A kind of opposite reluctance linear actuator of attraction and repulsion synergic drive and thrust non-linear inhibition and design method thereof

Abstract

The application provides a kind of opposite reluctance linear actuator of attraction and repulsion synergistic drive and thrust nonlinear inhibition and design method thereof, belongs to electromagnetic linear actuator field, solves the technical problems that existing reluctance linear actuator cannot simultaneously realize bidirectional drive without additional reset mechanism in short stroke, structural level thrust nonlinear inhibition, output thrust changes with air gap and presents strong nonlinear and large fluctuation, high-precision control difficulty is high.The application adopts the topology of opposite double stator and central rotor reluctance actuator, through the same direction synergistic drive mode of one side attraction and one side repulsion, uses the slope compensation effect of complementary air gap, cooperates with parameter optimization design method to inhibit thrust nonlinearity.It can be bidirectional driven without additional reset mechanism, improve thrust density, reduce thrust fluctuation from structural level, reduce high-precision control difficulty, adapt to short-stroke precision driving scene.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic linear actuators, and in particular to an opposed magnetoresistive linear actuator with attraction-repulsion cooperative drive and thrust nonlinear suppression, and its design method. Background Technology

[0002] In high-precision positioning platforms, precision manufacturing equipment, and micro-displacement drive systems, short-stroke linear actuators typically require high positioning accuracy, high dynamic response, and stable output thrust within a millimeter-level stroke range. In existing technologies, voice coil motors have a large working air gap, which easily leads to high copper losses and heat generation under high-current drive conditions, increasing the system's heat dissipation pressure. Furthermore, due to limitations in magnetic circuit structure and current density, further increasing the thrust density of voice coil motors is quite difficult.

[0003] Compared to voice coil motors, reluctance linear actuators can utilize soft magnetic materials and a smaller working air gap to form a high-permeability magnetic circuit, potentially achieving higher thrust density within the same volume. A relatively close existing technical solution is the single-sided CI-type reluctance actuator, which typically consists of a C-shaped stator, an I-shaped mover, and an excitation coil wound around the stator. When energized, the mover moves towards the stator under the influence of magnetic resistance, outputting a linear driving force. However, this type of structure relies primarily on a single-sided magnetic circuit to attract the mover, making it naturally more suitable for unidirectional attraction actuation. To achieve bidirectional motion (forward and reverse), a reset mechanism, elastic elements, an external reverse drive device, or another actuator is usually required, leading to structural complexity, increased size, and reduced system integration and control consistency.

[0004] Meanwhile, the output force of the reluctance actuator is highly sensitive to the working air gap. During the movement of the mover, changes in the air gap cause changes in the magnetic circuit permeability, magnetic flux density, and local saturation state, resulting in a significant nonlinearity in the output thrust with displacement. This is especially true in the small air gap region, where sudden thrust changes and large thrust fluctuations are likely to occur. The aforementioned nonlinearity increases the difficulty of high-precision closed-loop control, making it difficult for the controller to use a uniform linear model and fixed control gain throughout the entire stroke. It often requires complex feedforward compensation, lookup table compensation, or piecewise control, and the compensation effect depends on the model accuracy and parameter stability. It is impossible to suppress the nonlinearity of force output caused by air gap changes from the actuator topology itself. Summary of the Invention

[0005] This invention provides a counter-rotating reluctance linear actuator and its design method with attraction and repulsion synergistic drive and thrust nonlinearity suppression. By adopting a reluctance actuator topology in which the first stator and the second stator are opposed along the direction of motion of the mover and the mover is centrally located, a synergistic drive mode is constructed in which one side of the magnetic circuit generates attraction and the other side generates repulsion in the same direction of motion. The slope of the attraction curve and the repulsion curve are compensated by utilizing the complementary change relationship between the working air gaps on both sides with the displacement of the mover. The output force stability is optimized by matching and compensating the reference air gap, pole area, excitation state and repulsion magnetic source parameters. This solves the technical problems of existing reluctance linear actuators that cannot simultaneously achieve bidirectional drive without additional reset mechanism and thrust nonlinearity suppression at the structural level within a short stroke, and the output thrust is highly nonlinear and fluctuates greatly with the change of air gap, making high-precision control difficult.

[0006] An opposed reluctance linear actuator with attraction-repulsion synergistic drive and thrust nonlinear suppression includes a first stator, a second stator, a mover, a first stator excitation coil, and a second stator excitation coil. The first stator and the second stator are arranged opposite each other along the direction of motion of the mover. The mover is located between the first stator and the second stator and makes a short-stroke linear motion along the line connecting the first stator and the second stator. A first working air gap is formed between the mover and the first stator, and a second working air gap is formed between the mover and the second stator. The first stator excitation coil and the second stator excitation coil are wound on the first stator and the second stator, respectively. When energized, in the same direction of motion, the magnetic circuit between the stator and the mover on one side generates an attractive force pointing in the direction of motion, while the magnetic circuit between the stator and the mover on the other side generates a repulsive force in the same direction. The attractive force and the repulsive force together constitute the effective output force of the mover.

[0007] Furthermore, the mover is a permanent magnet source mover assembly or a dual-winding excitation coil mover assembly, wherein, When the mover is a permanent magnet source mover assembly, the source is a permanent magnet structure, and the permanent magnet is located at the center point of the assembly; When the mover is a dual-winding excitation coil mover assembly, the dual-winding excitation coil mover assembly consists of a polarity-configured winding structure composed of two independent excitation coils on the left and right sides.

[0008] Furthermore, let the direction of motion of the mover be the x-axis, and x=0 when the mover is in the intermediate reference position, and the reference air gap be the compensation reference air gap. The first working air gap is The second working air gap is When the mover is displaced by x, the air gaps on both sides satisfy:

[0009]

[0010] When the mover moves, the air gap on one side increases and the air gap on the other side decreases. The two air gaps change in a complementary manner. To avoid contact between the mover and the stator, the air gaps on both sides must satisfy the following:

[0011] In the formula, Indicates the minimum permissible working air gap. Indicates the maximum permissible working air gap.

[0012] Furthermore, when the mover moves in the forward direction, the stator on the forward side is the attraction side and the stator on the reverse side is the repulsion side. The attraction and repulsion forces are superimposed in the same direction, driving the mover to move in the forward direction. When the mover moves in the opposite direction, the attraction / repulsion states of the stators on both sides are reversed, and the attraction and repulsion forces are superimposed in the same direction, driving the mover to move in the opposite direction.

[0013] Furthermore, taking the target motion direction as the positive direction, the effective output force of the actuator is the superposition value of the attraction and repulsion forces in the same direction. Unlike the opposed magnetoresistive actuator with differential output from both sides, the effective output force is not the difference between the attraction forces on both sides.

[0014] A thrust nonlinearity suppression design method for an opposed reluctance linear actuator, based on the aforementioned attraction-repulsion cooperative drive and thrust nonlinearity suppression, includes the following steps: S1. Construct the basic structure of the opposing magnetic reluctance linear actuator with attraction-repulsion cooperative drive, set up a first stator and a second stator opposite to each other along the motion direction of the mover, and place the mover between the two stators so that the mover forms a first working air gap with the first stator and a second working air gap with the second stator. S2. Establish an attraction-repulsion coordinated output force model. When the mover moves in one direction, one side of the magnetic circuit generates an attractive force pointing in the direction of motion, and the other side of the magnetic circuit generates a repulsive force in the same direction. The superposition value of the attractive force and the repulsive force is used as the effective output force of the actuator. S3. Based on the complementary relationship between the working air gaps on both sides and the displacement of the mover, the parameters of the compensation reference air gap, pole area, excitation state and repulsion magnetic source are adjusted to reduce the gradient of the output force as the displacement changes, so that the output force curve tends to be flat and the nonlinearity of thrust is suppressed.

[0015] Furthermore, in S2, the output force on the attraction side... and repulsive side output force They are represented as follows:

[0016]

[0017] In the formula, , These represent the number of turns of the coil on the attraction side and the repulsion side, respectively. , These represent the magnetizing currents on the attraction and repulsion sides, respectively. , These represent the effective polar areas on both sides; BH Indicates the magnetization curve of a soft magnetic material; Indicates the magnetic source parameters that generate the repulsive effect; , These represent the electromagnetic force functions on the attracting and repulsive sides, respectively.

[0018] Furthermore, in S2, taking the target motion direction as the positive direction, the effective output force of the actuator satisfies:

[0019] In the formula, The effective output force of the mover along the target direction, and the output force of a typical double-sided attracting differential output opposed reluctance actuator, satisfy the following:

[0020] In the formula, , These represent the attraction forces on the left and right sides, respectively, and represent the differential output of the attraction forces on the left and right sides.

[0021] Furthermore, in S3, the gradient of the output force as a function of displacement satisfies:

[0022] In the formula, This represents the gradient of the output force as a function of displacement. This represents the partial derivative of the attractive force with respect to the working air gap on the attraction side; This represents the partial derivative of the repulsive force with respect to the working air gap on the repulsive side.

[0023] Furthermore, in S3, thrust differential is used. and thrust volatility As an evaluation index for the stability of output force, both satisfy the following:

[0024]

[0025] In the formula, , , These represent the maximum, minimum, and average output force within the target stroke, respectively. or The smaller the value, the smoother the output force changes with displacement.

[0026] Compared with existing technologies, the present invention achieves significant beneficial effects through the above-mentioned technical solution: The present invention employs a dual stator arranged opposite each other along the direction of motion of the mover and a centrally located mover, combined with an excitation coil wound on the stator to construct an opposed magnetic reluctance linear actuator topology. This eliminates the need for additional reset mechanisms, elastic elements, or additional reverse drive devices to achieve bidirectional linear drive, effectively simplifying the overall structure, reducing device size, and improving system integration and control consistency. Simultaneously, the present invention adopts a cooperative drive mode where the magnetic circuit between one stator and the mover in the same direction of motion generates an attractive force pointing in the direction of motion, while the magnetic circuit between the other stator and the mover generates a repulsive force in the same direction. The combined value of the attractive and repulsive forces in the same direction serves as the effective output force. This differs from the traditional dual-sided attraction differential output method, achieving a higher effective output thrust under the same excitation conditions, effectively increasing thrust density, while avoiding excitation losses caused by the mutual cancellation of magnetic fields in differential output, reducing coil operating heat and energy consumption. Furthermore, this invention relies on the complementary change relationship of the working air gap between the mover and the two stators with displacement to make the attraction curve and the repulsion curve form slope compensation. It suppresses the nonlinearity of force output caused by air gap change from the actuator topology level, reduces thrust fluctuation throughout the entire stroke, and improves the stability of output force without the need for complex feedforward compensation, lookup table compensation or segmented control, effectively reducing the difficulty of high-precision closed-loop control. In addition, the mover can be implemented in two forms: a permanent magnet magnetic source mover assembly or a dual-winding excitation coil mover assembly. This can adapt to different application conditions and control requirements, improving the overall engineering applicability and configuration flexibility of the solution. The supporting thrust nonlinearity suppression design method establishes a quantitative attraction-opposition repulsion cooperative output force model, clarifies the gradient calculation relationship of output force with displacement, and uses thrust difference and thrust fluctuation rate as quantitative evaluation indicators of output force stability. This provides a clear theoretical and calculation basis for the matching optimization of compensation reference air gap, pole area, excitation state and repulsion magnetic source parameters, making it easier to achieve a reasonable trade-off between output thrust level and thrust fluctuation suppression, and ensuring that the final designed actuator can have stable and consistent output characteristics within a short stroke. Attached Figure Description

[0027] Figure 1 A schematic diagram of the structure of an opposed reluctance linear actuator of the present invention, which features attraction-repulsion cooperative driving and thrust nonlinear suppression when the mover is a permanent magnet magnetic source mover assembly; Figure 2 A schematic diagram of the structure of an opposed reluctance linear actuator of the present invention, which features attraction-repulsion cooperative driving and thrust nonlinear suppression when the mover is a dual-winding excitation coil mover assembly; Figure 3 Magnetic density cloud diagram of an opposed reluctance linear actuator; Figure 4The magnetic density cloud diagram shows the rotor being positioned 0.4 mm to the left of the center position when the rotor is subjected to a horizontal force to the right and the first stator repels and the second stator attracts it. Figure 5 The magnetic density cloud diagram shows the rotor being positioned 0.4 mm to the right of the center position when the rotor is subjected to a horizontal force to the right and the first stator repels and the second stator attracts it. Figure 6 The magnetic cloud diagram shows the magnetic field at the center position of the mover when the mover is subjected to a horizontal force to the right and the first stator repels and the second stator attracts it. Figure 7 To compensate for the reference air gap The effect on the total thrust curve is shown in the diagram. Figure 8 This is a comparison of the thrust curves of an opposing reluctance linear actuator with attraction-repulsion synergistic drive and thrust nonlinear suppression according to the present invention, and a conventional CI-type reluctance linear actuator.

[0028] Wherein, 1 is the first stator, 2 is the first stator excitation coil, 3 is the second stator, 4 is the second stator excitation coil, and 5 is the mover. Detailed Implementation

[0029] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] Reference Figures 1-8 As shown, an opposed reluctance linear actuator with attraction-repulsion cooperative drive and thrust nonlinear suppression includes a first stator 1, a second stator 3, a mover 5, a first stator excitation coil 2, and a second stator excitation coil 4. The first stator 1 and the second stator 3 are arranged opposite each other along the direction of motion of the mover 5. The mover 5 is located between the first stator 1 and the second stator 3 and makes a short-stroke linear motion along the line connecting the first stator 1 and the second stator 3. A first working air gap is formed between the mover 5 and the first stator 1, and a second working air gap is formed between the mover 5 and the second stator 3. The first stator excitation coil 2 and the second stator excitation coil 4 are respectively wound on the first stator 1 and the second stator 3. When energized, in the same direction of motion, the magnetic circuit between one stator and the mover 5 generates an attractive force pointing in the direction of motion, while the magnetic circuit between the other stator and the mover 5 generates a repulsive force in the same direction. The attractive force and the repulsive force together constitute the effective output force of the mover 5.

[0031] During the movement of the mover 5, the first working air gap and the second working air gap exhibit a complementary relationship, and the attraction curve and the repulsion curve form a slope compensation, suppressing the nonlinear change of the output thrust with displacement.

[0032] Specifically, this invention employs a first stator 1 and a second stator 3 arranged opposite each other along the motion direction of the mover 5, forming a dual-sided magnetic circuit topology with the centrally positioned mover 5. Excitation is achieved by first stator excitation coils 2 and second stator excitation coils 4 wound on the first stator 1 and second stator 3 respectively. This eliminates the need for additional reset mechanisms, elastic elements, or additional reverse drive devices, enabling bidirectional linear drive in both directions. This effectively simplifies the overall structure, reduces device size, and improves system integration and control consistency. This invention utilizes a synergistic drive mode where the magnetic circuit between one stator and mover 5 in the same motion direction generates an attractive force pointing in the direction of motion, while the magnetic circuit between the other stator and mover 5 generates a repulsive force in the same direction. This allows the attractive and repulsive forces to superimpose in the same direction, forming the effective output force of the mover 5. This differs from the traditional dual-sided attraction differential output method, which is beneficial for increasing thrust density and reducing excitation losses. Meanwhile, this invention relies on the complementary changes in the first working air gap between the mover 5 and the first stator 1, and the second working air gap between the mover 5 and the second stator 3 as the mover 5 moves, to achieve slope compensation between the attraction curve and the repulsion curve. This suppresses the nonlinearity of force output caused by air gap changes at the actuator topology level, reduces thrust fluctuations throughout the entire stroke, and improves the stability of output force without the need for complex feedforward compensation, lookup table compensation, or segmented control. This effectively reduces the difficulty of high-precision closed-loop control, improves the consistency and controllability of output force during short-stroke drive, and can better adapt to the short-stroke bidirectional drive and precision positioning control requirements in high-precision positioning platforms and precision manufacturing equipment.

[0033] Furthermore, the mover 5 is a permanent magnet source mover assembly or a dual-winding excitation coil mover assembly, wherein, When the mover 5 is a permanent magnet source mover assembly, the source is a permanent magnet structure, and the permanent magnet is located at the center point of the assembly; When the mover 5 is a dual-winding excitation coil mover assembly, the dual-winding excitation coil mover assembly consists of a polarity-configured winding structure composed of two independent excitation coils on the left and right sides.

[0034] Specifically, the mover 5 of this invention can be implemented in two forms: a permanent magnet source mover assembly or a dual-winding excitation coil mover assembly. This allows for adaptation to different application conditions and control requirements, improving the overall engineering applicability and configuration flexibility of the solution. When the mover 5 uses a permanent magnet source mover assembly, the permanent magnet is positioned at the center of the assembly. The constant magnetic field of the permanent magnet itself can form magnetic coupling with the first stator excitation coil 2 and the second stator excitation coil 4. This eliminates the need for additional power supply wiring and a sliding feed structure for the mover 5, simplifying the overall structure, reducing assembly complexity, and improving operational reliability. When the mover 5 uses a dual-winding excitation coil mover assembly, the left and right independent excitation coils form a polarity-configured winding structure. The magnetic field polarity and intensity on the mover 5 side can be flexibly adjusted by applying currents of different polarities, facilitating precise switching between the attraction and repulsion states with the stators on both sides, and adapting to more refined thrust adjustment and bidirectional drive control requirements.

[0035] Furthermore, let the direction of motion of the mover 5 be the x-axis, and x=0 when the mover 5 is in the intermediate reference position, and the reference air gap be the compensation reference air gap. The first working air gap is The second working air gap is When the mover 5 is displaced by x, the air gaps on both sides satisfy:

[0036]

[0037] When the mover 5 moves, the air gap on one side increases and the air gap on the other side decreases. The two air gaps change in a complementary manner. To prevent the mover 5 from contacting the stator, the air gaps on both sides must satisfy the following:

[0038] In the formula, Indicates the minimum permissible working air gap. Indicates the maximum permissible working air gap.

[0039] Specifically, this invention sets the direction of movement of the mover 5 as the x-axis, takes the intermediate reference position as the zero displacement point, and uses the compensation reference air gap as the reference air gap. It clarifies the complementary change relationship between the first working air gap and the second working air gap when the mover 5 is displaced, so that the air gap on one side increases and the air gap on the other side decreases during the movement of the mover 5. This provides a structural premise for the synergistic superposition of attractive and repulsive forces and the slope compensation of the force curves on both sides, ensuring that the nonlinear suppression of thrust can be stably achieved based on the air gap change law. At the same time, by limiting the minimum and maximum working air gaps, mechanical contact between the mover 5 and the first stator 1 and the second stator 3 can be avoided, ensuring the safety and reliability of the actuator operation. It also provides a clear boundary basis for the matching and optimization of structural parameters and excitation parameters.

[0040] Furthermore, when the mover 5 moves in the forward direction, the stator on the forward side is the attraction side and the stator on the reverse side is the repulsion side. The attraction and repulsion forces are superimposed in the same direction, driving the mover 5 to move in the forward direction. When the mover 5 moves in the opposite direction, the attraction / repulsion states of the stators on both sides are interchanged. The attraction and repulsion forces are superimposed in the same direction, driving the mover 5 to move in the opposite direction. This can achieve bidirectional drive without the need for an additional reset mechanism.

[0041] Specifically, this invention utilizes a working mode where the stator on the forward side acts as the attraction side and the stator on the reverse side acts as the repulsion side during the forward motion of the mover 5, and the attraction and repulsion states on both sides are interchanged during the reverse motion. This allows the mover 5 to obtain effective driving force in both forward and reverse motion directions by relying on the superposition of attraction and repulsion forces in the same direction. It achieves bidirectional linear drive without relying on a mechanical reset mechanism or additional reverse drive device, effectively simplifying the overall actuator structure and improving system integration and control consistency. Simultaneously, the cooperative drive mode of attraction on one side and repulsion on the other side in both forward and reverse motions allows the mover 5 to achieve thrust nonlinearity suppression during bidirectional motion by relying on the complementary changes in the first working air gap between the mover 5 and the first stator 1, and the second working air gap between the mover 5 and the second stator 3. The drive direction conversion can be completed simply by switching the excitation states of the first stator excitation coil 2 and the second stator excitation coil 4, ensuring good stability of the output force in both forward and reverse strokes.

[0042] Furthermore, taking the target motion direction as the positive direction, the effective output force of the actuator is the superposition value of the attraction and repulsion forces in the same direction. Unlike the opposed magnetoresistive actuator with differential output from both sides, the effective output force is not the difference between the attraction forces on both sides.

[0043] Specifically, this invention takes the target motion direction as the positive direction and sets the effective output force of the actuator to be the superposition of the attraction and repulsion forces in the same direction. This differs from the ordinary dual-sided attraction differential output opposed magnetoresistive actuator, which relies on the difference in attraction forces on both sides to obtain net output force. Under the same excitation conditions, this invention can achieve a higher effective output thrust, effectively increasing thrust density. Simultaneously, it avoids the increased excitation loss caused by the mutual cancellation of magnetic fields on both sides in the differential output method, which helps reduce the excitation energy consumption and heat generation of the first stator excitation coil 2 and the second stator excitation coil 4. This superimposed output mode in the same direction can better coordinate with the complementary changes in the first working air gap between the mover 5 and the first stator 1, and the second working air gap between the mover 5 and the second stator 3, ensuring the effective performance of the slope compensation effect of the attraction and repulsion curves. This further strengthens the effect of thrust nonlinearity suppression, improves the stability and controllability of the output thrust of the mover 5, and better adapts to the working conditions of short-stroke precision drives.

[0044] A thrust nonlinearity suppression design method for an opposed reluctance linear actuator, based on the aforementioned attraction-repulsion cooperative drive and thrust nonlinearity suppression, includes the following steps: S1. Construct the basic structure of the opposing magnetic reluctance linear actuator with attraction-repulsion coordinated drive, set the first stator 1 and the second stator 3 opposite each other along the motion direction of the mover, and place the mover 5 between the two stators so that the mover 5 forms a first working air gap with the first stator 1 and a second working air gap with the second stator 3. S2. Establish an attraction-repulsion coordinated output force model. When the mover 5 moves in one direction, one side of the magnetic circuit generates an attractive force pointing in the direction of motion, and the other side of the magnetic circuit generates a repulsive force in the same direction. The superposition value of the attractive force and the repulsive force is used as the effective output force of the actuator. S3. Based on the complementary relationship between the working air gaps on both sides and the displacement of the mover 5, the parameters of the compensation reference air gap, pole area, excitation state and repulsion magnetic source are adjusted to reduce the gradient of the output force as the displacement changes, so that the output force curve tends to be flat and the nonlinearity of thrust is suppressed.

[0045] Specifically, this invention constructs a basic structure for an opposing magnetic reluctance linear actuator with attraction-repulsion coordinated drive. It sets up a first stator 1 and a second stator 3 opposing each other along the motion direction of the mover 5, placing the mover 5 between the two stators to form a first working air gap and a second working air gap. This provides a structural foundation for the realization of the coordinated drive mode and the performance of thrust nonlinearity suppression. By establishing an attraction-repulsion coordinated output force model, the invention clarifies the force output mechanism where one side of the magnetic circuit generates an attractive force pointing in the direction of motion, while the other side generates a repulsive force in the same direction during unidirectional motion of the mover 5. The superposition value of the attractive and repulsive forces is used as the effective output force of the actuator, distinguishing it from traditional dual-drive actuators. The side-attraction differential output working mode provides an accurate theoretical basis for thrust characteristic analysis and structural parameter optimization. Based on this, relying on the complementary change relationship between the working air gaps on both sides and the displacement of the mover 5, the gradient of the output force change with displacement is reduced by adjusting the compensation reference air gap, pole area, excitation state and repulsive magnetic source parameters, so that the output force curve tends to be flat. This can achieve thrust nonlinearity suppression from the topology design level, improve the stability of the output force throughout the stroke without relying on complex control algorithm compensation, effectively reduce the difficulty of achieving high-precision closed-loop control, and provide a clear and feasible design path for opposed magnetic reluctance linear actuators with low thrust fluctuation characteristics.

[0046] Furthermore, in S2, the output force on the attraction side... and repulsive side output force They are represented as follows:

[0047]

[0048] In the formula, , These represent the number of turns in the coils on the attraction and repulsion sides, respectively. , These represent the magnetizing currents on the attraction and repulsion sides, respectively. , These represent the effective polar areas on both sides; BH Indicates the magnetization curve of a soft magnetic material; Indicates the magnetic source parameters that generate the repulsive effect; , These represent the electromagnetic force functions on the attracting and repelling sides, respectively.

[0049] Specifically, the attraction side is:

[0050]

[0051] The rejection side is:

[0052]

[0053] in, , These represent the equivalent magnetic flux densities in the working air gaps on the attraction and repulsion sides, respectively. , These represent the electromagnetic force correction coefficients on the attraction and repulsion sides, respectively. The effective polar surface area at the working air gap. Permeability in vacuum , These are the number of winding turns on the attraction and repulsion sides, respectively. , These represent the working air gap lengths on the attraction and repulsion sides, respectively. This represents the equivalent reluctance-corrected air gap determined by the magnetization curve of the soft magnetic material. This represents the equivalent air gap correction term calculated from leakage flux, edge effects, and end effects. This represents the equivalent air gap correction term obtained by converting the repulsion of the repulsive magnetic source itself.

[0054] This invention, in establishing the attraction-repulsion coordinated output force model, quantifies the output force on both the attraction and repulsion sides. It incorporates the coil turns, excitation current, effective pole area, magnetization curve of the soft magnetic material, and magnetic source parameters that generate repulsion on both sides into the output force calculation. This accurately quantifies the effect of the excitation parameters of the first stator excitation coil 2 and the second stator excitation coil 4, and the magnetic field parameters of the mover 5, on the output force of the magnetic circuits on both sides. It clearly reflects the influence mechanism of each structural and electromagnetic parameter on the output thrust, providing a clear quantitative calculation basis for the matching optimization of key parameters such as the compensation reference air gap, pole area, and excitation state. This ensures that parameter adjustments during the thrust nonlinearity suppression design process have clear theoretical guidance, improving the accuracy and feasibility of the overall design. Simultaneously, it provides a reliable model foundation for the thrust characteristic analysis of the actuator and the formulation of excitation control strategies, ensuring that the output effect and thrust stability optimization of the attraction-repulsion coordinated drive achieve the expected design goals.

[0055] Furthermore, in S2, taking the target motion direction as the positive direction, the effective output force of the actuator satisfies:

[0056] In the formula, This represents the effective output force of the mover 5 along the target direction. The output force of a typical double-sided attracting differential output opposed reluctance actuator satisfies the following:

[0057] In the formula, , These represent the attraction forces on the left and right sides, respectively, and represent the differential output of the attraction forces on the left and right sides.

[0058] Specifically, the total output force is:

[0059] This invention clarifies that the effective output force of the actuator when the target motion direction is positive is the superposition value of the attractive and repulsive forces in the same direction. It also provides a corresponding output force calculation method for a conventional dual-sided attraction differential output opposed reluctance actuator, clearly demonstrating the fundamental difference between this solution and the traditional opposed reluctance structure in terms of output mechanism. This unidirectional superposition output mode avoids the excitation loss caused by the mutual cancellation of attractive forces on both sides in the differential output method. Under the same excitation conditions of the first stator excitation coil 2 and the second stator excitation coil 4, a higher effective output thrust can be obtained, effectively improving the thrust density of the actuator and reducing coil excitation energy consumption and operating heat generation. Simultaneously, this output calculation relationship can accurately match the complementary changes in the working air gap characteristics between the mover 5 and the first stator 1 and the second stator 3, providing accurate quantitative basis for subsequent thrust slope compensation and nonlinear suppression design based on the complementary air gap relationship. This ensures the calculation accuracy and actual implementation effect of output force stability optimization, enabling the final designed actuator to possess both high output density and low thrust fluctuation characteristics in short-stroke bidirectional drive scenarios.

[0060] Furthermore, in a single-sided reluctance actuator, when the air gap decreases, the reluctance decreases and the magnetic flux density increases, causing the attractive force to change drastically within the small air gap range, resulting in force-displacement nonlinearity. This invention utilizes the complementary relationship of a decreasing air gap on the attraction side and an increasing air gap on the repulsion side to compensate for the force curves on both sides. In S3, the gradient of the output force as a function of displacement satisfies:

[0061] In the formula, This represents the gradient of the output force as a function of displacement. This represents the partial derivative of the attractive force with respect to the working air gap on the attraction side; This represents the partial derivative of the repulsive force with respect to the working air gap on the repulsive side.

[0062] Specifically, this invention clarifies the quantitative relationship between the gradient of output force change with displacement and the partial derivatives of the attraction force with respect to the attraction side working air gap and the partial derivatives of the repulsion force with respect to the repulsion side working air gap. This clearly reveals the intrinsic mechanism of slope compensation between the attraction and repulsion curves, and intuitively reflects the combined influence of the output characteristics of the magnetic circuits on the stability of the total output force when the first working air gap between the mover 5 and the first stator 1 and the second working air gap between the mover 5 and the second stator 3 exhibit complementary changes during the displacement of the mover 5. Based on this gradient calculation relationship, the smoothness of the output force curve under different structural and excitation parameters can be accurately evaluated during the design process. This provides clear quantitative guidance for adjusting the compensation reference air gap, pole area, excitation state, and repulsion magnetic source parameters, facilitating the targeted reduction of the gradient of output force change with displacement, making the output force curve smoother, ensuring the design effect of thrust nonlinear suppression at the topological level, and effectively improving the accuracy and feasibility of thrust characteristic optimization for opposed reluctance linear actuators.

[0063] Furthermore, in S3, thrust differential is used. and thrust volatility As an evaluation index for the stability of output force, both satisfy the following:

[0064]

[0065] In the formula, , These represent the maximum and minimum output forces within the target stroke, respectively. or The smaller the value, the smoother the output force changes with displacement. When the mover 5 moves in the forward direction, the forward side is the attraction side and the reverse side is the repulsion side. The two sides work together in the same direction to push the mover 5 in the forward direction. When the mover 5 moves in the reverse direction, the attraction / repulsion states on both sides are reversed, and the mover 5 moves in the reverse direction. Therefore, this invention can achieve bidirectional driving in both directions without relying on a mechanical reset mechanism or a conventional double-sided attraction and pull method.

[0066] Specifically, this invention uses thrust difference and thrust fluctuation rate as evaluation indicators for output force stability and clarifies their calculation relationship. This allows for the quantitative characterization of the fluctuation degree of the output thrust of the mover 5 within the target stroke, providing a unified and quantifiable evaluation standard for assessing the effect of thrust nonlinearity suppression. This provides a clear and comparable quantitative basis for the analysis and optimization of thrust stability. During the design process of adjusting the compensation reference air gap, pole area, excitation state, and repulsive magnetic source parameters, the output stability under different parameter combinations can be intuitively compared through thrust difference and thrust fluctuation rate. This facilitates the selection of the optimal design scheme, achieving a reasonable trade-off between output thrust level and thrust fluctuation suppression. It ensures that the final designed opposed reluctance linear actuator can achieve attraction and repulsion coordinated drive based on the opposed topology formed by the first stator 1, the second stator 3, and the mover 5, in conjunction with the excitation control of the first stator excitation coil 2 and the second stator excitation coil 4. This results in a stable and consistent output thrust throughout the entire stroke, effectively reducing the difficulty of achieving high-precision closed-loop control.

[0067] The following is a specific embodiment of the present invention: The key innovations of this invention are: first, proposing an opposed magnetoresistive drive structure with attraction on one side and repulsion on the other; second, utilizing complementary air gap relationships to achieve slope compensation between the attraction curve and the repulsion curve; and third, using thrust difference and thrust fluctuation rate as indicators to match structural parameters, excitation parameters, and repulsion magnetic source parameters, thereby simultaneously achieving bidirectional motion control and force-displacement nonlinear suppression.

[0068] To verify the effect of the attraction-repulsion synergistic drive and complementary air gap compensation method in this invention on suppressing the nonlinearity of the output force, a simulation model of an opposed reluctance linear actuator was established. In the simulation, the soft magnetic material, geometric dimensions, excitation method, and modeling boundary conditions were kept consistent; only the compensation reference air gap was changed. Calculate different The curve showing the change of total output force with mover displacement under certain conditions.

[0069] In this embodiment, when the mover is located at the geometric center of the two stators, the air gap lengths on both sides are equal, serving as compensation reference air gaps. When the mover is displaced along the axis of motion, the air gap on one side decreases, while the air gap on the other side increases by the same amount. Based on this complementary air gap relationship, the output force on the attraction side and the output force on the repulsion side are mapped to the same displacement coordinate and superimposed to obtain the total output force under the combined attraction and repulsion effect:

[0070] Figure 7 Different compensation reference air gaps are given The curve showing the total thrust versus displacement. Figure 7 It can be seen that, with As the air gap length increases, the overall thrust tends to decrease. This is because an increase in air gap length leads to an increase in air gap magnetic reluctance, which reduces the main magnetic flux of the magnetic circuit under fixed excitation conditions, thus reducing the output thrust. Simultaneously, different... The slope and fluctuation of the thrust curves are not the same under the same conditions, indicating that the compensation reference air gap is being compensated. It will directly affect the force-displacement characteristics after the superposition of attractive and repulsive forces.

[0071] different The thrust difference and thrust fluctuation rate are shown in Table 1:

[0072] Table 1 As shown in Table 1, when When the thrust difference is increased from 1.0 mm to 2.0 mm, the thrust difference decreases from 450.40 N to 276.98 N, and the thrust fluctuation rate decreases from 17.9% to 15.5%. This indicates that appropriately increasing the compensation reference gap can weaken the influence of the steep change in attractive force in the small gap range on the total thrust curve, making the output force change more smoothly with displacement.

[0073] when When the gap is further increased to 2.5 mm and 3.0 mm, the thrust difference is 253.02 N and 255.83 N, respectively, but the thrust fluctuation rate increases to 16.8% and 20.5%, respectively. This indicates that a larger compensation reference gap is not necessarily better. When the value is too large, the overall magnetic resistance increases, the total thrust level decreases, and the proportion of repulsive side fluctuations in the resultant force increases, resulting in an increase in thrust fluctuation rate.

[0074] Therefore, by appropriately selecting the compensation reference air gap This invention achieves a trade-off between output thrust level and thrust fluctuation suppression, resulting in a smoother total thrust-displacement curve after the superposition of attractive and repulsive forces. This embodiment demonstrates that the present invention can reduce the force-displacement nonlinearity caused by air gap changes in reluctance linear actuators through complementary air gaps and a combined attractive-repulsive mechanism, thereby improving the consistency and controllability of output force during short-stroke drive processes.

[0075] Reference Figure 8 As shown, under the same current conditions, when the movers of both the CI type and the opposed structure of this invention move within a range of 0.7 mm, the thrust curves are as follows: Figure 8 As shown, According to the formula

[0076]

[0077] Referring to Table 2, which shows a comparison of the thrust curves of the CI-type reluctance linear actuator and the opposed-type reluctance linear actuator,

[0078] Table 2 The maximum output electromagnetic force of the CI type is 551.72N, and the minimum is 58.31N; the maximum output electromagnetic force of the opposed type is 560.46N, and the minimum is 281.10N. Based on these calculations, the thrust fluctuation is 80.9% for the CI type and 33.2% for the opposed type. The opposed type reluctance linear actuator of this invention effectively reduces the output thrust fluctuation through changes in topology.

[0079] This invention is not limited to the above-described embodiments. Without departing from the spirit and essence of this invention, those skilled in the art can make equivalent substitutions or improvements to the sequence of steps, parameter settings, and specific implementation forms, all of which should fall within the protection scope of the claims of this invention.

Claims

1. A counter-type reluctance linear actuator with attraction-repulsion cooperative driving and thrust nonlinear suppression, characterized in that, It includes a first stator (1), a second stator (3), a mover (5), a first stator excitation coil (2), and a second stator excitation coil (4). The first stator (1) and the second stator (3) are arranged opposite each other along the direction of motion of the mover (5). The mover (5) is located between the first stator (1) and the second stator (3) and moves in a short-stroke straight line along the line connecting the first stator (1) and the second stator (3). A first working air gap is formed between the mover (5) and the first stator (1), and a second working air gap is formed between the mover (5) and the second stator (3). The first stator excitation coil (2) and the second stator excitation coil (4) are wound on the first stator (1) and the second stator (3) respectively. When energized, in the same direction of motion, the magnetic circuit between one stator and the mover (5) generates an attractive force pointing in the direction of motion, and the magnetic circuit between the other stator and the mover (5) generates a repulsive force in the same direction. The attractive force and the repulsive force together constitute the effective output force of the mover (5).

2. The opposed reluctance linear actuator with attraction-repulsion synergistic drive and thrust nonlinear suppression according to claim 1, characterized in that, The mover (5) is a permanent magnet magnetic source mover assembly or a dual-winding excitation coil mover assembly, wherein, When the mover (5) is a permanent magnet source mover assembly, the source is a permanent magnet structure and the permanent magnet is located at the center point of the assembly; When the mover (5) is a double-winding excitation coil mover assembly, the double-winding excitation coil mover assembly is composed of two independent excitation coils on the left and right sides forming a polarity configuration winding structure.

3. The opposed reluctance linear actuator with attraction-repulsion synergistic drive and thrust nonlinear suppression according to claim 2, characterized in that, Let the direction of motion of the mover (5) be the x-axis, and x=0 when the mover (5) is in the intermediate reference position. The reference air gap is the compensation reference air gap. The first working air gap is The second working air gap is When the mover (5) is displaced by x, the air gaps on both sides satisfy: When the mover (5) moves, the air gap on one side increases and the air gap on the other side decreases. The two air gaps have a complementary relationship. In order to avoid the mover (5) from contacting the stator, the air gaps on both sides must satisfy: In the formula, Indicates the minimum permissible working air gap. This indicates the maximum permissible working air gap.

4. The opposed reluctance linear actuator with attraction-repulsion synergistic drive and thrust nonlinear suppression according to claim 3, characterized in that, When the mover (5) moves in the forward direction, the stator on the forward side is the attraction side and the stator on the reverse side is the repulsion side. The attraction and repulsion forces are superimposed in the same direction, which drives the mover (5) to move in the forward direction. When the mover (5) moves in the opposite direction, the attraction / repulsion states of the stators on both sides are interchanged, and the attraction and repulsion forces are superimposed in the same direction to drive the mover (5) to move in the opposite direction.

5. The opposed reluctance linear actuator with attraction-repulsion synergistic drive and thrust nonlinear suppression according to claim 4, characterized in that, With the target motion direction as the positive direction, the effective output force of the actuator is the superposition of the attractive and repulsive forces in the same direction. Unlike the opposed magnetoresistive actuator with differential output from both sides, the effective output force is not the difference between the attractive forces on both sides.

6. A thrust nonlinearity suppression design method for an opposed reluctance linear actuator, based on the opposed reluctance linear actuator with attraction-repulsion cooperative drive and thrust nonlinearity suppression as described in any one of claims 1-5, characterized in that, Includes the following steps: S1. Construct the basic structure of the opposing magnetic reluctance linear actuator with attraction-repulsion cooperative drive, set up the first stator (1) and the second stator (3) opposite each other along the motion direction of the mover, and place the mover (5) between the two stators so that the mover (5) forms a first working air gap with the first stator (1) and a second working air gap with the second stator (3); S2. Establish an attraction-repulsion coordinated output force model. Set that when the mover (5) moves in one direction, one side of the magnetic circuit generates an attraction force pointing in the direction of motion, and the other side of the magnetic circuit generates a repulsion force in the same direction. The superposition value of the attraction and repulsion forces is used as the effective output force of the actuator. S3. Based on the complementary change relationship between the working air gaps on both sides and the displacement of the mover (5), adjust the compensation reference air gap, pole area, excitation state and repulsion magnetic source parameters to reduce the gradient of the output force change with displacement, so that the output force curve tends to be flat and the nonlinear suppression of thrust is achieved.

7. The thrust nonlinearity suppression design method for the opposed reluctance linear actuator according to claim 6, characterized in that, In S2, the output force on the attraction side and repulsive side output force They are represented as follows: In the formula, , These represent the number of turns in the coils on the attraction and repulsion sides, respectively. , These represent the magnetizing currents on the attraction and repulsion sides, respectively. , These represent the effective polar areas on both sides; BH Indicates the magnetization curve of a soft magnetic material; Indicates the magnetic source parameters that generate the repulsive effect; , These represent the electromagnetic force functions on the attracting and repelling sides, respectively.

8. The thrust nonlinearity suppression design method for the opposed reluctance linear actuator according to claim 7, characterized in that, In S2, taking the target motion direction as the positive direction, the effective output force of the actuator satisfies: In the formula, The effective output force of the mover (5) along the target direction, the output force of the ordinary double-sided attraction differential output opposed reluctance actuator satisfies: In the formula, , These represent the attraction forces on the left and right sides, respectively, and represent the differential output of the attraction forces on the left and right sides.

9. The thrust nonlinearity suppression design method for the opposed reluctance linear actuator according to claim 8, characterized in that, In S3, the gradient of the output force as a function of displacement satisfies: In the formula, This represents the gradient of the output force as a function of displacement. This represents the partial derivative of the attractive force with respect to the working air gap on the attractive side; This represents the partial derivative of the repulsive force with respect to the working air gap on the repulsive side.

10. The thrust nonlinearity suppression design method for the opposed reluctance linear actuator according to claim 9, characterized in that, In S3, thrust differential is used. and thrust volatility As an evaluation index for the stability of output force, both satisfy the following: In the formula, , , These represent the maximum, minimum, and average output force within the target stroke, respectively. or The smaller the value, the smoother the output force changes with displacement.

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