase A winding, respectively. The remaining phases are moved by (mn) slots in sequence to maintain the symmetry of the three-phase windings.

[0073] (mn)×α is the phase offset caused by the reconfiguration of phase A winding;

[0074] The remaining phases are adjusted sequentially according to the slot potential star diagram to make the three-phase windings symmetrical;

[0075] In this case, after axial misalignment, the change in electrical angle caused by the misalignment is offset by reconfiguring the winding. The phase of the motor winding does not change before and after axial misalignment, and the back EMF is an algebraic superposition relationship.

[0076] Case 3: When β≠±2α, the windings of the axially misaligned primary module are reconstructed based on the phase change of the reference phase A as (2k+1)τ, and the initial position of the axially misaligned primary module is adjusted according to the following formula:

[0077] β=(2k+1)τ-(mn)×α

[0078] The remaining phases are adjusted sequentially according to the slot potential star diagram to make the three-phase windings symmetrical;

[0079] In this case, axial misalignment and winding reconstruction will cause the winding phase to reverse. By changing the direction of the current entering and exiting the winding or by changing the polarity of the permanent magnet on this side, the phase of the motor winding before and after axial misalignment can be kept unchanged, and the back EMF is an algebraic superposition relationship.

[0080] Case 4: When β≠±2α, the windings of the axially misaligned primary module are reconstructed based on the principle that the phase change of the reference phase A is close to kτ, and the initial position of the axially misaligned primary module is adjusted according to the following formula:

[0081] β+(mn)×α≈2kτ or (2k+1)τ.

[0082] In this case, there will be a certain phase difference between the phases of the motor windings before and after axial misalignment. However, the axial misalignment distance of each primary module can be flexibly adjusted according to the composition and phase of the motor end force to weaken specific harmonics, thereby maximizing the reduction of end force and reducing thrust fluctuation.

[0083] Regarding the winding polarity or permanent magnet polarity limitations for four scenarios:

[0084] In cases one and two, the winding phase and current direction of the misaligned module remain unchanged; in case three, the polarity of the secondary permanent magnet corresponding to the misaligned module is reversed, the winding current direction is reversed, or the winding is reversed; in case four, when the relationship β+(mn)×α≈2kτ is satisfied, the winding phase and current direction of the misaligned module remain unchanged; when the relationship β+(mn)×α≈(2k+1)τ is satisfied, the polarity of the secondary permanent magnet corresponding to the misaligned module is reversed, the winding current direction is reversed, or the winding is reversed.

[0085] Regarding the limitations on winding methods in four scenarios:

[0086] The armature winding in the primary module is a single-layer winding or a double-layer winding, using a cross-tooth winding method or a combination of cross-tooth winding and ring winding.

[0087] Case 1: The windings of the two primary modules are arranged and positioned the same, and the upper and lower and left and right primary modules are staggered by a fixed electrical angle of 2α or -2α. The windings adopt a combination of cross-tooth winding and ring winding. The windings of the end extension area formed by axial misalignment adopt cross-tooth winding, and the overlapping area of ​​the four primary modules adopts ring winding. Cases 2, 3, and 4: The windings of the four primary modules uniformly adopt cross-tooth winding.

[0088] The core of the primary module is made of silicon steel sheet, amorphous alloy material or soft magnetic composite material.

[0089] In the first, second, and third cases, there is no phase difference in the back EMF between the axially misaligned primary modules, but there is a phase difference in the end force, which can weaken the end force and reduce thrust fluctuation. However, the adjustable axial misalignment distance is relatively limited. In the fourth case, there is a certain phase difference in the back EMF between the axially misaligned primary modules, which will have a slight impact on the back EMF and output thrust. However, the axial misalignment distance of each primary module can be flexibly adjusted according to the composition and phase of the motor end force to obtain a smaller thrust fluctuation.

[0090] The following specific examples illustrate this:

[0091] The axially staggered polygonal permanent magnet synchronous linear motor comprises four primary modules, which are fixed inside the housing and maintain a fixed air gap with the secondary modules. Each secondary module includes a secondary core and permanent magnets. The secondary core is a cuboid frame structure open at both ends. The permanent magnets in the secondary modules are arranged alternately along the N-S axis, with the same circumferential magnetization direction. The permanent magnets are located on the sides of the secondary module facing the primary modules. The modules are connected by mechanical and electrical connectors, exhibiting high interchangeability and compatibility.

[0092] The axial offset distance of the primary modules and the reconfiguration of the winding arrangement are the key points of this invention. Existing polygonal permanent magnet synchronous linear motors use ring-shaped armature windings, and the initial position and winding arrangement of the primary modules are identical. The motor forms a symmetrical structure along the circumference, resulting in an algebraic superposition relationship between the total end force of the motor and the resultant end force of each primary module. Consequently, the motor suffers from large end forces and high thrust fluctuations. To address this issue, this invention's axially offset polygonal permanent magnet synchronous linear motor alters the phase of the end forces on each side by axially offsetting and reconfiguring the winding arrangement, thus weakening the resultant end force and reducing the overall thrust fluctuation of the motor.

[0093] The armature windings under each phase of the four primary modules are connected in series or in parallel to form a phase winding. The same phase is connected in series between the modules. The primary unit on any side of the motor is selected as the reference module, and the initial positions of the other primary units are offset axially by a distance ΔL based on it, forming an axially offset structure. Each ΔL can be the same or different. When two primary modules opposite each other have the same ΔL, it can play a role in canceling the normal force.

[0094] Example 1, see Figures 1 to 7 The motor has a single-layer winding, three-phase, 12-slot, 10-pole configuration, with P=5 and Z=12. The armature winding employs a combination of toroidal and cross-tooth winding. Two circumferentially adjacent primary modules are axially misaligned and have different armature winding arrangements, while the initial positions of two opposite primary modules are the same as their armature winding arrangements.

[0095] In this example, the slot angle is α = 360° × P / Z = 150°. Using the upper primary module as the reference module, its initial position is 2kτ. The initial position and winding arrangement are as follows: Figure 2 As shown in (a), the electrical angle corresponding to the misalignment distance ΔL in this example is -2α.

[0096] This example uses the first scenario described above. The electrical angle corresponding to the misalignment distance ΔL is -2α. By moving the A-phase winding from slot 1 to slot 3, the phase change is made to 2α, thus offsetting the effect of axial misalignment on the phase. After the A-phase winding is moved, the remaining phases are adjusted sequentially according to the slot potential star diagram to make the three-phase windings symmetrical. The initial position of the axially misaligned primary module and the reconstructed winding arrangement are as follows: Figure 2 As shown in (b).

[0097] The permanent magnets of the secondary module are arranged alternately in the N-S direction along the axial direction, and the permanent magnets are magnetized in the same direction along the circumferential direction.

[0098] The performance of the axially misaligned polygonal permanent magnet synchronous linear motor in this example will be described below, taking a single-layer winding, three-phase 12-slot 10-pole motor as an example.

[0099] Figure 5 (a) Provide the no-load back EMF waveform of the existing motor. Figure 5 (b) Provides the no-load back EMF waveform diagram of the motor of the present invention, combined with... Figure 5 (c) It can be seen that the no-load back EMF of the motor of the present invention is the same as that of the existing motor, and the axial misalignment structure does not affect the magnitude of the no-load back EMF.

[0100] Figure 6 (a) is a comparison of the no-load thrust of the existing motor and the motor of the present invention. It can be seen that the thrust fluctuation of the motor of the present invention under no-load conditions is significantly reduced compared with the thrust fluctuation of the existing motor. In this example, the peak value of the thrust fluctuation decreased from 1208.76N to 675.12N, a decrease of 44.15%, which is beneficial to improving the stability of the motor system.

[0101] Figure 6 (b) is a comparison chart of the FFT analysis of the no-load thrust of the existing motor and the motor of the present invention. It can be seen that the thrust fluctuation of the existing motor under no-load conditions mainly consists of the first and second harmonics, while the axial misalignment of the motor of the present invention weakens these harmonics, with a greater weakening of the first harmonic and a significant reduction in thrust fluctuation.

[0102] Figure 7 This is a comparison chart of the load thrust of the motor of the present invention and existing motors. It can be seen that the thrust fluctuation of the motor of the present invention under load is significantly reduced compared with that of existing motors, which is beneficial to improving the stability of the motor system.

[0103] Example 2, see also Figure 8 The three-dimensional structural diagram of the motor in this example is shown below. Figure 8As shown, in this example, the armature winding uses only a cross-tooth winding method. Taking the upper primary module as a reference, the right, lower, and left primary modules are offset from the reference primary module by a certain distance, namely τ / 4, 2τ / 4, and 3τ / 4, respectively. After the offset, the winding is rearranged using the winding reconstruction method described above. In this scheme, except for the reference primary module, the other three primary modules are all offset from the reference module by different distances. The advantage of this scheme is that each primary module can flexibly adjust the offset distance according to the composition of thrust fluctuation, weakening specific harmonics and reducing the overall thrust fluctuation of the motor.

[0104] Example 3, see Figure 9 The three-dimensional structural diagram of the motor in this example is shown below. Figure 9 As shown, the armature winding in this example uses only a cross-tooth winding method. The upper and lower primary unit windings are arranged and positioned identically. Using the upper and lower primary units as references, the left and right primary units are offset by a distance of ±τ2 / 9. After the offset, the windings are rearranged using the winding reconstruction method described above. In this scheme, except for the two upper and lower reference primary modules, the other two primary modules are offset relative to the reference modules by different distances. The advantage of this example is that the normal force between the upper and lower primary units is balanced, and the offset of the left and right modules reduces the overall thrust fluctuation of the motor.

[0105] 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. An axial-displacement polygon permanent magnet synchronous linear motor, characterized by, include: Four primary modules are arranged on the outside in a polygonal layout; And a secondary module, located at the center of the polygon layout, is a cuboid frame structure with openings at both ends, and has the same air gap distance as all primary modules; Select any primary module on one side of the motor as the reference module, and set the initial positions of the other primary modules to be offset axially by a distance ΔL based on the reference module, forming an axial misalignment structure; the three ΔL values ​​of the motor may be equal or unequal, and the phase change caused by the axial misalignment is offset by reconfiguring the windings. The secondary module includes a secondary core and permanent magnets. The secondary core is a cuboid frame structure with openings at both ends. The permanent magnets of the secondary module are arranged alternately along the N-S axis and have the same circumferential magnetization direction. The axial misalignment distance ΔL satisfies one of the following relationships: Scenario 1: or At that time, the phase of reference phase A is used. Assuming no change, each phase winding is shifted sequentially by two slots to offset the phase change caused by axial misalignment, ensuring that the phase of the back potential at phase A remains constant. ; In the formula: The electrical angle corresponding to the axial misalignment distance ΔL; For integers, k = 0, ±1, ±2; The electrode distance is the electrical angle. =180°; For the motor slot electrical angle, , For extreme logarithms, Number of slots; Scenario 2: At that time, the phase of reference phase A is used. The windings of the remaining axially misaligned primary modules are reconstructed, and the initial positions of the axially misaligned primary modules are adjusted according to the following formula: In the formula: This represents the number of slots that each phase winding moves during the reconfiguration of phase A winding; , These are the slot numbers before and after the reconstruction of phase A winding, and the remaining phases are moved sequentially. The position of each slot is to maintain the symmetry of the three-phase windings; This represents the phase offset caused by the reconfiguration of phase A winding; The remaining phases are adjusted sequentially according to the slot potential star diagram to make the three-phase windings symmetrical; Scenario 3: At that time, the phase change of the reference phase A is taken as To achieve this, the windings of the axially misaligned primary module are reconstructed, and the initial position of the axially misaligned primary module is adjusted according to the following formula: The remaining phases are adjusted sequentially according to the slot potential star diagram to make the three-phase windings symmetrical; Scenario 4: At that time, the phase change of the reference phase A is close to To achieve this, the windings of the axially misaligned primary module are reconstructed, and the initial position of the axially misaligned primary module is adjusted according to the following formula: or .

2. The axially offset polygonal permanent magnet synchronous linear motor according to claim 1, characterized in that, Case 1 and Case 2: The winding method and current direction of the misaligned module remain unchanged; Case 3: The polarity of the secondary permanent magnet corresponding to the misaligned module is reversed, the winding current direction is changed, or the winding is reversed; Case 4: When the following conditions are met... When the relationship is satisfied, the winding method and current direction of the misaligned module remain unchanged; when the relationship is satisfied... When the relationship is expressed, the polarity of the secondary permanent magnet corresponding to the misaligned module is reversed, the winding current direction is changed, or the winding is reversed.

3. The axially offset polygonal permanent magnet synchronous linear motor according to claim 2, characterized in that, The armature winding in the primary module is a single-layer winding or a double-layer winding, using a cross-tooth winding method or a combination of cross-tooth winding and ring winding.

4. The axially offset polygonal permanent magnet synchronous linear motor according to claim 3, characterized in that, Case 1: The windings of the two primary modules are arranged and positioned the same, and the upper and lower and left and right primary modules are staggered by a fixed electrical angle of 2α or -2α. The windings adopt a combination of cross-tooth winding and ring winding. The windings of the end extension area formed by axial misalignment adopt cross-tooth winding, and the overlapping area of ​​the four primary modules adopts ring winding. Cases 2, 3, and 4: The windings of the four primary modules uniformly adopt cross-tooth winding.

5. The axially offset polygonal permanent magnet synchronous linear motor according to claim 1, characterized in that, The core of the primary module is made of silicon steel sheet, amorphous alloy material or soft magnetic composite material.

6. The axially misaligned polygonal permanent magnet synchronous linear motor according to claim 1, characterized in that, The secondary core can be made of either magnetic or non-magnetic materials.

7. The axially misaligned polygonal permanent magnet synchronous linear motor according to claim 6, characterized in that, When using magnetically conductive materials for the secondary core, silicon steel sheets, amorphous alloy materials, or soft magnetic composite materials can be selected.

8. The axially misaligned polygonal permanent magnet synchronous linear motor according to claim 6, characterized in that, When using non-magnetic materials for the secondary core, aluminum alloy or titanium alloy can be selected.

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