A moving magnet linear motor and a design method thereof

Abstract

The application discloses a moving-magnet linear motor and a design method thereof, and the motor comprises a secondary mover and two primary stators which are symmetrically arranged above and below, or the primary stators are located between an upper mover and a lower mover which are symmetrically arranged above and below; the primary stator comprises a rhombic winding and a PCB connecting plate, the rhombic winding is composed of multiple groups of unit rhombic windings, each group of unit rhombic windings is continuously wound by conductive wires to form a closed rhombus, four sides are smoothly and obliquely connected to make all the sides effective magnetic field action sides, a short diagonal line is arranged along a movement direction of the linear motor, a long diagonal line is arranged along a transverse direction of the linear motor, and all the unit rhombic windings are connected by the PCB connecting plate; and the secondary mover is a Halbach array. The application improves the slot fill factor of the motor winding and the thrust density of the motor, and reduces the thrust fluctuation of the motor.

Description

Technical Field

[0001] This invention belongs to the field of electromagnetic transmission technology, specifically relating to a moving magnet linear motor and its design method. Background Technology

[0002] As a core device of direct-drive electromagnetic transmission, linear motors are widely used in high-end CNC machine tools, semiconductor equipment, precision logistics transmission, rail transportation and other fields. At the same time, there are more and more ultra-precision workpiece stages that use linear motors as drive devices. In order to meet the working conditions of the workpiece stages, new requirements have been put forward for linear motors to have smaller thrust fluctuations and smoother motion.

[0003] Common methods to reduce thrust fluctuations include: using skewed poles and slots; disrupting the periodic superposition of cogging thrust to cancel out harmonics; employing unequal tooth width or pitch designs; optimizing cogging openings; or topology optimization of the permanent magnet structure, such as tile-type or segmented permanent magnets. However, these methods have limited effectiveness. Furthermore, the mainstream windings used in linear motors are currently rectangular. While the winding technology for this type of winding is mature, its compatibility with the linear traveling wave magnetic field distribution and linear thrust output of linear motors is inherently flawed. In high-precision, high-thrust-density, and low-pulsation high-end applications, this technological shortcoming is particularly pronounced.

[0004] Therefore, there is an urgent need for a new linear motor structure and design method that can overcome the above-mentioned defects. Summary of the Invention

[0005] To address the problems of large thrust fluctuations and low slot fill factor caused by poor compatibility between rectangular windings and traveling wave magnetic fields in existing technologies, this invention achieves synergistic optimization of high thrust density and low thrust fluctuation through a moving magnet linear motor and its design method.

[0006] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: An embodiment of the present invention provides a moving magnet linear motor, comprising: The motor includes a secondary mover and two primary stators symmetrically arranged vertically. The secondary mover is located between the two primary stators. The secondary mover includes an upper mover and a lower mover arranged symmetrically vertically. Alternatively, the motor includes a primary stator and a secondary mover. The secondary mover includes an upper mover and a lower mover arranged symmetrically vertically. The primary stator is located between the upper mover and the lower mover. The primary stator includes a rhombic winding and a PCB connecting board. The rhombic winding is composed of multiple sets of unit rhombic windings. Each set of unit rhombic windings is formed by continuously winding conductive wires to form a closed rhombus. The four sides of the closed rhombus are smoothly connected at oblique angles so that all four sides are effective magnetic field sides. The short diagonal of the unit rhombic winding is set along the direction of linear motor movement, and the long diagonal is set along the lateral direction of linear motor. All unit rhombic windings of the rhombic winding are connected by the PCB connecting board. The secondary mover is a Heilbeck array.

[0007] In a preferred embodiment, the four sides of the unit rhombic winding are of equal length; and / or the unit rhombic winding includes four sequentially smoothly connected first, second, third, and fourth sides, the first and second sides being located in the same first plane, the third and fourth sides being located in the same second plane, and there is a height difference between the first and second planes; and / or the short diagonals of adjacent unit rhombic windings are collinear.

[0008] In a preferred embodiment, in adjacent rhomboid windings of the rhomboid winding, the third and fourth sides of one rhomboid winding are vertically attached to the first and second sides of another rhomboid winding, forming a continuous winding array along the direction of linear motor movement; and / or, the first planes of all the rhomboid windings coincide and the second planes of all the rhomboid windings also coincide.

[0009] In a preferred embodiment, the PCB connecting board is arranged along the direction of linear motor movement and is located at the middle position of the rhombic winding.

[0010] In a preferred embodiment, both the upper mover and the lower mover include a main permanent magnet, a side permanent magnet, and an auxiliary permanent magnet. The auxiliary permanent magnet is located between the side permanent magnet and the main permanent magnet, or between two main permanent magnets. The magnetization direction of the main permanent magnet and the side permanent magnet is vertical. The magnetization direction of the side permanent magnet is vertical, and the magnetization direction of the auxiliary permanent magnet is horizontal. The side permanent magnet of the upper mover includes an upper left side permanent magnet and an upper right side permanent magnet, and the side permanent magnet of the lower mover includes a lower left side permanent magnet and a lower right side permanent magnet.

[0011] In a preferred embodiment, when the secondary mover is located between the two primary stators, the magnetization direction of the upper left permanent magnet and the upper right permanent magnet is downward and the magnetization direction of the lower left permanent magnet and the lower right permanent magnet is upward, or the magnetization direction of the upper left permanent magnet is downward to the right, the magnetization direction of the lower left permanent magnet is upward to the right, the magnetization direction of the upper right permanent magnet is downward to the left, and the magnetization direction of the lower right permanent magnet is upward to the left, thereby forming an inwardly cohesive Heilbeck array.

[0012] In a preferred embodiment, when the primary stator is located between the two secondary movers, the magnetization directions of the main permanent magnets and the side permanent magnets corresponding to the upper and lower positions of the upper and lower movers are consistent, and the magnetization direction of the auxiliary permanent magnets cooperates with the adjacent main permanent magnets and side permanent magnets to form a complete magnetic path.

[0013] In a preferred embodiment, the primary stator further includes a core back plate and a housing, the rhombic winding and the PCB connecting plate are fixed on the core back plate, and the rhombic winding, the PCB connecting plate and the core back plate are all fixed inside the housing; the secondary mover further includes a magnetic back plate, and the upper mover and the lower mover are both fixed on the magnetic back plate.

[0014] In a preferred embodiment, the motor pole slots are configured as two poles and six slots. In the formula, The pole distance of the main permanent magnet. It represents the distance between the long diagonals of two adjacent rhomboid windings.

[0015] On the other hand, one embodiment of the present invention provides a design method for a moving magnet linear motor, including: S1, according to the preset motor pole slots, arrange the secondary mover size and the spacing between the long diagonal of the adjacent two units of the primary stator rhombic winding; S2, obtain the output waveform of the rhombic winding of the upper and lower primary stators, and extract the amplitude and phase from the output waveform; S3. Based on the extracted amplitude and phase information, iteratively adjust the geometric parameters of the unit rhombic winding until the output waveforms of the upper and lower primary stators are superimposed and meet the conditions of equal amplitude and opposite phase.

[0016] Compared with existing technologies, the beneficial effects of this invention are as follows: The moving magnet linear motor and its design method provided by this invention, by adopting a unit rhomboid winding with smooth oblique transitions on four sides, eliminates the ineffective right-angle ends of traditional rectangular windings, making all four sides of the winding effective magnetic field sides, significantly improving slot fill factor and conductor utilization; at the same time, the rhomboid profile is precisely matched with the cutting direction of the traveling wave magnetic field of the linear motor, ensuring effective coupling throughout the entire process, reducing harmonic content and thrust fluctuations from the source. The secondary mover adopts a Heilbeck array structure, utilizing a specific combination of magnetization directions of the main permanent magnet, side permanent magnet, and auxiliary permanent magnet to achieve sinusoidal air gap magnetic field and single-sided magnetization effect, further improving thrust density. Especially in the configuration of a double-sided primary with a middle mover, by setting the side permanent magnets to be magnetized inwardly, the end leakage magnetic field effect of the short secondary mover is effectively suppressed, avoiding sudden rises and falls of the magnetic field at the ends, thus achieving extremely low thrust fluctuations while ensuring high thrust output, meeting the stringent requirements of high-end precision equipment for motion stability. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram (longitudinal section) of the linear motor structure of Embodiment 1 of the present invention; Figure 2 This is a schematic diagram (transverse section) of the linear motor structure of Embodiment 1 of the present invention; Figure 3 This is a schematic diagram of the linear motor structure of Embodiment 1 of the present invention (with the outer shell 115 removed); Figure 4 This is a top view schematic diagram of the rhomboid winding and secondary stator of Embodiment 1 of the present invention; Figure 5 This is a slanted view of the rhomboid winding in Embodiment 1 of the present invention; Figure 6 This is a cross-sectional schematic diagram of the intermediate moving part in Embodiment 1 of the present invention; Figure 7 This is a schematic diagram of the magnetic field lines at the end of a traditional magnet array; Figure 8 This is a schematic diagram of the magnetic field lines at the end of the magnet array in Embodiment 1 of the present invention; Figure 9 This is a schematic diagram of the three-phase winding star configuration of Embodiment 1 of the present invention; Figure 10This is a flowchart of the design method for a moving magnet linear motor according to Embodiment 2 of the present invention; Figure 11 This is a schematic diagram of another variant of Embodiment 1 of the present invention (intermediate primary double-sided mover); Figure 12 This is a schematic diagram of another variation (transverse section) of Embodiment 1 of the present invention; Figure 13 This is a schematic diagram of another variant of Embodiment 1 of the present invention (a two-sided mover Halbach array).

[0019] Reference numerals: 1. Primary stator; 11. Upper primary stator; 12. Lower primary stator; 111. Diamond winding; 112. Unit rhombic winding, 113, PCB connection board, 114, core back plate, 115, outer shell, 1121, first side, 1122, second side, 1123, third side, 1124, fourth side, 1125, acute angle, 1126, obtuse angle, 2, secondary mover, 21, main permanent magnet, 22, side permanent magnet, 23, auxiliary permanent magnet, 24, magnetic back plate, 221, upper left permanent magnet, 222, lower left permanent magnet, 223, upper right permanent magnet, 224, lower right permanent magnet. Detailed Implementation

[0020] The invention will be more fully understood through the following detailed description, which should be read in conjunction with the accompanying drawings. Detailed embodiments of the invention are disclosed herein; however, it should be understood that the disclosed embodiments are merely exemplary of the invention, which may be embodied in various forms. Therefore, the specific functional details disclosed herein should not be construed as limiting, but rather as the basis for the claims and as intended to teach those skilled in the art to employ the representative basis of the invention in different ways in any suitable detailed embodiment.

[0021] Example 1 Combination Figures 1-3 As shown, this embodiment provides a moving-magnet linear motor, which includes a secondary mover 2 and two symmetrically distributed primary stators 1 (defined as upper primary stator 11 and lower primary stator 12, respectively). The secondary mover 2 is located between the two primary stators 1. Specifically, this topology of bilateral primary stators sandwiching a middle mover can utilize the magnetic fields of both stators to form a symmetrical electromagnetic pull on the middle mover, effectively counteracting the normal force fluctuation caused by unilateral magnetic pull, thereby improving motion stability. It should be understood that although this embodiment uses bilateral stators sandwiching a middle mover as an example, in other embodiments, a configuration of a middle stator sandwiching bilateral movers can also be used, as long as the relative motion relationship between the primary and secondary stators is satisfied.

[0022] In this embodiment, the primary stator 1 specifically includes a rhombus winding 111, a PCB connecting board 113, a core back plate 114, and a housing 115. The rhombus winding 111 is composed of multiple sets of unit rhombus windings 112 with equal sides and adjustable diagonals. Each set of unit rhombus windings 112 is a closed electromagnetic winding formed by continuously winding multiple turns of conductive wire. The electromagnetic winding has a regular rhombus outline (i.e., the projection surface of the winding after winding is a standard rhombus). The four sides of the closed rhombus are smoothly connected at oblique angles, without right-angle winding structure, so that all four sides are effective magnetic field action sides.

[0023] Specifically, traditional rectangular windings have right-angled ends at the corners. The direction in which the conductor cuts the magnetic field lines is inconsistent with the direction of the traveling wave magnetic field, making these ineffective edges. This not only occupies space and reduces slot fill factor but also generates additional harmonic magnetic fields, causing thrust fluctuations. This embodiment eliminates rigid right angles through a smooth, beveled transition design on all four sides, ensuring that all four sides of the winding maintain a precise cutting angle match with the sinusoidal traveling wave magnetic field of the linear motor, participating in effective electromagnetic energy conversion throughout the entire process. For example, the smooth beveled transition can be a circular arc transition, an elliptical arc transition, or a curve transition fitted with multiple segments of broken lines, as long as the conductor direction is continuous and without abrupt inflection points. This design significantly improves the effective utilization rate of the conductors and reduces harmonic content at the source.

[0024] Combination Figures 3-5 As shown, the four sides of each unit rhombic winding 112 are of equal length. Specifically, the design of equal-length sides gives the windings a high degree of geometric symmetry, which is beneficial to the impedance balance and magnetomotive force waveform symmetry of the three-phase windings, and reduces even-order harmonics caused by winding asymmetry. Each unit rhombic winding 112 specifically includes four sequentially and smoothly connected sides: a first side 1121, a second side 1122, a third side 1123, and a fourth side 1124. The first side 1121 and the second side 1122 are located in the same first plane, and the third side 1123 and the fourth side 1124 are located in the same second plane. There is a height difference between the first plane and the second plane. In this embodiment, the first plane is slightly higher than the second plane. Specifically, this three-dimensional stacked structure is designed to accommodate the thickness of the conductor itself and avoid the risk of insulation wear or short circuits caused by adjacent sides crossing in the same plane. The size of the height difference is usually determined according to the conductor diameter and insulation layer thickness, for example, it can be 1 to 2 times the conductor diameter, to ensure electrical safety while minimizing the overall axial dimension of the winding.

[0025] Preferably, the two obtuse angles α of the unit rhombic winding 112 are arranged opposite each other in the direction of linear motor movement, and the two acute angles β are arranged opposite each other in the transverse direction of linear motor (perpendicular to the direction of linear motor movement). This angle design ensures that all four winding sides of the unit rhombic winding 112 are precisely matched with the cutting direction of the traveling wave magnetic field of the linear motor, guaranteeing effective coupling throughout the entire process. Furthermore, this angle design corresponds to setting the short diagonal of the unit rhombic winding 112 along the direction of linear motor movement and the long diagonal along the transverse direction of linear motor, adapting to the magnetic field extension characteristics of the linear motor.

[0026] Preferably, the short diagonals of multiple unit rhombic windings 112 are stacked one-sidedly along the direction of linear motor movement, and the short diagonals of adjacent unit rhombic windings are collinear. This ensures the consistency of the arrangement of all unit rhombic windings 112 along the direction of movement, making the synthesized magnetomotive force waveform smoother. Among adjacent unit rhombic windings 112, the third side 1123 and the fourth side 1124 of one unit rhombic winding 112 (such as the previous unit rhombic winding) are vertically attached to the first side 1121 and the second side 1122 of another unit rhombic winding 112 (such as the next unit rhombic winding), forming a continuous winding array along the direction of linear motor movement. Specifically, this close-fitting arrangement eliminates the waste of gaps between traditional windings and achieves an extremely high space filling rate. More preferably, the first planes of all unit rhombic windings 112 coincide, and the second planes of all unit rhombic windings 112 also coincide. This means that the entire rhombic winding array forms a neat double-layer planar structure in the axial direction, which not only greatly improves the filling rate of the linear motor winding, but also facilitates automated winding and assembly and ensures the uniformity of air gap magnetic resistance, avoiding local magnetic saturation or thrust pulsation caused by uneven winding height.

[0027] In addition, the two output terminals of each unit rhombic winding 112 are soldered to the PCB connection board 113, and all unit rhombic windings 112 of the rhombic winding 111 are connected by the PCB connection board 113. The circuit of the PCB connection board 113 is determined by the linear motor pole slot matching. In this embodiment, a symmetrical three-phase winding connection is formed, such as... Figures 7-9 As shown. Preferably, the PCB connecting board 113 is arranged along the direction of linear motor movement and is located in the middle of the rhombic winding. The connected primary stator rhombic winding 111 and PCB connecting board 113 are fixed to the core back plate 114, and all three are uniformly fixed inside the housing 115. Specifically, the core back plate 114 not only provides mechanical support but also serves as part of the magnetic circuit, providing a low magnetic reluctance loop and enhancing the air gap magnetic field strength. The PCB connecting board 113 integrates the electrical connection lines of the winding, replacing the traditional lead soldering method, improving the reliability and consistency of the connection, and saving lateral wiring space.

[0028] In this embodiment, the secondary mover 2 is a Halbach array. Specifically, the Halbach array is arranged with specific magnetization directions, which can enhance the magnetic field strength on the air gap side and weaken the magnetic field on the back plate side, thereby achieving a unilateral magnetic field focusing effect and sinusoidal distribution, further improving the thrust density of the motor and reducing cogging torque. In this embodiment, the secondary mover 2 specifically includes an upper mover and a lower mover arranged symmetrically, such as... Figure 6 As shown, both the upper and lower movers include a main permanent magnet 21, a side permanent magnet 22, and an auxiliary permanent magnet 23. The auxiliary permanent magnet 23 is located between the side permanent magnet 22 and the main permanent magnet 21, or between two main permanent magnets 21. The magnetization direction of the main permanent magnet 21 and the side permanent magnet 22 is vertical, while the magnetization direction of the auxiliary permanent magnet 23 is horizontal. Specifically, the main permanent magnet 21 provides the primary excitation magnetic field, and the auxiliary permanent magnet 23 guides the magnetic field lines through horizontal magnetization, working in conjunction with the vertically magnetized main permanent magnet 21 to form the unique magnetic focusing effect of the Hellbeck array. The side permanent magnets 22 of the upper mover specifically include an upper left side permanent magnet 221 and an upper right side permanent magnet 223, while the side permanent magnets 22 of the lower mover include a lower left side permanent magnet 222 and a lower right side permanent magnet 224.

[0029] In this embodiment, the magnetization direction of the edge permanent magnets 22 is inward. Specifically, the magnetization direction of the upper left edge permanent magnet 221 and the upper right edge permanent magnet 223 is downward, and the magnetization direction of the lower left edge permanent magnet 222 and the lower right edge permanent magnet 224 is upward, forming an inwardly converging Heilbeck array. This magnetization method can reduce the edge leakage magnetic effect of the short secondary mover and reduce the thrust fluctuation of the linear motor. Alternatively, preferably, in another alternative embodiment, the magnetization direction of the edge permanent magnets 22 can be deflected at a certain angle in the vertical direction. Specifically, for example, the magnetization direction of the upper left edge permanent magnet 221 is downward to the right, the magnetization direction of the lower left edge permanent magnet 222 is upward to the right, the magnetization direction of the upper right edge permanent magnet 223 is downward to the left, and the magnetization direction of the lower right edge permanent magnet 224 is upward to the left. For the short secondary mover, the end effect is the main cause of thrust fluctuation and magnetic field distortion. By setting the magnetization direction of the permanent magnets to be inward (i.e., tilted towards the central axis of the mover), the attenuation of the end magnetic field can be actively compensated, allowing the air gap magnetic field to maintain good sinusoidality and amplitude stability in the end region. For example, the tilt angle can be optimized between 0° and 45° according to the mover length and air gap size. A larger angle results in a stronger magnetizing effect but a weaker vertical component, requiring a trade-off based on actual operating conditions. This inward magnetization method effectively suppresses end magnetic leakage, avoids sudden rises and falls in the magnetic field at the end, achieves a smooth magnetic field transition, and significantly reduces the thrust fluctuation of the motor.

[0030] In addition, the secondary mover 2 also includes a magnetic back plate 24, on which both the upper and lower movers are fixed (e.g., glued). The magnetic back plate 24 provides a mounting reference and magnetic flux return path for the permanent magnets, ensuring the positional accuracy and magnetic circuit integrity of the magnet array.

[0031] In this embodiment, the motor pole slots are matched with two poles and six slots, which satisfies the following relationship: In the formula, The pole distance of the main permanent magnet 21 It represents the distance between the long diagonals of two adjacent rhomboid windings.

[0032] Specifically, the pole-slot configuration is a key parameter for suppressing specific harmonic thrust. By ensuring that the winding pitch and magnet pole pitch satisfy the aforementioned integer multiple relationship, specific harmonics in the induced electromotive force of the winding can be mutually canceled, thereby obtaining a more sinusoidal back electromotive force waveform and a smoother thrust output. It should be understood that although this embodiment uses a two-pole, six-slot configuration as an example, in other embodiments, other configurations can be selected based on thrust density and fluctuation suppression requirements. · = · The polar slot combination of the relationship, where, , These represent the number of poles and slots of the motor, respectively.

[0033] As an alternative implementation method of this embodiment, combined with Figures 11-13 As shown, the motor can also adopt a configuration where the intermediate primary stator 1 is located between the upper and lower movers of the secondary mover 2. In this case, the magnetization directions of the corresponding main permanent magnets 21 and the corresponding side permanent magnets 22 in the upper and lower movesrs are consistent, and the magnetization direction of the auxiliary permanent magnet 23, together with the adjacent main permanent magnets 21 and side permanent magnets 22, forms a complete magnetic path. After all permanent magnets are arranged in the correct order, they are pasted on the magnetic back plate 24.

[0034] Specifically, unlike the aforementioned configuration with a double-sided stator clamping a middle mover, when the stator is in the middle, the magnetic fields of the movers on the upper and lower sides need to pass through the middle stator to form a closed loop. Therefore, the magnetization directions of the magnets at corresponding positions on the upper and lower sides should be consistent (e.g., both with the N pole facing inward or both with the S pole facing inward), rather than opposite. The advantage of this variant is that it uses fewer windings, resulting in less motor loss; and the stator windings are concentrated in the middle, providing better heat dissipation and a lighter mover, making it suitable for high-speed applications sensitive to mover mass. In this variant, the structure of the rhombic winding 111, the connection method of the PCB connecting board 113, and the arrangement rules of the unit windings are the same as in the aforementioned embodiment, and will not be repeated here. In this embodiment, the PCB connecting board 113 is also located in the middle of the rhombic winding, ensuring that the distance between the upper and lower sides of the rhombic winding and the inner side of the double-sided mover is consistent. It should be understood that regardless of the topology configuration used, as long as the rhombic winding structure and the corresponding Heilbeck array described in this invention are used, they all fall within the protection scope of this invention. In addition to the two linear motor structures with short secondary and long primary rhombic windings mentioned above, a linear motor structure with long secondary and short primary rhombic windings can also be developed.

[0035] Example 2 like Figure 10 As shown, this embodiment provides a design method for a moving-magnet linear motor. This method is used for parametric design and performance optimization of the double-sided rhombic winding Halbach array moving-magnet linear motor in the aforementioned embodiment, to achieve a synergistic improvement in low thrust fluctuation and high thrust density. The method includes the following steps: Step S1: Arrange the secondary mover size and the distance between the long diagonal of the adjacent two units of the primary stator rhombic winding according to the preset motor pole slot arrangement.

[0036] Specifically, this step is a fundamental constraint step in establishing the motor's geometric model. Designers first determine the number of poles of the motor based on application requirements. And number of slots For example, in this embodiment, a two-pole, six-slot fit is preferred. Based on the pole-slot fit relationship... From this, the key dimension ratio between the primary stator 1 and the secondary mover 2 can be deduced. In the formula, The pole pitch of the main permanent magnet 21 is the distance between the center lines of two adjacent main permanent magnets 21. The spacing between the long diagonals of two adjacent rhombic windings 112 represents the spatial period of the winding. The initial geometric constraints determined by this formula ensure the synchronization of the fundamental magnetomotive force of the windings with the fundamental air gap magnetic field in terms of spatial layout, laying a structural foundation for subsequent suppression of specific harmonics. It should be understood that although this embodiment uses a two-pole, six-slot configuration as an example, in other embodiments, other pole-slot combinations that satisfy the above relationship can be selected based on the specific indicators of thrust density and wave suppression, and adjustments can be made accordingly. and The value.

[0037] Step S2: Obtain the output waveform of the rhombic winding of the upper and lower primary stators, and extract the amplitude and phase from the output waveform.

[0038] Specifically, this step is a crucial step in evaluating the electromagnetic performance of the initial design. Obtaining the output waveform can be achieved through finite element simulation or electromagnetic analytical calculation. In finite element simulation, a two-dimensional or three-dimensional electromagnetic field model is constructed, including the double-sided rhomboid winding and the central Halbach array as shown in Example 1. Boundary conditions for winding excitation current and mover motion are set, and the thrust waveform or back EMF waveform, varying with time or position, is obtained. In analytical calculation, the waveform is derived based on winding function theory and the air gap magnetic field distribution formula. Specific methods for extracting amplitude and phase include performing a Fast Fourier Transform (FFT) on the acquired discrete waveform data to separate the amplitude and phase information of the fundamental wave and major harmonic components; or using the least squares method to fit a sinusoidal fundamental wave to the waveform, directly obtaining the amplitude and phase of the fitting parameters. This step transforms the abstract electromagnetic field distribution into quantifiable signal characteristics, providing precise data support for subsequent targeted optimization.

[0039] After step S2, step S3 is also included, which iteratively adjusts the geometric parameters of the unit rhombic winding 112 based on the extracted amplitude and phase information until the output waveforms of the upper and lower primary stators are superimposed and meet the conditions of equal amplitude and opposite phase.

[0040] Specifically, this is the core closed-loop optimization step in achieving low thrust fluctuation in this design method. Since the primary stators on both sides are symmetrically distributed, ideally, the thrust fluctuation components should cancel each other out. However, due to factors such as manufacturing errors, end effects, and magnetic field nonlinearity, the actual waveform often deviates. This step addresses this by changing the diagonal angle (i.e., the obtuse angle) corresponding to the long diagonal of the rhombic winding. The system actively adjusts the effective length distribution of the winding conductors cutting magnetic field lines, thereby changing the content and phase of each harmonic in the induced electromotive force. When specific harmonics (such as the main harmonics causing thrust fluctuations) in the adjusted upper and lower winding output waveforms satisfy equal amplitude and opposite phase, these harmonic components will cancel each other out in the combined thrust, thus significantly reducing the thrust fluctuation of the motor. For example, if simulations find that the third harmonic is the main cause of thrust pulsation, then by finely adjusting the obtuse angle... The magnitude of the value changes the distribution factor of the third harmonic in the winding coefficient until the third harmonic thrust components of the upper and lower stators are completely canceled out. This parameter optimization method based on the waveform superposition principle breaks through the limitations of traditional passive means such as skewed poles or skewed slots to suppress fluctuations, and achieves the technical effect of actively eliminating harmonics at the winding topology level.

[0041] After waveform optimization, further multi-objective joint optimization can be performed on permanent magnet size, coil wire diameter and other mechanical structure dimensions to finally obtain the optimal parameter combination that balances high thrust density and low thrust fluctuation.

[0042] The advantages of this invention are as follows: The moving magnet linear motor and its design method provided by this invention, by adopting a unit rhomboid winding with smooth oblique transitions on all four sides, eliminates the ineffective right-angle ends of the traditional rectangular winding, making all four sides of the winding effective magnetic field sides, significantly improving slot fill factor and conductor utilization. Simultaneously, the rhomboid profile precisely matches the cutting direction of the linear motor's traveling wave magnetic field, ensuring effective coupling throughout the entire process and reducing harmonic content and thrust fluctuations at the source. The secondary mover adopts a Heilbeck array structure, utilizing a specific combination of magnetization directions of the main permanent magnet, side permanent magnets, and auxiliary permanent magnets to achieve sinusoidal air gap magnetic field and single-sided magnetization effect, further improving thrust density. Especially in the configuration of a double-sided primary with a middle mover, by setting the side permanent magnets to be magnetized inwardly, the end leakage magnetic field effect of the short secondary mover is effectively suppressed, avoiding sudden rises and falls in the magnetic field at the ends. This ensures high thrust output while achieving extremely low thrust fluctuations, meeting the stringent requirements of high-end precision equipment for motion stability.

[0043] Although the invention has been described with reference to illustrative embodiments, those skilled in the art will understand that various other changes, omissions, and / or additions can be made without departing from the spirit and scope of the invention, and that elements of the described embodiments can be substituted with substantially equivalents. Furthermore, many modifications can be made without departing from the scope of the invention to adapt particular situations or materials to the teachings of the invention. Therefore, this document is not intended to limit the invention to the specific embodiments disclosed for carrying out the invention, but rather to include all embodiments falling within the scope of the appended claims.

Claims

1. A moving magnet linear motor, characterized in that, The motor includes a secondary mover and two primary stators symmetrically arranged vertically. The secondary mover is located between the two primary stators. The secondary mover includes an upper mover and a lower mover arranged symmetrically vertically. Alternatively, the motor includes a primary stator and a secondary mover. The secondary mover includes an upper mover and a lower mover arranged symmetrically vertically. The primary stator is located between the upper mover and the lower mover. The primary stator includes a rhombic winding and a PCB connecting board. The rhombic winding is composed of multiple sets of unit rhombic windings. Each set of unit rhombic windings is formed by continuously winding conductive wires to form a closed rhombus. The four sides of the closed rhombus are smoothly connected at oblique angles so that all four sides are effective magnetic field sides. The short diagonal of the unit rhombic winding is set along the direction of linear motor movement, and the long diagonal is set along the lateral direction of linear motor. All unit rhombic windings of the rhombic winding are connected by the PCB connecting board. The secondary mover is a Heilbeck array.

2. The moving magnet linear motor according to claim 1, characterized in that: The four sides of the unit rhombic winding are of equal length; and / or the unit rhombic winding includes four sequentially smoothly connected first, second, third and fourth sides, the first and second sides are located in the same first plane, the third and fourth sides are located in the same second plane, and there is a height difference between the first plane and the second plane; and / or the short diagonals of adjacent unit rhombic windings are collinear.

3. A moving magnet linear motor according to claim 2, characterized in that: In adjacent rhombic windings of the rhombic winding, the third and fourth sides of one rhombic winding are vertically attached to the first and second sides of another rhombic winding, forming a continuous winding array along the direction of linear motor movement; and / or, the first planes of all rhombic windings coincide and the second planes of all rhombic windings also coincide.

4. A moving magnet linear motor according to claim 1, characterized in that: The PCB connecting board is arranged along the direction of linear motor movement and is located in the middle of the diamond winding.

5. A moving magnet linear motor according to any one of claims 1 to 4, characterized in that: Both the upper and lower actuators include a main permanent magnet, a side permanent magnet, and an auxiliary permanent magnet. The auxiliary permanent magnet is located between the side permanent magnet and the main permanent magnet, or between two main permanent magnets. The magnetization direction of the main permanent magnet and the side permanent magnet is vertical. The magnetization direction of the side permanent magnet is vertical, and the magnetization direction of the auxiliary permanent magnet is horizontal. The side permanent magnet of the upper actuator includes an upper left side permanent magnet and an upper right side permanent magnet, and the side permanent magnet of the lower actuator includes a lower left side permanent magnet and a lower right side permanent magnet.

6. A moving magnet linear motor according to claim 5, characterized in that: When the secondary mover is located between the two primary stators, the magnetization direction of the upper left permanent magnet and the upper right permanent magnet is downward and the magnetization direction of the lower left permanent magnet and the lower right permanent magnet is upward, or the magnetization direction of the upper left permanent magnet is downward to the right, the magnetization direction of the lower left permanent magnet is upward to the right, the magnetization direction of the upper right permanent magnet is downward to the left, and the magnetization direction of the lower right permanent magnet is upward to the left, thereby forming an inwardly cohesive Heilbeck array.

7. A moving magnet linear motor according to claim 5, characterized in that: When the primary stator is located between the two secondary movers, the magnetization directions of the main permanent magnets and the side permanent magnets corresponding to the upper and lower positions in the upper and lower movers are consistent, and the magnetization direction of the auxiliary permanent magnets cooperates with the adjacent main permanent magnets and side permanent magnets to form a complete magnetic path.

8. A moving magnet linear motor according to claim 1, characterized in that: The primary stator also includes a core back plate and a housing. The rhombic winding and the PCB connecting plate are fixed on the core back plate, and the rhombic winding, the PCB connecting plate and the core back plate are all fixed inside the housing. The secondary mover also includes a magnetic back plate, and the upper mover and the lower mover are both fixed on the magnetic back plate.

9. A moving magnet linear motor according to claim 5, characterized in that: The motor pole slots are configured as two poles and six slots. = In the formula, The pole distance of the main permanent magnet. It represents the distance between the long diagonals of two adjacent rhomboid windings.

10. A design method for a moving magnet linear motor according to any one of claims 1 to 9, characterized in that, The method includes: S1, according to the preset motor pole slots, arrange the secondary mover size and the spacing between the long diagonal of the adjacent two units of the primary stator rhombic winding; S2, obtain the output waveform of the rhombic winding of the upper and lower primary stators, and extract the amplitude and phase from the output waveform; S3. Based on the extracted amplitude and phase information, iteratively adjust the geometric parameters of the unit rhombic winding until the output waveforms of the upper and lower primary stators are superimposed and meet the conditions of equal amplitude and opposite phase.

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