Magnetic levitation planar motor and control method

Abstract

The application discloses a magnetic suspension plane motor and a control method, and relates to the field of motors.The magnetic suspension plane motor comprises a stator and a mover.The stator comprises, from bottom to top, a base, a Hall sensor array, a printed circuit board coil unit and a pressing plate.The printed circuit board coil unit is composed of multiple layers of printed circuit boards which are vertically stacked.The printed circuit board comprises multiple groups of coils and vias, and the coils on each layer of the printed circuit board are connected in series through the vias.The mover is located above the stator, and the mover comprises a two-dimensional Halbach permanent magnet array.The application can solve the problems of disordered wiring and low integration.

Description

Technical Field

[0001] This application relates to the field of electric motors, and in particular to a magnetically levitated planar motor and its control method. Background Technology

[0002] With the development of high-end fields such as semiconductor manufacturing and ultra-precision machining, stringent requirements are being placed on the positioning accuracy, multi-degree-of-freedom coordination, and dynamic response of motion actuators. Traditional mechanical transmission platforms, due to issues such as friction and wear, and backlash, are unable to meet nanometer-level positioning requirements. Magnetic levitation planar motors, with their advantages of contactless drive and zero friction, have become a key solution. Currently, magnetic levitation planar motors are mainly divided into two types: moving-coil and moving-magnet. The core structure mostly adopts a combination of Halbach permanent magnet arrays and planar coils. Although they partially achieve six-degree-of-freedom control, they suffer from problems such as poor coil scalability and insufficient heat dissipation efficiency.

[0003] Currently, the stator coil units of commonly used magnetic levitation planar motors on the market typically employ enameled coils, flexible circuit boards, or traditional rigid circuit boards. Among these, enameled coils have low winding arrangement precision, easily generating significant thrust pulsation (force ripple); moreover, the end wiring is messy, occupying a huge amount of space, which not only leads to large electromagnetic coupling interference but also results in extremely poor heat dissipation efficiency, hindering the miniaturization and high integration of the motor. Summary of the Invention

[0004] The purpose of this application is to provide a magnetic levitation planar motor and its control method, which is conducive to miniaturization and integration.

[0005] To achieve the above objectives, this application provides the following solution: In a first aspect, this application provides a magnetic levitation planar motor, comprising: a stator and a mover; the stator includes a base, a Hall sensor array, a printed circuit board coil unit, and a pressure plate connected sequentially from bottom to top; the printed circuit board coil unit is composed of multiple layers of printed circuit boards stacked perpendicularly to each other, each layer of printed circuit board including multiple sets of coils and vias, and the coils on each layer of printed circuit board are connected in series through the vias; the mover is located above the stator, and the mover includes a two-dimensional Heilbeck permanent magnet array.

[0006] In one embodiment, each coil group on the printed circuit board includes four forward conductors and four reverse conductors, with each pair of forward and reverse conductors forming a four-phase coil. The width of each coil group is equal to the electromagnetic period of the permanent magnet, and the spatial distance between the forward and reverse conductors of the same phase is [missing information]. One permanent magnet electromagnetic cycle.

[0007] In one embodiment, the coils between each layer of printed circuit boards adopt a three-dimensional series architecture that combines in-plane end folding and interlayer vertical descent.

[0008] In one embodiment, the printed circuit board coil unit adopts a method in which the X-direction and Y-direction windings are arranged alternately and orthogonally layer by layer.

[0009] In one embodiment, the mover further includes a mover array frame, in which a groove is provided, and the two-dimensional Heilbeck permanent magnet array is installed in the groove.

[0010] In one embodiment, the two-dimensional Heilbeck permanent magnet array is bonded to the groove using polyurethane methacrylate adhesive.

[0011] In one embodiment, the base, Hall sensor array, printed circuit board coil unit, and pressure plate are fixed by non-magnetic screws.

[0012] In one embodiment, the two-dimensional Heilbeck permanent magnet array includes a plurality of Heilbeck permanent magnet blocks.

[0013] In one embodiment, the via is a rounded rectangular slot.

[0014] Secondly, this application provides a control method for implementing the above-mentioned magnetic levitation planar motor, comprising: Based on the Lorentz force principle, an electromagnetic analytical model is established to describe the mapping relationship between coil current and electromagnetic force or torque.

[0015] Construct the force-current Jacobian transformation matrix for the real-time pose of the six-DOF mover.

[0016] Based on the outer-loop nonlinear model predictive controller, the globally optimal six-degree-of-freedom force or torque command is calculated according to the deviation between the input reference trajectory and the real-time pose feedback from the Hall sensor array, while satisfying the physical constraints of the motor.

[0017] The inner loop responds to the globally optimal six-degree-of-freedom force or torque command. Using the Jacobian transformation matrix updated in real time with the pose, the six-degree-of-freedom force or torque command issued by the outer loop is decoupled into independent current commands for each phase coil through matrix inverse operation.

[0018] Based on the independent current commands of each phase coil, dynamic commutation and current distribution are performed through a current driver, enabling the mover to obtain precise electromagnetic force or torque, and realizing the control of the mover's six degrees of freedom motion.

[0019] According to the specific embodiments provided in this application, the following technical effects are disclosed: This application provides a magnetic levitation planar motor and its control method. The stator of the magnetic levitation planar motor includes a base, a Hall sensor array, a printed circuit board coil unit, and a pressure plate connected sequentially from bottom to top. The mover is located above the stator. The printed circuit board coil unit is composed of multiple layers of printed circuit boards stacked perpendicularly to each other. Through the stacking structure, the symmetry of the coil layout and the magnetic field coupling efficiency are significantly improved, and edge effects and stray force interference are further suppressed. Each layer of printed circuit board includes multiple sets of coils and vias. The coils on each layer of printed circuit board are connected in series through the vias. By etching multiple sets of coils on the circuit board, a higher current density is achieved, thereby obtaining a greater output force. Under the same current, the force output is greater and the heat generation is lower. The coils on each layer of printed circuit board are connected in series through the vias, realizing high-density multi-layer seamless series connection of high-current coils, which can solve the problems of messy wiring and low integration. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the structure of a magnetic levitation planar motor according to one embodiment of this application.

[0022] Figure 2 This is a front view of a printed circuit board coil unit provided in an embodiment of this application.

[0023] Figure 3 This is a schematic diagram of the back structure of a printed circuit board coil unit provided in an embodiment of this application.

[0024] Figure 4 This is a schematic diagram of the connection method of eight wires within a polar distance provided in an embodiment of this application.

[0025] Figure 5 This is a top view schematic diagram of a Heilbeck permanent magnet array provided in an embodiment of this application.

[0026] Figure 6 This is a side view of a Heilbeck permanent magnet array provided in an embodiment of this application.

[0027] Figure 7 This is a hardware block diagram of a magnetic levitation planar motor provided in one embodiment of this application.

[0028] Figure 8 This is a control flowchart of a magnetic levitation planar motor provided in an embodiment of this application.

[0029] Figure label: 1-Motor array frame, 2-Two-dimensional Heilbeck permanent magnet array, 3-Pressure plate, 4-Printed circuit board coil unit, 5-Hall sensor array, 6-Base, 7-Non-magnetic screw, 8-Through hole, 9-Coil. Detailed Implementation

[0030] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0031] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, the application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] Related solutions using flexible printed circuit boards (FPCs) or traditional rigid circuit boards are limited by interlayer connection processes (such as reliance on external flying wires, complex interlayer connection boards, or thermoforming processes), making it difficult to achieve safe and reliable multi-layer series connection under high current, thus limiting the effective number of coil turns. To achieve the required driving thrust, extremely high currents are often forced in, which not only increases the burden on the drive power supply but also drastically exacerbates the stator's heating problem. Furthermore, in electromagnetic topology design, related technologies often employ three-phase windings or helical winding structures, which inherently possess nonlinear residuals during multi-degree-of-freedom motion decoupling, easily generating excessive parasitic torque and reactive power losses. This reactive power loss not only reduces positioning accuracy but also further converts into heat, intensifying the stator's thermal load. In addition, most current magnetic levitation planar motors heavily rely on external sensors (such as laser interferometers) for attitude monitoring, resulting in large system size, high cost, and optical path obstruction issues, making it difficult to meet the expansion requirements of multiple movers operating independently on the same platform.

[0033] Furthermore, in terms of control, this motor is a strongly nonlinear multi-input multi-output coupled system. The distortion of the air gap magnetic field and the motion coupling effect increase the difficulty of modeling and decoupling. Traditional linear control methods struggle to balance dynamic response and steady-state accuracy. Traditional model predictive control (MPC) is limited in accuracy due to its linearized model, while nonlinear model predictive control (NMPC) faces challenges in engineering implementation. Moreover, there are still shortcomings in key industry components, resulting in high product costs, insufficient compatibility, and difficulty in meeting the needs of large-scale applications.

[0034] Therefore, how to achieve high-density, multi-layer, seamless series connection of high-current coils within a limited volume through innovative rigid circuit board structure design and interlayer wiring technology to solve the problems of messy end wiring and low integration; how to eliminate parasitic thrust pulsation and improve current utilization by optimizing the number of motor phases and coil spatial arrangement to effectively reduce stator heating; and how to get rid of the constraints of external sensors and achieve high-precision, low-interference built-in closed-loop feedback have become the technical bottlenecks that magnetic levitation planar motors urgently need to overcome to move towards high precision, high reliability and large-scale application.

[0035] This application achieves high-precision six-degree-of-freedom spatial motion through innovation and optimization of coil arrangement, Hall sensor array distribution, and device structure.

[0036] like Figure 1 As shown, a magnetic levitation planar motor is provided, including: a stator and a mover.

[0037] The stator includes a base 6, a Hall sensor array 5, a printed circuit board coil unit 4, and a pressure plate 3 connected sequentially from bottom to top; the printed circuit board coil unit 4 is composed of multiple layers of printed circuit boards stacked vertically, each layer of printed circuit board includes multiple sets of coils 9 and vias 8, and the coils 9 on each layer of printed circuit board are connected in series through the vias 8; the mover is located above the stator, and the mover includes a two-dimensional Heilbeck permanent magnet array 2.

[0038] The stator of this application includes, from bottom to top, a base 6, a Hall sensor array 5, a printed circuit board coil unit 4, and a pressure plate 3. The mover is located above the stator. The printed circuit board coil unit 4 is composed of multiple layers of printed circuit boards stacked perpendicularly to each other. Through the stacking structure, the symmetry of the coil layout and the magnetic field coupling efficiency are significantly improved, and edge effects and stray force interference are further suppressed. Each layer of printed circuit board includes multiple sets of coils 9 and vias 8. The coils 9 on each layer of printed circuit board are connected in series through the vias 8. By etching multiple sets of coils 9 on the circuit board, a higher current density is achieved, thereby obtaining a greater output force. Under the same current, the force output is greater and the heat generation is lower. The coils 9 on each layer of printed circuit board are connected in series through the vias 8, realizing high-density multi-layer seamless series connection of high-current coils, which can solve the problems of messy wiring and low integration.

[0039] like Figure 1As shown, the magnetic levitation planar motor includes a stator and a mover. The stator consists of two parts: a printed circuit board (PCB) coil unit 4 and a Hall sensor array 5 (or linear Hall sensor array). The Hall sensor array 5 is located at the bottom of the stator, and the PCB coil unit 4 is located above the Hall sensor array 5. A pressure plate 3 is mounted above the PCB coil unit 4. The Hall sensor array 5 (or linear Hall sensor array) is located above the base 6. For the stator, the pressure plate 3, the PCB coil unit 4, the non-magnetic screw 7, and the Hall sensor array 5 (or linear Hall sensor array) are sequentially fixed to the base 6. The two-dimensional Heilbeck permanent magnet array 2 (i.e., the main structure of the mover) is located above the PCB coil unit 4.

[0040] When current is applied to the printed circuit board coil unit 4, according to the Lorentz force law, the current in the printed circuit board coil unit 4 interacts with the two-dimensional Heilbeck permanent magnet array 2 to generate thrust and levitation force. By distributing and controlling the force, the six-degree-of-freedom non-contact high-precision motion of the magnetic levitation planar motor is realized.

[0041] In another exemplary embodiment of this application, each group of coils on the printed circuit board includes four forward conductors and four reverse conductors, and the forward and reverse conductors are paired in pairs to form a four-phase coil. The width of each group of coils is equal to the electromagnetic period of the permanent magnet, and the spatial distance between the forward and reverse conductors of the same phase is... One permanent magnet electromagnetic cycle.

[0042] The printed circuit board coil unit 4 (or rigid printed circuit board coil unit) is composed of N layers of printed circuit boards (or rigid printed circuit boards) stacked perpendicularly to each other, where N≥1. Each layer of printed circuit board (or rigid printed circuit board) contains multiple sets of coils 9 and vias 8. The end of each set of coils 9 passes through the via 8, and the coils 9 of different layers of printed circuit boards (or rigid printed circuit boards) are connected in series through the vias 8. The printed circuit boards (or rigid printed circuit boards) are arranged orthogonally to each other, and the coil period is divided according to the electromagnetic period λ of the permanent magnet. The width of each set of coils is equal to λ. The coil is divided into eight parts according to a width of λ / 8, namely A+, B+, C+, D+, A-, B-, C-, and D-. On a single circuit board, A+, B+, C+, D+, A-, B-, C-, and D- are connected in series to form a winding. That is, a winding requires eight wires from the first layer (A+, B+, C+, D+, A-, B-, C-, and D-). The coils 9 in the same position and direction on the same layer are connected in series using vias 8 to form a four-phase coil. Each group of coils 9 consists of M turns of wire, where M>1, forming a multi-turn coil 9 in the plane.

[0043] The circuit connection between the upper and lower layers of the coil 9 on the printed circuit board is achieved by designing vias 8 on the printed circuit board (or PCB) for electrical connection.

[0044] In another exemplary embodiment of this application, the coils 9 between each layer of printed circuit boards adopt a three-dimensional series architecture that combines in-plane end folding and interlayer vertical descent. Specifically, the three-dimensional series architecture is described in terms of wire connection within one pole pitch: one pole pitch is divided into 8 wires, in the order of A+, B+, C+, D+, A-, B-, C-, D-. Taking the first group of the first layer in the X direction as an example, the wire is added from the beginning of A+, the end of A+ is connected to the end of A- through a jumper, and then the top of A- is connected to the beginning of A+ in the third layer through a via, and so on to the bottom X direction layer. Other phases are connected in the same way.

[0045] In another exemplary embodiment of this application, the printed circuit board coil unit 4 adopts a method in which the windings in the X direction and Y direction are arranged alternately and orthogonally layer by layer.

[0046] In another exemplary embodiment of this application, the mover further includes a mover array frame 1, in which a groove is provided, and the two-dimensional Hellbeck permanent magnet array 2 is installed in the groove. The two-dimensional Hellbeck permanent magnet array 2 is adhered to the groove using polyurethane methacrylate adhesive. The two-dimensional Hellbeck permanent magnet block of this application can be firmly adhered to the groove of the mover array frame 1 according to the design scheme using polyurethane methacrylate adhesive.

[0047] In another exemplary embodiment of this application, the base 6, Hall sensor array 5, printed circuit board coil unit 4, and pressure plate 3 are fixed by non-magnetic screws 7. The non-magnetic screws 7 are disposed on the edges of the Hall sensor array 5 (or linear Hall sensor array) and the printed circuit board coil unit 4 for fixing purposes.

[0048] In another exemplary embodiment of this application, the two-dimensional Heilbeck permanent magnet array 2 includes a plurality of Heilbeck permanent magnet blocks.

[0049] In another exemplary embodiment of this application, the via 8 is a rounded rectangular slot.

[0050] The magnetic levitation planar motor of this application achieves higher current density and thus greater output force by etching multiple sets of coils 9 on a printed circuit board. Under the same current, the force output is greater and the heat generation is lower. The permanent magnet block (or two-dimensional Hellbeck permanent magnet array 2) used as the stator has an inherent period, and the period of each set of coils 9 in the coil unit is equal to that of the permanent magnet block (or two-dimensional Hellbeck permanent magnet array 2). The four-phase coil current is driven and controlled by an orthogonal layered stacking connection method, simplifying the decoupling and calculation process. Due to the use of multi-layer rigid printed circuit boards, the processing precision is extremely high, greatly reducing errors and improving the structure. Extremely thin, small in size, and lightweight; the rigid printed circuit board process combined with the multi-layer circuit board stacking structure significantly improves the symmetry of the coil layout and the magnetic field coupling efficiency, further suppressing edge effects and stray force interference; the printed circuit board coil unit 4 (or rigid printed circuit board coil unit) and the Hall sensor array 5 are fixed with non-magnetic screws 7, which has the advantage of easy disassembly in terms of structure. When local hardware (such as a coil overload burnout or a single sensor failure) malfunctions, only the non-magnetic screws 7 need to be removed to achieve non-destructive separation and independent replacement of the module, avoiding the high scrap cost of traditional integrated stators.

[0051] This application also provides a control method for a magnetically levitated planar motor, including: Based on the Lorentz force principle, an electromagnetic analytical model is established to describe the mapping relationship between coil current and electromagnetic force or torque.

[0052] Construct the force-current Jacobian transformation matrix for the real-time pose of the six-DOF mover.

[0053] Based on the outer-loop nonlinear model predictive controller, the globally optimal six-degree-of-freedom force or torque command is calculated according to the deviation between the input reference trajectory and the real-time pose feedback from the Hall sensor array 5, while satisfying the physical constraints of the motor.

[0054] The inner loop responds to the globally optimal six-degree-of-freedom force or torque command. Using the Jacobian transformation matrix updated in real time with the pose, the six-degree-of-freedom force or torque command issued by the outer loop is decoupled into independent current commands for each phase coil 9 through matrix inverse operation.

[0055] Based on the independent current commands of each phase coil 9, dynamic commutation and current distribution are performed through the current driver, so that the mover can obtain precise electromagnetic force or torque, and realize the control of the mover's six degrees of freedom motion.

[0056] Specifically, the control method of this magnetic levitation planar motor includes: establishing an electromagnetic analytical model based on the Lorentz force principle to accurately describe the mapping relationship between coil current and electromagnetic force / torque. Specifically, the electromagnetic analytical model establishes an analytical expression for the spatial magnetic flux density distribution vector B of the two-dimensional Heilbeck permanent magnet array 2 through Fourier series expansion; by cross-multiplying the current density vector J in the coil unit 4 of the printed circuit board with the magnetic flux density vector B, and performing a volume integral within the effective volume V of the energized coil, the three-dimensional electromagnetic force acting on the mover is calculated. By combining the lever arm vector r from the center of mass of the mover to the point of force application of the infinitesimal element, the three-dimensional electromagnetic torque is calculated. Based on this, a pose-dependent force-current Jacobian transformation matrix is ​​constructed. Where η is the real-time six-degree-of-freedom pose of the mover, and the elements in this matrix represent the generalized force vector of the six-degree-of-freedom pose of the mover under a specific pose, with respect to the unit current of each phase coil. The contribution weights (including three force and three torque components) satisfy a linear mapping relationship. ,in This represents the input current vector of each phase coil. In the motion control stage, the outer-loop NMPC (Nonlinear Model Predictive Control) controller is used as the core. A target cost function is constructed based on the input reference trajectory and the real-time pose deviation fed back by the Hall sensor array. Under the conditions of satisfying the maximum motor current, voltage, and dynamic physical constraints, an optimization problem that minimizes position tracking error and control energy consumption is solved online in a rolling manner, thereby calculating the globally optimal six-degree-of-freedom force / torque command. The inner loop responds quickly to this command, utilizing the Jacobian transformation matrix updated in real-time pose. Through matrix pseudo-inverse operation (i.e. The optimal force / torque command issued by the outer ring will be used. Precise decoupling allows for the calculation of the independent optimal current command for each phase coil. Subsequently, dynamic commutation and current distribution are performed through a current driver, enabling the two-dimensional Heilbeck permanent magnet array 2 of the mover to obtain precise driving force / torque, ultimately eliminating coupling interference between multiple degrees of freedom and realizing precise closed-loop control of six-degree-of-freedom motion.

[0057] The magnetic levitation planar motor of this application will be described in detail below.

[0058] This application provides a six-degree-of-freedom moving magnet type magnetic levitation planar motor, such as Figure 1As shown, its stator is composed of a base 6, a Hall sensor array 5 (or a linear Hall sensor array), a non-magnetic screw 7, a printed circuit board coil unit 4 (or a rigid printed circuit board coil unit), and a pressure plate 3 stacked together. The mover consists of a two-dimensional Hellbeck permanent magnet array 2 and a mover array frame 1. After applying current to the printed circuit board coil unit 4 (or the rigid printed circuit board coil unit) below the two-dimensional Hellbeck permanent magnet array 2, according to the Lorentz force law, the printed circuit board coil unit 4 (or the rigid printed circuit board coil unit) interacts with the two-dimensional Hellbeck permanent magnet array 2 to generate thrust and levitation force. By distributing and controlling the force, the six degrees of freedom (forward and backward, up and down, left and right, rotation, pitch, and yaw) non-contact high-precision motion of the magnetic levitation planar motor is realized.

[0059] The printed circuit board coil unit 4 (or rigid printed circuit board coil unit) is composed of N layers of printed circuit boards (or rigid printed circuit boards) stacked perpendicularly to each other, where N is an integer greater than 1. For example... Figures 2-4 As shown, where, Figure 2 The "X" in the diagram represents a package designation. Figure 2 This indicates that the direction of coil 9 on the first layer of the printed circuit board is the X direction. Figure 3 The direction of coil 9 on the last printed circuit board is defined as the Y direction. Taking the X-direction coil as an example, based on the electromagnetic cycle λ of the permanent magnet, eight straight wires are arranged in parallel and closely within each permanent magnet electromagnetic cycle λ, defined sequentially as A+, B+, C+, D+, A-, B-, C-, and D-. A strict insulating safety distance is maintained between adjacent wires. Specifically, the positive-direction wires (such as A+) and the negative-direction wires (such as A-) with the same phase are physically separated by half a permanent magnet electromagnetic cycle (i.e., one pole pitch τ) to perfectly match the phase reversal characteristics of the magnetic fields of adjacent N and S poles of the mover Hellbeck array. In a complete series circuit of a single-phase winding, this application abandons the traditional planar spiral winding or external jumper process and adopts a three-dimensional series mechanism that combines "in-plane end folding back and interlayer vertical diving": In the first layer of the circuit board, the driving current flows into the head of A+ from the input terminal and generates a positive thrust by passing through the effective working area in a straight line; when the current reaches the non-working area at the edge of the board, it is folded back laterally through the in-plane U-shaped copper trace to the tail of the A- conductor, which is half a cycle away; then, the current flows back in the opposite direction in the A- conductor. Since the polarity of the mover magnetic field directly above it is also reversed at this time (from the N pole to the S pole), according to the Lorentz force vector cross product principle (F=I×B), the reverse current and the reverse magnetic field generate an effective electromagnetic thrust that is completely in the same direction as the A+ conductor, which completely avoids the phenomenon of parasitic torque and thrust cancellation. Furthermore, when the current flows back along the A- conductor to the non-working area at the starting end, it no longer coils in the plane, but instead passes through a high-current via located in the edge region, vertically descending through the insulating dielectric layer and directly connecting to the head of the conductor at the same position in the next co-directional coil layer.

[0060] This three-dimensional series architecture based on the edge non-working area ensures that there are only absolutely straight and parallel conductors in the effective working area of ​​the stator, eliminating electromagnetic coupling distortion and local overheating hotspots caused by the crossing of the end windings at the physical level. On the other hand, it realizes seamless series connection of multi-layer thick copper inside the PCB through a high-density via matrix, reconstructing the originally low-impedance single-layer conductors into high-ampere-turn multi-turn composite coils, which greatly reduces the amplitude requirement of the required drive current and lays a decisive hardware foundation for the miniaturization and high thrust density of the system.

[0061] First, the assembly of the magnetic levitation planar motor will be explained. For example... Figure 1 As shown, the six-degree-of-freedom moving-magnet magnetic levitation planar motor of this application achieves efficient operation through a series of precise assembly steps. First, the mover consists of a two-dimensional Hellbeck permanent magnet array 2 and a mover array frame 1. The mover array frame 1 has specific grooves, and the two-dimensional Hellbeck permanent magnet array 2 is arranged as follows... Figures 5-6 The arrangement is as shown. Figure 5 This is a top view of a Heilbeck permanent magnet array provided in an embodiment of this application. Regions Y1 and Y3 represent magnetization directions along the vertical Y-axis, and regions X2 and X4 represent magnetization directions along the horizontal X-axis. Figure 6This is a side view of a Hellbeck permanent magnet array provided in an embodiment of this application. 2λ represents the electromagnetic cycle of the permanent magnets within the same region (e.g., Y1, X2, Y3, or X4), and the arrows indicate the arrangement direction of the permanent magnets in the Hellbeck permanent magnet array. These two-dimensional Hellbeck permanent magnet arrays 2 are bonded to the grooves of the mover array frame 1 according to the design using polyurethane methacrylate adhesive, forming a robust and integrated motion unit. The stator consists of a base 6, a Hall sensor array 5 (or a linear Hall sensor array), non-magnetic screws 7, a printed circuit board coil unit 4 (or a rigid printed circuit board coil unit), and a pressure plate 3. The base 6 has four precise positioning threaded holes to ensure accurate alignment of other components. The remaining Hall sensor array 5 (or linear Hall sensor array), printed circuit board coil unit 4 (or rigid printed circuit board coil unit), and pressure plate 3 are all equipped with corresponding four positioning holes and are precisely installed using non-magnetic screws 7. Further, the manufacturing process and interlayer electrical connection structure of the printed circuit board coil unit 4 (or rigid printed circuit board coil unit) are described. Each layer of printed circuit board (or rigid printed circuit board) is laminated with multiple layers of high-resin prepreg, which are then bonded to the top of the next layer. When dealing with thick copper foil traces, this process utilizes the resin's excellent fluidity under high temperature and pressure to perfectly fill the deep trenches between thick copper conductors, ensuring absolutely full filling without voids or delamination, thus forming a multi-layered structure with extremely high three-dimensional mechanical rigidity. The printed circuit board coil unit 4 (or rigid printed circuit board coil unit) uses an alternating orthogonal arrangement of X-direction and Y-direction windings. This highly symmetrical physical topology in the Z-axis direction ensures that the equivalent center plane of the electromagnetic thrust in the X and Y directions perfectly coincides with the stator neutral plane, eliminating the torque caused by asymmetrical wiring at its source. In high-current interlayer series structures, compared to the commonly used flexible printed circuit board (FPC) and flexible interlayer connector board for thermoforming, this method is prone to solder joint electromigration fatigue and mechanical tearing under long-term high-current heating and high-frequency Lorentz force vibration. Therefore, this application proposes a highly reliable bridging mechanism. All in-phase coils 9 penetrate to the PCB surface through elongated slot-shaped vias (i.e., rounded rectangular slots) with rounded corners in their non-working areas. The rounded corner design of the vias 8 effectively suppresses the current congestion effect and local overheating that are easily caused by right-angled edges under high-current conditions. Based on this, this application abandons the fragile thin-film connectors and uses customized U-shaped large-diameter copper jumpers directly inserted into the slot-shaped vias, and completes the series electrical connection of each layer of coils 9 through a high-power wave soldering process.This connection structure not only enhances the interlayer series current-carrying capacity to the peak limit of the system design, but also, with its indestructible mechanical shear resistance, completely solves the technical pain point of easy fatigue fracture at the end connection point of the magnetic levitation planar motor under extremely high acceleration and deceleration impact, ensuring the ultimate reliability of the entire rigid stator base 6 under the strong coupling environment of multiple physical fields of heat, magnetism, and force. The printed circuit board coil unit 4 (or rigid printed circuit board coil unit) and the Hall sensor array 5 (or linear Hall sensor array) are fixed by positioning holes and non-magnetic screws 7 for real-time monitoring of the six degrees of freedom motion of the stator. Compared with traditional welding, this design has the convenience of disassembly. A certain gap is left between the two to promote air flow and prevent the two boards from overheating during operation and interfering with the normal operation of the system. Below the Hall sensor array 5 (or linear Hall sensor array) is the base 6, which is mounted on an optical vibration isolation platform to reduce the impact of external vibration on the system and ensure that the system can perform high-precision motion and monitoring as planned.

[0062] Secondly, the overall hardware architecture of the six-degree-of-freedom moving-magnet magnetic levitation planar motor designed in this application is described. For example... Figure 7 The overall hardware block diagram required for this magnetic levitation planar motor is presented. The hardware system of this application achieves efficient operation through the collaborative work of a series of digital, modular precision components. At the sensing end, a high-density Hall array on the sensor board located at the bottom of the stator senses the magnetic field changes of the mover permanent magnet array in real time and converts them into analog voltage signals. To optimize hardware resources and improve anti-interference capability, the signal is switched and reduced in dimension by an onboard analog multiplexer, and then sent to the data acquisition microcontroller to complete high-speed analog-to-digital conversion. The microcontroller packages the digital magnetic field data of the entire array and transmits it to the control center at high speed and without loss via Ethernet. The dSPACE real-time simulation computer serves as the control center, and Simulink Realtime is used for programming and debugging. Based on the received magnetic field data, it calculates the six-degree-of-freedom pose of the mover and calculates the required three-dimensional electromagnetic force through the control algorithm, and then distributes the excitation current commands decoupled into each coil. Subsequently, dSPACE sends the digital current commands to the distributed four-phase current driver via the CAN industrial bus. At the execution end, after receiving the command, the current driver uses its internal H-bridge power amplifier circuit to convert the DC voltage of the bus into a precise drive current, which is then injected into the multi-layer thick copper coils of the stator power board. When the coils are energized, the mover permanent magnet array undergoes six-degree-of-freedom spatial displacement under the action of the Lorentz force. The magnetic field changes caused by the displacement are again captured in real time by the bottom Hall sensor array 5, thus forming a high-frequency, anti-interference, and highly integrated hardware digital closed-loop system, ensuring the high precision and high stability of the magnetic levitation motor operation.

[0063] Next, the control system of the six-degree-of-freedom moving magnet magnetic levitation planar motor designed in this application will be described. Figure 8 A control block diagram of a magnetic levitation planar motor is presented. The control system of this magnetic levitation planar motor first receives six-degree-of-freedom target trajectory data (including three-axis translation and three-axis rotation attitude) from a host computer and calculates the spatial deviation between the target pose and the current actual pose in real time. Based on this error vector, the system uses a kinematic controller (such as PID or model predictive control) combined with the six-degree-of-freedom rigid body dynamics model of the mover to calculate the required three-dimensional electromagnetic force and three-dimensional electromagnetic torque of the mover in the global coordinate system. To achieve precise multi-dimensional control, the system first decouples the global force and torque requirements and distributes them to four independent Halbach permanent magnet arrays at the bottom of the mover through a force distribution matrix. For a single permanent magnet array, the system further utilizes dq transformation technology based on spatial position to deeply decouple the vertical levitation force from the horizontal thrust, thereby independently calculating the expected electromagnetic force values ​​in each direction. Subsequently, based on the decoupled single-array electromagnetic force requirements, the system accurately calculates the four-phase excitation current command for the corresponding area of ​​the stator PCB, ensuring that each phase coil can accurately generate the expected driving magnetic field. Driven directly by electromagnetic force, the mover will generate precise six-degree-of-freedom spatial displacement. Meanwhile, compared with black-box fitting algorithms (such as neural networks) that rely on massive analog cable connections and high computational power consumption in related technologies, this application proposes a high-frequency, low-latency pose reconstruction architecture based on hardware dimensionality reduction reuse and spatial orthogonal analysis.

[0064] Specifically, the system utilizes a high-density Hall sensor array 5 arranged at the bottom layer of the stator, and aggregates signals through an innovatively designed chip select grouping and channel parallel multiplexing acquisition circuit. This circuit divides the globally large sensor array into several independently enabled sub-arrays. Within the same control cycle, multiple multiplexers are synchronously driven through a shared underlying address bus, thereby reducing and converging dozens or even hundreds of weak analog magnetic field signals at the physical layer into a very small number of parallel output buses. This not only significantly reduces the interface resources and hardware costs of the analog-to-digital converter (ADC), but also fundamentally eliminates electromagnetic crosstalk caused by dense, long-distance analog cables under strong current drive. After acquiring clean array magnetic field data, the system reconstructs the six-degree-of-freedom absolute pose of the mover in real time using a unique pose calculation algorithm (cleverly utilizing the specific spatial fractional-order periodic relationship between the physical spacing of the Hall sensors and the pole distance of the mover's permanent magnet). Subsequently, abandoning iterative optimization or time-consuming fitting calculations, the system directly uses pure algebraic analytical models such as the arctangent function and exponential decay inverse operation to accurately calculate the six-degree-of-freedom pose of the mover with extremely low latency. This real-time feedback mechanism, combining "lower-level hardware isolation and dimensionality reduction with upper-level spatial orthogonal analysis," ensures the system's steady-state resolution and the real-time nature of the closed-loop data flow. This allows the difference between the actual position and the target position to be continuously and smoothly eliminated by advanced controllers such as high-speed NMPC. This high-speed closed-loop feedback mechanism enables the deviation between the actual pose of the mover and the target trajectory to continuously converge until the system's preset high-precision six-degree-of-freedom suspension and positioning requirements are fully met.

[0065] This application provides a six-degree-of-freedom moving-magnet magnetic levitation planar motor manufactured using multilayer printed circuit board technology. By etching multiple sets of coils 9 on the circuit board, a higher current density is achieved, resulting in greater output force. Under the same current application, the force output is greater and the heat generation is lower. The permanent magnet block used as the stator has an inherent period. The period of each set of coils 9 in the coil unit is equal to that of the permanent magnet block. The four-phase coil current is driven and controlled by an orthogonal layered stacking method, simplifying the decoupling and calculation process. Due to the use of multilayer rigid circuit boards, the processing precision is extremely high, greatly reducing errors. The structure is extremely thin, small in size, and lightweight. Lightweight; the rigid circuit board process combined with the multi-layer circuit board stacking structure significantly improves the symmetry of the coil layout and the magnetic field coupling efficiency, further suppressing edge effects and stray force interference; the printed circuit board coil unit (or rigid printed circuit board coil unit) and the Hall sensor array 5 are fixed with non-magnetic screws 7. Compared with the integrated or flexible stacked structure that is often used in related technologies to tightly bond the coil and the sensor through potting, gluing or hot pressing welding, it has the following advantages: (1) The coil board under high current drive is the main heat source of the system. The studs are used to support the two boards at equal intervals to form a natural convection air isolation layer. This design cuts off the direct conduction path of coil heat to the bottom sensor, fundamentally eliminating the problem of severe zero-point temperature drift of Hall sensor caused by thermal coupling in the tightly fitted structure, ensuring extremely high precision magnetic field signal acquisition; (2) The use of completely non-magnetic structural components (nylon or special non-magnetic alloy) for positioning support avoids the generation of eddy current loss or magnetic field distortion in conventional metal structural components under high frequency drive and strong motor magnetic field alternation environment, thereby ensuring the purity of the magnetic field in the space where the Hall sensor is located.

[0066] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0067] This document uses specific examples to illustrate the principles and implementation methods of this application. The descriptions of the above embodiments are only for the purpose of helping to understand the methods and core ideas of this application. Furthermore, those skilled in the art will recognize that, based on the ideas of this application, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of this application.

Claims

1. A magnetically levitated planar motor, characterized in that, include: The stator includes, from bottom to top, a base, a Hall sensor array, a printed circuit board coil unit, and a pressure plate; The printed circuit board coil unit is composed of multiple printed circuit boards stacked vertically on each other. Each printed circuit board includes multiple sets of coils and vias. The coils on each printed circuit board are connected in series through the vias. The mover is located above the stator and comprises a two-dimensional Heilbeck permanent magnet array.

2. The magnetic levitation planar motor according to claim 1, characterized in that, Each coil group on the printed circuit board includes four forward conductors and four reverse conductors, with each pair of forward and reverse conductors forming a four-phase coil. The width of each coil group is equal to the electromagnetic period of the permanent magnet, and the spatial distance between the forward and reverse conductors of the same phase is... One permanent magnet electromagnetic cycle.

3. The magnetic levitation planar motor according to claim 1, characterized in that, The coils between each layer of printed circuit boards adopt a three-dimensional series architecture that combines in-plane end folding and interlayer vertical diving.

4. The magnetic levitation planar motor according to claim 1, characterized in that, The printed circuit board coil unit adopts a method of alternating orthogonal arrangement of windings in the X and Y directions layer by layer.

5. The magnetic levitation planar motor according to claim 1, characterized in that, The mover also includes a mover array frame, in which a groove is provided, and the two-dimensional Heilbeck permanent magnet array is installed in the groove.

6. The magnetic levitation planar motor according to claim 5, characterized in that, The two-dimensional Heilbeck permanent magnet array is bonded to the groove using polyurethane methacrylate adhesive.

7. The magnetic levitation planar motor according to claim 1, characterized in that, The base, Hall sensor array, printed circuit board coil unit, and pressure plate are fixed by non-magnetic screws.

8. The magnetic levitation planar motor according to claim 1, characterized in that, The two-dimensional Heilbeck permanent magnet array comprises multiple Heilbeck permanent magnet blocks.

9. The magnetic levitation planar motor according to claim 1, characterized in that, The via is a rounded rectangular slot.

10. A control method for a magnetically levitated planar motor according to any one of claims 1-9, characterized in that, include: Based on the Lorentz force principle, an electromagnetic analytical model is established to describe the mapping relationship between coil current and electromagnetic force or torque. Construct the force-current Jacobian transformation matrix for the real-time pose of the six-DOF mover; Based on the outer-loop nonlinear model predictive control controller, the globally optimal six-degree-of-freedom force or torque command is calculated according to the deviation between the input reference trajectory and the real-time pose feedback from the Hall sensor array, while satisfying the physical constraints of the motor. The inner loop responds to the globally optimal six-degree-of-freedom force or torque command. Using the Jacobian transformation matrix updated in real time with pose, the six-degree-of-freedom force or torque command issued by the outer loop is decoupled into independent current commands for each phase coil through matrix inverse operation. Based on the independent current commands of each phase coil, dynamic commutation and current distribution are performed through a current driver, enabling the mover to obtain precise electromagnetic force or torque, and realizing the control of the mover's six degrees of freedom motion.

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