A position sensorless predictive control method for linear oscillatory motor

Abstract

The application discloses a kind of linear oscillation motor's position sensorless prediction control method, acquisition stator voltage and stator current, using fractional order sliding mode observer obtains back electromotive force estimation value, constructs displacement directional synchronous rotating coordinate system by orthogonal signal generation and coordinate transformation;According to back electromotive force shaft component and operating angular frequency, the amplitude estimation value of moving displacement is calculated, the shaft current reference value is set to zero, and the shaft current reference value is generated by stroke outer ring;Determine inverter output control quantity based on current prediction model and generate PWM signal to drive motor.The application does not need position sensor and back electromotive force pure integration, can reduce integral drift and phase lag, realize the decoupling adjustment of resonant state and moving stroke, improve displacement estimation precision and stroke control performance.

Description

Technical Field

[0001] This invention relates to the technical field of sensorless control of linear oscillating motors, and in particular to a sensorless predictive control method for linear oscillating motors. Background Technology

[0002] Linear oscillating motors can directly generate reciprocating linear motion, eliminating the need for traditional intermediate transmission mechanisms such as crankshafts and connecting rods. They offer advantages such as compact structure, low friction loss, and high efficiency, and are widely used in reciprocating motion drive applications such as linear compressors and Stirling refrigerators. Since the mover of a linear oscillating motor is usually directly connected to the piston or load mechanism, excessive mover stroke can easily cause cylinder collision, mechanical impact, or structural damage. Therefore, closed-loop control of the mover stroke is necessary. Simultaneously, linear oscillating motors exhibit significant resonant operating characteristics; operating them near the mechanical resonance point helps improve system efficiency.

[0003] Existing sensorless control methods for linear oscillating motors typically estimate the back electromotive force (EMF) based on the voltage equation and obtain the mover displacement information through integration. However, the back EMF integration method is susceptible to parameter errors, sampling noise, and DC bias, resulting in issues such as integral drift and phase lag, which affect the accuracy of mover displacement estimation. On the other hand, existing resonant frequency tracking and stroke control methods usually require separate setups for phase detection, frequency adjustment, stroke closed-loop control, and current control. These control variables have a certain degree of coupling, making the system structure relatively complex, and the dynamic response speed under conditions such as start-up, variable stroke, or load changes still needs improvement. Summary of the Invention

[0004] The purpose of this invention is to provide a sensorless predictive control method for linear oscillating motors, which solves the problems in existing linear oscillating motor control, such as displacement estimation easily causing integral drift and phase lag, and the coupling between resonant frequency tracking and mover stroke adjustment leading to limited system dynamic performance.

[0005] To achieve the above objectives, the technical solution provided by this invention is: a sensorless predictive control method for a linear oscillating motor, comprising the following steps:

[0006] Step S1: Collect the stator voltage and stator current of the linear oscillating motor, construct a fractional sliding mode observer based on the voltage equation of the linear oscillating motor to observe the back electromotive force and obtain the estimated value of the back electromotive force;

[0007] Step S2: Generate orthogonal signals from the estimated values ​​of stator voltage, stator current, and back electromotive force to construct a virtual two-phase static circuit. A coordinate system is established, and coordinate transformations are performed based on the synchronous rotation angle to construct the synchronous rotation. Using a coordinate system, the estimated values ​​of the stator voltage, stator current, and back electromotive force are obtained respectively. Axial components and Axial components;

[0008] Step S3: Extract the operating angular frequency based on the stator current, and based on the estimated back electromotive force value. The axis component adjusts the synchronous rotation angle so that the The axial components converge to zero to form a vector with respect to the displacement vector of the mover. Displacement orientation synchronous rotation of axis orientation reference Coordinate system;

[0009] Step S4: Synchronously rotate in the displacement orientation In the coordinate system, based on the estimated back electromotive force... The estimated value of the mover displacement amplitude is calculated using the shaft component and the operating angular frequency.

[0010] Step S5: Synchronously rotate in the displacement orientation coordinate system, The shaft current reference value is set to zero, and a value is generated based on the error between the given value of the mover displacement amplitude and the estimated value of the mover displacement amplitude. Shaft current reference value;

[0011] Step S6: Synchronous rotation based on the displacement orientation The current prediction model in the coordinate system, based on the above Shaft current reference value Shaft current reference value and the stator current Axial components and The axis component determines the output control quantity of the inverter used to drive the linear oscillating motor;

[0012] Step S7: Generate a PWM signal based on the output control quantity of the inverter to drive the linear oscillating motor to achieve sensorless predictive control.

[0013] Furthermore, in step S1, the voltage equation of the linear oscillating motor is:

[0014] ;

[0015] In the formula, Stator voltage, For stator current, It is the back electromotive force. For stator resistance, For stator inductance, For time.

[0016] Furthermore, in step S1, the control law of the fractional-order sliding mode observer is:

[0017] ;

[0018] ;

[0019] ;

[0020] In the formula, This is the output of the sliding mode observer. For equivalent control items, To switch control items, For current observation error, For sliding surface, For fractional differential operators, This is an adjustable gain parameter;

[0021] The back electromotive force estimate is obtained according to the following relationship:

[0022] ;

[0023] In the formula, This is the estimated value of the back electromotive force.

[0024] Furthermore, in step S2, for any single-phase electrical quantity among the stator voltage, stator current, or back electromotive force estimate... The orthogonal signal generation satisfies:

[0025] ;

[0026] ;

[0027] ;

[0028] In the formula, and These are the single-phase electrical quantities. In virtual two-phase stillness In the coordinate system Axial components and Axial components, To and Orthogonal signal generation results The imaginary unit satisfies , For virtual two-phase static Spatial vectors in a coordinate system;

[0029] The coordinate transformation satisfies:

[0030] ;

[0031] ;

[0032] In the formula, For the virtual two-phase static Spatial vectors in a coordinate system Synchronous rotation obtained after coordinate transformation Spatial vectors in a coordinate system It is a natural exponential function. The imaginary unit, For synchronous rotation angle, and The space vectors are respectively In synchronous rotation In the coordinate system Axial components and Axial components.

[0033] Furthermore, in step S3, the operating angular frequency extracted from the stator current is used as the feedforward for updating the synchronous rotation angle, and the back electromotive force estimate is used as the feedforward. Axial components Constructing phase error signal Based on the operating angular frequency and the phase error signal Update the synchronous rotation angle so that the back electromotive force estimate is... The axial components converge to zero to form the displacement-oriented synchronous rotation. Coordinate system; wherein, in steps S2 and S3, the orthogonal signal generation can be implemented using a second-order generalized integrator; the operating angular frequency can be extracted by a second-order generalized integrator-frequency-locked loop based on stator current; the synchronous rotation angle can be estimated by a second-order generalized integrator-phase-locked loop based on the back electromotive force. The axial component is obtained by closed-loop adjustment.

[0034] Furthermore, in step S4, during the displacement-oriented synchronous rotation... In the coordinate system, the following conditions are met:

[0035] ;

[0036] ;

[0037] In the formula, The back electromotive force estimate Axial components, The back electromotive force estimate Axial components, This is the electromagnetic thrust coefficient. For the operating angular frequency, This represents the amplitude of the mover displacement.

[0038] The estimated value of the mover displacement amplitude is calculated according to the following relationship:

[0039] ;

[0040] In the formula, This is the estimated value of the mover displacement amplitude.

[0041] Furthermore, in step S5, during the displacement-oriented synchronous rotation... In the coordinate system, the following conditions are met:

[0042] ;

[0043] ;

[0044] In the formula, For stator current Axial components, For stator current Axial components, For equivalent spring stiffness, This is the electromagnetic thrust coefficient. For the equivalent mass of the mover, This is the equivalent damping coefficient. The magnitude of the mover displacement is given by the stator current. When the shaft component approaches zero, the linear oscillating motor approaches a mechanical resonance operating state, and the stator current... The axial component varies with the displacement amplitude of the mover; Shaft current reference value satisfy The Shaft current reference value It is generated by the outer loop controller based on the error between the given value of the mover displacement amplitude and the estimated value of the mover displacement amplitude.

[0045] Furthermore, in step S6, the current prediction model is synchronous rotation. A discrete current prediction model in a coordinate system is used to predict the output control quantity of a candidate inverter. Axial components and Axial components and according to , and Shaft current reference value , Shaft current reference value The tracking error between the two values ​​determines the inverter output control quantity.

[0046] Furthermore, in step S6, an effective voltage vector and a zero voltage vector are applied in combination within one control cycle, and the current tracking error cost function is minimized. Solve for the duty cycle of the effective voltage vector; the current tracking error cost function is: The cost function is evaluated for the combination of positive effective voltage vector and zero voltage vector and the combination of negative effective voltage vector and zero voltage vector respectively, and the voltage vector combination with the smaller cost function value is selected as the inverter output control quantity for the current control cycle.

[0047] Furthermore, in step S7, the inverter is an H-bridge inverter, and the PWM signal determines the switching state of the H-bridge inverter according to the output control quantity, ultimately completing the sensorless predictive control of the linear oscillating motor.

[0048] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0049] 1. This invention employs a fractional-order sliding mode observer to observe the back electromotive force (EMF) of a linear oscillating motor, which helps improve the accuracy of back EMF estimation; in displacement-oriented synchronous rotation... In the coordinate system, based on the estimated value of the back electromotive force The estimated value of the mover displacement amplitude is directly calculated from the shaft component and the operating angular frequency, without the need for pure integration of the back electromotive force. This avoids integral drift, initial value sensitivity and phase lag caused by pure integration, and improves the accuracy of mover displacement amplitude estimation under sensorless conditions.

[0050] 2. This invention extends the estimated values ​​of single-phase stator voltage, stator current, and back electromotive force of a linear oscillating motor to a virtual two-phase stationary state through orthogonal signal generation. Coordinate system, and further transformed to synchronous rotation A coordinate system enables the electrical quantities of a linear oscillating motor to be analyzed and controlled in the form of spatial vectors; this allows for displacement-oriented synchronous rotation. In the coordinate system, the mechanical resonance state adjustment and the mover stroke control are respectively transformed into Axis current components and Adjusting the shaft current component reduces the coupling between mechanical resonance state adjustment and mover stroke control, and simplifies the control structure.

[0051] 3. This invention employs displacement-oriented synchronous rotation. Discrete current prediction model in coordinate system, predicting based on candidate inverter output control quantity. Axial components and The axis component is determined, and the inverter output control quantity is determined based on the current tracking error cost function, so that... Axial components and The shaft components track their respective reference values, thereby achieving mechanical resonance state adjustment and mover stroke closed-loop control. Attached Figure Description

[0052] Figure 1 This is a control block diagram provided for an embodiment of the present invention.

[0053] Figure 2 Displacement-oriented synchronous rotation provided in the embodiments of the present invention A schematic diagram of the vector relationships in a coordinate system.

[0054] Figure 3 This is a schematic diagram illustrating the sensorless predictive control effect of a linear oscillating motor provided in an embodiment of the present invention. Detailed Implementation

[0055] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. The following embodiments are used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Without departing from the concept of the present invention, those skilled in the art can make equivalent substitutions for the observer form, orthogonal signal generation method, current prediction model or inverter topology.

[0056] This embodiment discloses a sensorless predictive control method for a linear oscillating motor. For example... Figure 1 As shown, SOGI-FLL represents a second-order generalized integrator-frequency-locked loop, used to extract the operating angular frequency from the stator current; SOGI-PLL represents a second-order generalized integrator-phase-locked loop, used to extract the operating angular frequency from the back electromotive force estimate. Shaft component adjustment synchronizes rotation angle; PARK represents the coordinate transformation stage, used to bring the virtual two-phase stationary... Electrical quantity transformation in coordinate system to synchronous rotation Coordinate system; Dual-vector predictive control and duty cycle optimization: The dual-vector model predicts current control and duty cycle optimization, which is used to determine the inverter output control quantity based on the current prediction result and the cost function.

[0057] Specifically, the method includes the following steps:

[0058] Step S1: Collect the stator voltage and stator current of the linear oscillating motor, and construct a fractional sliding mode observer based on the voltage equation of the linear oscillating motor to observe the back electromotive force.

[0059] The voltage equation for a linear oscillating motor is:

[0060] ;

[0061] In the formula, Stator voltage, For stator current, It is the back electromotive force. For stator resistance, For stator inductance, For time.

[0062] In this embodiment, the control law of the fractional-order sliding mode observer is:

[0063] ;

[0064] ;

[0065] ;

[0066] In the formula, This is the output of the sliding mode observer. For equivalent control items, To switch control items, For current observation error, For sliding surface, For fractional differential operators, This is an adjustable gain parameter.

[0067] The back electromotive force estimate is obtained according to the following relationship:

[0068] ;

[0069] In the formula, This is the estimated value of the back electromotive force.

[0070] Therefore, the controller can obtain the back electromotive force estimate based on the collected stator voltage and stator current without setting up a position sensor, providing input for subsequent orthogonal signal generation, displacement orientation and mover displacement amplitude estimation.

[0071] Step S2: Generate orthogonal signals from the estimated values ​​of stator voltage, stator current, and back electromotive force to construct a virtual two-phase static circuit. A coordinate system is established, and coordinate transformations are performed based on the synchronous rotation angle to construct the synchronous rotation. Coordinate system.

[0072] For any single-phase physical quantity in the stator voltage, stator current, or back electromotive force estimate Treat it as a virtual two-phase static In the coordinate system The axis component is obtained by generating orthogonal signals to it. Axial components, i.e.:

[0073] ;

[0074] ;

[0075] ;

[0076] In the formula, and These are the single-phase electrical quantities. In virtual two-phase stillness In the coordinate system Axial components and Axial components, To and Orthogonal signal generation results The imaginary unit satisfies , For virtual two-phase static Spatial vectors in a coordinate system.

[0077] Subsequently, based on the synchronous rotation angle Perform coordinate transformation on the virtual space vector to obtain synchronous rotation. Spatial vectors in a coordinate system:

[0078] ;

[0079] ;

[0080] In the formula, For the virtual two-phase static Spatial vectors in a coordinate system Synchronous rotation obtained after coordinate transformation Spatial vectors in a coordinate system It is a natural exponential function. The imaginary unit, For synchronous rotation angle, and The space vectors are respectively In synchronous rotation In the coordinate system Axial components and Axial components.

[0081] Through the above-mentioned orthogonal signal generation and coordinate transformation, the single-phase electrical quantities of the linear oscillating motor are expanded into a space vector form, enabling the stator voltage, stator current, and back electromotive force estimates to be obtained during synchronous rotation. Analysis and control are performed in a coordinate system.

[0082] Step S3: Extract the operating angular frequency based on the stator current, and estimate the back electromotive force. The shaft component adjusts the synchronous rotation angle to make the back electromotive force estimate... The axial components converge to zero, resulting in displacement-oriented synchronous rotation. Coordinate system.

[0083] In this embodiment, a second-order generalized integrator-frequency-locked loop is used to extract the operating angular frequency from the stator current. and the operating angular frequency As a feedforward for the synchronous rotation angle update. Simultaneously, using the back electromotive force estimate. Axial components Constructing phase error signal According to the operating angular frequency and the phase error signal Update synchronous rotation angle , making the back electromotive force estimate Axial components It converges to zero.

[0084] like Figure 2 As shown, when When it converges to zero, the back electromotive force vector is located at Axial direction. Since the back electromotive force is proportional to the mover velocity, and in simple harmonic motion the mover velocity leads the mover displacement. Therefore, when the back electromotive force vector is located at In the axial direction, The shaft and the displacement vector of the mover are aligned, thus forming a shape with the displacement vector of the mover as the center. Displacement orientation synchronous rotation of axis orientation reference Coordinate system.

[0085] Step S4, synchronous rotation in displacement orientation In the coordinate system, based on the estimated value of the back electromotive force The estimated value of the mover displacement amplitude is calculated using the shaft component and the operating angular frequency.

[0086] The displacement-oriented synchronous rotation In the coordinate system, the following conditions are met:

[0087] ;

[0088] ;

[0089] In the formula, The back electromotive force estimate Axial components, The back electromotive force estimate Axial components, This is the electromagnetic thrust coefficient. For the operating angular frequency, This represents the displacement amplitude of the mover.

[0090] The estimated value of the mover displacement amplitude is calculated according to the following relationship:

[0091] ;

[0092] In the formula, This is the estimated value of the mover displacement amplitude.

[0093] As can be seen from the above relationship, this embodiment does not require pure integration of the back electromotive force to obtain the estimated value of the mover displacement amplitude, thereby avoiding the problems of integral drift, initial value sensitivity and phase lag caused by the pure integration stage in the traditional back electromotive force integration method, and improving the accuracy of mover displacement amplitude estimation under the condition of no position sensor.

[0094] Step S5, synchronous rotation in displacement orientation In the coordinate system, generated based on the estimated displacement amplitude of the mover. Shaft current reference value and Shaft current reference value.

[0095] The displacement-oriented synchronous rotation In the coordinate system, the electromechanical coupling relationship of the linear oscillating motor satisfies:

[0096] ;

[0097] ;

[0098] In the formula, For stator current Axial components, For stator current Axial components, For equivalent spring stiffness, This is the electromagnetic thrust coefficient. For the equivalent mass of the mover, This is the equivalent damping coefficient. This represents the amplitude of the mover displacement. From the above relationship, it can be seen that... Axial components and Related. When When approaching zero, As the linear oscillating motor approaches zero, it approaches a state of mechanical resonance operation. Axial components It is related to the amplitude of the mover displacement, so it can be adjusted Shaft component enables mover stroke control.

[0099] In this embodiment, Shaft current reference value Set as Set the displacement amplitude of the mover to a given value. With the estimated value of the mover displacement amplitude By comparison, the travel error is obtained. :

[0100] ;

[0101] The travel error After processing by the outer loop controller, the following is generated: Shaft current reference value In one embodiment, the outer loop controller is a PI controller. Shaft current reference value It can be represented as:

[0102] ;

[0103] In the formula, This is the proportional coefficient of the outer loop controller. This represents the integral coefficient of the outer loop controller.

[0104] Through the above methods The shaft current reference value is used to bring the linear oscillating motor closer to its mechanical resonance operating state. The shaft current reference value is used to achieve closed-loop control of the mover displacement amplitude, thereby unifying the resonant state adjustment and mover stroke control into a single function. The issue of adjusting the axial components.

[0105] Step S6, synchronous rotation based on displacement orientation Current prediction model in coordinate system, based on Shaft current reference value Shaft current reference value and stator current Axial components and The shaft component determines the inverter output control quantity.

[0106] Displacement-oriented synchronous rotation In the coordinate system, the current prediction model is a discrete current prediction model. The forward Euler method is used, with a sampling period of... hour, Moment shaft current and The predicted shaft current value can be expressed as:

[0107] ;

[0108] In the formula, and They are respectively Stator current at any time Axial components and Axial components, and The output voltage of the candidate inverters are respectively at shaft and Components on the axis, and The back electromotive force estimates are respectively in shaft and Components on the axis, The sampling period.

[0109] Model predictive current control predicts current output based on candidate inverter output control values. Axial components and Axial components A current tracking error cost function is constructed based on the error between the predicted current and the current reference value. :

[0110] ;

[0111] In the formula, For the predicted Axial components, For the predicted Axial components.

[0112] In this embodiment, the model predictive current control adopts a dual-vector modulation method, which combines an effective voltage vector and a zero voltage vector within one control cycle, and solves the duty cycle of the effective voltage vector by minimizing the current tracking error cost function.

[0113] Let the ratio of the effective voltage vector's action time to the control cycle be the duty cycle. Then the predicted current can be expressed as a linear function of the duty cycle:

[0114] ;

[0115] ;

[0116] In the formula, and When zero voltage vector is applied Predicted shaft current and Predicted shaft current value and The difference between the applied effective voltage vector and the applied zero voltage vector is respectively caused by the application of the effective voltage vector. shaft current increment and Axis current increment.

[0117] Because the predicted current is related to the duty cycle The relationship is linear, therefore the cost function Regarding duty cycle Let it be a quadratic function. The analytical solution for the duty cycle of the effective voltage vector action can be obtained:

[0118] ;

[0119] In practical applications, Limited to Within the specified range. For inverters used to drive linear oscillating motors, cost functions are evaluated for the combinations of positive effective voltage vectors and zero voltage vectors, and the combinations of negative effective voltage vectors and zero voltage vectors, respectively. The voltage vector combination with the smaller cost function value is selected as the inverter output control quantity for the current control cycle.

[0120] Step S7: Generate a PWM signal based on the inverter output control quantity to drive the linear oscillating motor to achieve sensorless predictive control.

[0121] In this embodiment, the inverter is an H-bridge inverter. The controller determines the switching state of the H-bridge inverter based on the inverter output control quantity obtained in step S6, and generates a corresponding PWM signal to enable the H-bridge inverter to apply the required terminal voltage to the linear oscillating motor.

[0122] The linear oscillating motor operates under the action of the PWM signal, and through the aforementioned back EMF observation, orthogonal signal generation, displacement orientation, mover displacement amplitude estimation, stroke outer loop control, and model predictive current control processes, it achieves resonance state adjustment and mover stroke closed loop control under sensorless conditions.

[0123] like Figure 3 As shown, in one embodiment, the setpoint for the mover displacement amplitude is set to 5 mm, and the initial operating frequency of the linear oscillating motor is approximately 15 Hz. After startup, The shaft current gradually stabilized at approximately 0.21 A. The shaft current approaches zero, the operating frequency stabilizes at approximately 19.2 Hz, and the mover displacement amplitude approaches and stabilizes around 5 mm. During the startup process of the linear oscillating motor, the method described in this embodiment can obtain an estimated value of the mover displacement amplitude based on the back electromotive force estimate and the operating angular frequency, and then... Shaft current reference value and The shaft current reference value is used to adjust the mechanical resonance state and the mover stroke, respectively, so that the mover displacement amplitude tracks the given value, and at the same time... The shaft current approaches zero. Therefore, this embodiment enables predictive control of a linear oscillating motor without the need for position sensors.

[0124] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. For those skilled in the art, equivalent substitutions or modifications can be made to the specific parameters of the fractional-order sliding mode observer, the orthogonal signal generation method, the outer loop controller form, the current prediction model discretization method, and the inverter topology without departing from the concept of the present invention. All such equivalent substitutions or modifications should be included within the scope of protection of the present invention.

Claims

1. A sensorless predictive control method for a linear oscillating motor, characterized in that, Includes the following steps: Step S1: Collect the stator voltage and stator current of the linear oscillating motor, construct a fractional sliding mode observer based on the voltage equation of the linear oscillating motor to observe the back electromotive force and obtain the estimated value of the back electromotive force; Step S2: Generate orthogonal signals from the estimated values ​​of stator voltage, stator current, and back electromotive force to construct a virtual two-phase static circuit. A coordinate system is established, and coordinate transformations are performed based on the synchronous rotation angle to construct the synchronous rotation. Using a coordinate system, the estimated values ​​of the stator voltage, stator current, and back electromotive force are obtained respectively. Axial components and Axial components; Step S3: Extract the operating angular frequency based on the stator current, and based on the estimated back electromotive force value. The axis component adjusts the synchronous rotation angle so that the The axial components converge to zero to form a vector with respect to the displacement vector of the mover. Displacement orientation synchronous rotation of axis orientation reference Coordinate system; Step S4: Synchronously rotate in the displacement orientation In the coordinate system, based on the estimated back electromotive force... The estimated value of the mover displacement amplitude is calculated using the shaft component and the operating angular frequency. Step S5: Synchronously rotate in the displacement orientation coordinate system, The shaft current reference value is set to zero, and a value is generated based on the error between the given value of the mover displacement amplitude and the estimated value of the mover displacement amplitude. Shaft current reference value; Step S6: Synchronous rotation based on the displacement orientation The current prediction model in the coordinate system, based on the above Shaft current reference value Shaft current reference value and the stator current Axial components and The axis component determines the output control quantity of the inverter used to drive the linear oscillating motor; Step S7: Generate a PWM signal based on the output control quantity of the inverter to drive the linear oscillating motor to achieve sensorless predictive control.

2. The sensorless predictive control method for a linear oscillating motor according to claim 1, characterized in that, In step S1, the voltage equation of the linear oscillating motor is: ； In the formula, Stator voltage, For stator current, It is the back electromotive force. For stator resistance, For stator inductance, For time.

3. The sensorless predictive control method for a linear oscillating motor according to claim 2, characterized in that, In step S1, the control law of the fractional-order sliding mode observer is: ； ； ； In the formula, This is the output of the sliding mode observer. For equivalent control items, To switch control items, For current observation error, For sliding surface, For fractional differential operators, This is an adjustable gain parameter; The back electromotive force estimate is obtained according to the following relationship: ； In the formula, This is the estimated value of the back electromotive force.

4. The sensorless predictive control method for a linear oscillating motor according to claim 3, characterized in that, In step S2, for any single-phase electrical quantity among the estimated values ​​of stator voltage, stator current, or back electromotive force... The orthogonal signal generation satisfies: ； ； ； In the formula, and These are the single-phase electrical quantities. In virtual two-phase stillness In the coordinate system Axial components and Axial components, To and Orthogonal signal generation results The imaginary unit satisfies , For virtual two-phase static Spatial vectors in a coordinate system; The coordinate transformation satisfies: ； ； In the formula, For the virtual two-phase static Spatial vectors in a coordinate system Synchronous rotation obtained after coordinate transformation Spatial vectors in a coordinate system It is a natural exponential function. The imaginary unit, For synchronous rotation angle, and The space vectors are respectively In synchronous rotation In the coordinate system Axial components and Axial components.

5. The sensorless predictive control method for a linear oscillating motor according to claim 4, characterized in that, In step S3, the operating angular frequency extracted from the stator current is used as the feedforward for updating the synchronous rotation angle, and the back electromotive force estimate is used as the feedforward. Axial components Constructing phase error signal Based on the operating angular frequency and the phase error signal Update the synchronous rotation angle so that the back electromotive force estimate is... The axial components converge to zero to form the displacement-oriented synchronous rotation. Coordinate system; wherein, in steps S2 and S3, the orthogonal signal generation can be implemented using a second-order generalized integrator; the operating angular frequency can be extracted by a second-order generalized integrator-frequency-locked loop based on stator current; the synchronous rotation angle can be estimated by a second-order generalized integrator-phase-locked loop based on the back electromotive force. The shaft component is obtained by closed-loop adjustment.

6. The sensorless predictive control method for a linear oscillating motor according to claim 5, characterized in that, In step S4, during the displacement-oriented synchronous rotation In the coordinate system, the following conditions are met: ； ； In the formula, The back electromotive force estimate Axial components, The back electromotive force estimate Axial components, This is the electromagnetic thrust coefficient. For the operating angular frequency, This represents the amplitude of the mover displacement. The estimated value of the mover displacement amplitude is calculated according to the following relationship: ； In the formula, This is the estimated value of the mover displacement amplitude.

7. The sensorless predictive control method for a linear oscillating motor according to claim 6, characterized in that, In step S5, during the displacement-oriented synchronous rotation In the coordinate system, the following conditions are met: ； ； In the formula, For stator current Axial components, For stator current Axial components, For equivalent spring stiffness, This is the electromagnetic thrust coefficient. For the equivalent mass of the mover, This is the equivalent damping coefficient. The magnitude of the mover displacement is given by the stator current. When the shaft component approaches zero, the linear oscillating motor approaches a mechanical resonance operating state, and the stator current... The axial component varies with the displacement amplitude of the mover; Shaft current reference value satisfy The Shaft current reference value It is generated by the outer loop controller based on the error between the given value of the mover displacement amplitude and the estimated value of the mover displacement amplitude.

8. The sensorless predictive control method for a linear oscillating motor according to claim 7, characterized in that, In step S6, the current prediction model is synchronous rotation. A discrete current prediction model in a coordinate system is used to predict the output control quantity of a candidate inverter. Axial components and Axial components and according to , and Shaft current reference value , Shaft current reference value The tracking error between the two values ​​determines the inverter output control quantity.

9. A sensorless predictive control method for a linear oscillating motor according to claim 8, characterized in that, In step S6, an effective voltage vector and a zero voltage vector are applied in combination within one control cycle, and the current tracking error cost function is minimized. Solve for the duty cycle of the effective voltage vector; the current tracking error cost function is: The cost function is evaluated for the combination of positive effective voltage vector and zero voltage vector and the combination of negative effective voltage vector and zero voltage vector respectively, and the voltage vector combination with the smaller cost function value is selected as the inverter output control quantity for the current control cycle.

10. A sensorless predictive control method for a linear oscillating motor according to claim 9, characterized in that, In step S7, the inverter is an H-bridge inverter, and the PWM signal determines the switching state of the H-bridge inverter according to the output control quantity, thus completing the sensorless predictive control of the linear oscillating motor.

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