Linear motor control method based on feedforward adaptation and storage medium

Abstract

The invention discloses a linear motor control method based on feedforward adaptation and a storage medium, and relates to the technical field of motor control. The method comprises the following steps: determining a position error based on an actual position of the linear motor and a preset reference position, and determining an acceleration error based on an actual acceleration of the linear motor and a preset reference acceleration; a feed-forward parameter change rate is determined based on a preset adaptive formula and the reference speed, the reference acceleration and the acceleration error of the linear motor, a feed-forward control parameter is determined based on the feed-forward parameter change rate, and the adaptive formula is obtained by deducing an error kinetic equation of the linear motor through a Lyapunov stability criterion; determining a feed-forward control quantity based on the feed-forward control parameter, the reference speed and the reference acceleration, determining a feedback control quantity based on the position error, and determining a total control quantity according to the feed-forward control quantity and the feedback control quantity; and driving the linear motor to move according to the total control quantity.

Description

A feedforward adaptive linear motor control method and storage medium Technical Field

[0001] This application relates to the field of motor control technology, and in particular to a linear motor control method and storage medium based on feedforward adaptive control. Background Technology

[0002] In the field of ultra-precision motion control, suspension guidance systems based on the principle of gas lubrication have become the core motion carriers for high-precision equipment such as high-end lithography wafer stages and spacecraft inertial component testing platforms, thanks to their nanometer-level motion resolution, near-zero frictional damping characteristics, and excellent vibration suppression capabilities. Permanent magnet synchronous direct drive linear motors (PMSMs), as the power execution units of such systems, directly determine the positioning accuracy and trajectory tracking performance of the entire motion system through their dynamic response characteristics and servo control quality.

[0003] In existing technologies, the stator dynamic coupling mechanism is introduced into the control strategy of linear motors. While maintaining the original feedback control architecture, a dual-sided damping constraint mechanism is used to achieve coordinated high-frequency micro-amplitude displacement response of the stator and mover, effectively shortening the motor's step response adjustment cycle. However, when linear motors meet the precise positioning requirements across the entire motion range in actual use, they are affected by dynamic disturbances caused by multi-physics coupling conditions (including but not limited to nonlinear attenuation of air film stiffness, enhanced stick-slip effect, temperature gradient deformation, and load mass changes). This results in significant drift of the supplementary parameters in the dynamic response characteristics of the dual-sided damping constraint mechanism, leading to problems such as compensation phase lag and limited disturbance suppression bandwidth, thus affecting the control accuracy and stability of the linear motor. Summary of the Invention

[0004] This application provides a feedforward adaptive linear motor control method and storage medium to improve the control architecture of the linear motor into a control architecture that integrates feedforward and feedback. The feedforward control parameters are updated in real time according to the actual motion parameters of the linear motor. The feedforward control parameters are used to compensate for the drift of inertia and damping coefficient caused by dynamic disturbance factors. This solves the problems of compensation phase lag and disturbance suppression bandwidth limitation caused by the prior art, and improves the control accuracy and stability of the linear motor.

[0005] In a first aspect, this application provides a feedforward adaptive linear motor control method, comprising: determining a position error based on the actual position of the linear motor and a preset reference position; determining an acceleration error based on the actual acceleration of the linear motor and a preset reference acceleration; determining a feedforward parameter change rate based on a preset adaptive formula and the reference speed, reference acceleration, and acceleration error of the linear motor; determining a feedforward control parameter based on the feedforward parameter change rate, wherein the adaptive formula is derived from the error dynamics equation of the linear motor using the Lyapunov stability criterion; determining a feedforward control quantity based on the feedforward control parameter, the reference speed, and the reference acceleration; determining a feedback control quantity based on the position error; determining a total control quantity based on the feedforward control quantity and the feedback control quantity; and driving the linear motor to move according to the total control quantity.

[0006] Secondly, this application provides a feedforward adaptive linear motor control device, comprising: a motion parameter determination module configured to determine a position error based on the actual position of the linear motor and a preset reference position, and to determine an acceleration error based on the actual acceleration of the linear motor and a preset reference acceleration; a feedforward parameter determination module configured to determine a feedforward parameter change rate based on a preset adaptive formula and the reference speed, reference acceleration, and acceleration error of the linear motor, and to determine a feedforward control parameter based on the feedforward parameter change rate, wherein the adaptive formula is derived from the error dynamics equation of the linear motor using the Lyapunov stability criterion; a control quantity determination module configured to determine a feedforward control quantity based on the feedforward control parameter, the reference speed, and the reference acceleration, to determine a feedback control quantity based on the position error, and to determine a total control quantity based on the feedforward control quantity and the feedback control quantity; and a motor drive control module configured to drive the linear motor to move according to the total control quantity.

[0007] Thirdly, this application provides a feedforward adaptive linear motor control device, comprising: one or more processors; and a memory storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the feedforward adaptive linear motor control method as described in the first aspect.

[0008] Fourthly, this application provides a storage medium containing computer-executable instructions, which, when executed by a computer processor, are used to perform the feedforward adaptive linear motor control method as described in the first aspect.

[0009] In this application, the position error is determined by comparing the actual position and reference position of the linear motor, and the acceleration error is determined by comparing the actual acceleration and reference acceleration. The position error reflects the deviation in positioning accuracy, while the acceleration error reflects the dynamic response anomalies caused by the drift of inertia and damping coefficient, providing a comprehensive and accurate disturbance characterization basis for subsequent adaptive compensation. An adaptive formula based on the Lyapunov stability criterion is introduced. The rate of change of feedforward parameters is calculated using the reference velocity, reference acceleration, and acceleration error, and then the feedforward control parameters are updated. This allows feedforward control to output control signals in advance based on the reference trajectory rather than waiting for errors to occur before adjusting, thus fundamentally avoiding the lag of single feedback control. Furthermore, the Lyapunov stability criterion ensures the stability of the feedforward parameter update process, ensuring that the feedforward parameters can compensate for the drift of inertia and damping coefficient caused by multi-physics disturbances in real time, making the compensation signal synchronized with the disturbance change and avoiding the problem of compensation phase lag. The feedforward control quantity is determined by the feedforward control parameters, and the feedback control quantity is determined by the position error. The feedforward control quantity and the feedback control quantity are merged to form the total control quantity. The feedforward control is responsible for predictable disturbance compensation, and the feedback control corrects the residual error after feedforward compensation, forming a dual guarantee of advance compensation and real-time correction. This broadens the system's disturbance suppression bandwidth. It can also feedforward cancel and then fine-tune the high-frequency dynamic multi-physics field disturbances, ensuring control accuracy and stability. Attached Figure Description

[0010] Figure 1 is a flowchart of a feedforward adaptive linear motor control method provided in an embodiment of this application; Figure 2 is a flowchart of determining the rate of change of feedforward parameters provided in an embodiment of this application; Figure 3 is a flowchart of determining feedforward control parameters provided in an embodiment of this application; Figure 4 is a schematic diagram of the closed-loop control architecture of the control system provided in an embodiment of this application; Figure 5 is a structural schematic diagram of a feedforward adaptive linear motor control device provided in an embodiment of this application; Figure 6 is a structural schematic diagram of a feedforward adaptive linear motor control equipment provided in an embodiment of this application. Detailed Implementation

[0011] To make the objectives, technical solutions, and advantages of this application clearer, specific embodiments of this application will be described in further detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely for explaining this application and not for limiting it. It should also be noted that, for ease of description, only the parts relevant to this application are shown in the drawings, not all of them. Before discussing exemplary embodiments in more detail, it should be mentioned that some exemplary embodiments are described as processes or methods depicted as flowcharts. Although the flowcharts describe operations (or steps) as sequential processes, many of these operations can be performed in parallel, concurrently, or simultaneously. Furthermore, the order of the operations can be rearranged. A process can be terminated when its operation is completed, but it may also have additional steps not included in the drawings. A process can correspond to a method, function, procedure, subroutine, subprogram, etc.

[0012] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0013] In common existing implementations, a stator dynamic coupling mechanism is introduced into the control strategy of linear motors. While maintaining the original feedback control architecture, a dual-sided damping constraint mechanism is used to achieve coordinated high-frequency micro-amplitude displacement response of the stator and mover, effectively shortening the motor's step response adjustment cycle. However, when linear motors are used to meet the precise positioning requirements of the entire motion range in actual applications, they are affected by dynamic disturbances caused by multi-physics coupling conditions (including but not limited to nonlinear attenuation of air film stiffness, enhanced stick-slip effect, temperature gradient deformation, and load mass changes). This causes significant drift in the supplementary parameters of the dual-sided damping constraint mechanism, leading to problems such as compensation phase lag and limited disturbance suppression bandwidth, thus affecting the control accuracy and stability of the linear motor.

[0014] To address the technical problems of the existing technology, the inventors discovered that the root cause is the "hysteresis" of feedback control. Feedback control requires detecting errors caused by parameter drift and disturbances before adjusting for compensation. However, the dynamic nature of parameter drift prevents the compensation signal from tracking disturbance changes in a timely manner, resulting in a phase lag in the compensation. Furthermore, the bandwidth of feedback control is limited by the system response speed, making it unable to handle high-frequency disturbances, thus limiting the disturbance suppression bandwidth and ultimately affecting control accuracy and stability. To address the "hysteresis" of feedback control, the inventors conceived of combining feedforward control with the feedback control architecture to compensate for errors caused by parameter drift and disturbances in advance. However, feedforward control involves feedforward control parameters; if these parameters are fixed, they cannot effectively compensate for errors caused by parameter drift and disturbances. In light of the technical problems existing in the prior art and the defects that exist when the feedforward control parameters are fixed, the inventors have creatively proposed a feedforward adaptive linear motor control method. This method improves the control architecture of the linear motor into a control architecture that integrates feedforward and feedback. The feedforward control parameters are updated in real time according to the actual motion parameters of the linear motor. This allows the feedforward control parameters to compensate for the drift of inertia and damping coefficients caused by dynamic disturbances. This solves the problems of compensation phase lag and disturbance suppression bandwidth limitation caused by the prior art, thereby improving the control accuracy and stability of the linear motor.

[0015] The feedforward adaptive linear motor control method provided in this embodiment can be executed by a feedforward adaptive linear motor control device. This device can be implemented through software and / or hardware. The feedforward adaptive linear motor control device can consist of two or more physical entities, or it can consist of a single physical entity. For example, the feedforward adaptive linear motor control device can be an air-bearing platform for a linear motor using high-precision control, or it can be the central controller of the air-bearing platform, with the air-bearing platform controlling the linear motor through the central controller. Alternatively, the linear motor control device can also be a control system consisting of a central controller, a linear motor, and sensors for observing the motion parameters of the linear motor.

[0016] It should be noted that the linear motor in this embodiment can be a linear motor in which the stator moves with the mover, or a linear motor in which the stator is fixed.

[0017] The feedforward adaptive linear motor control device is equipped with at least one type of operating system, including but not limited to Android, Linux, and Windows. The feedforward adaptive linear motor control device can install at least one application on the operating system; this application can be a built-in application of the operating system or an application downloaded from a third-party device or server. In this embodiment, the feedforward adaptive linear motor control device has at least one application capable of executing the feedforward adaptive linear motor control method.

[0018] For ease of understanding, this embodiment uses the control system as the main body for implementing the feedforward adaptive linear motor control method as an example.

[0019] Figure 1 shows a flowchart of a feedforward adaptive linear motor control method provided in an embodiment of this application. Referring to Figure 1, the feedforward adaptive linear motor control method specifically includes: S110, determining the position error based on the actual position of the linear motor and a preset reference position, and determining the acceleration error based on the actual acceleration of the linear motor and a preset reference acceleration.

[0020] For example, the control system controls the linear motor according to a preset control cycle. Each time the control cycle arrives, the control system executes steps S110-S140 to output a total control quantity to the linear motor. The mover of the linear motor moves linearly under the action of the total control quantity. Here, the total control quantity output by the control system can be understood as the input voltage of the linear motor.

[0021] Optionally, the control frequency corresponding to the control cycle can be set to 16KHz. In conjunction with the EtherCAT bus for communication, the feedforward control parameters can be updated in real time, thereby improving the dynamic response speed of the system.

[0022] The actual position is the position of the linear motor's mover at the arrival of the current control cycle, which can be measured by position sensors such as optical encoders. The reference position is the desired position of the linear motor's mover at the arrival of the current control cycle, which can be obtained from a preset reference trajectory of the linear motor. The reference trajectory is a pre-planned movement path of the linear motor's mover throughout the entire control process, including the time, position, velocity, and acceleration corresponding to multiple trajectory points. For example, at the arrival of the current control cycle, the control system acquires the actual position of the linear motor's mover collected by the position sensor, obtains the trajectory point corresponding to the current control cycle from the preset reference trajectory, uses the position corresponding to the trajectory point as the reference position of the linear motor's mover in the current control cycle, and subtracts the actual position from the reference position to obtain the position error.

[0023] The actual acceleration is the acceleration of the linear motor's mover at the arrival of the current control cycle. It can be directly measured by an acceleration sensor such as an inertial measurement unit, or calculated from position data collected by position sensors at multiple consecutive moments. The reference acceleration is the expected acceleration of the linear motor's mover at the arrival of the current control cycle, which can be obtained from a preset reference trajectory of the linear motor. For example, at the arrival of the current control cycle, the control system acquires the actual position X0 collected by the position sensor, as well as the position X1 collected by the position sensor in the previous acquisition cycle and the position X2 collected by the position sensor two acquisition cycles ago. Based on the position distance between the actual position X0 and position X1 and the acquisition cycle of the position sensor, the actual velocity V0 of the mover is determined. Based on the position distance between position X1 and position X2 and the acquisition cycle of the position sensor, the velocity V1 of the mover is determined. Based on the velocity difference between the actual velocity V0 and velocity V1 and the acquisition cycle of the position sensor, the actual acceleration a0 of the mover is determined. Additionally, the trajectory point corresponding to the current control cycle is obtained from the preset reference trajectory, the acceleration corresponding to the trajectory point is used as the reference acceleration of the linear motor actuator in the current control cycle, and the acceleration error is obtained by subtracting the actual acceleration from the reference acceleration.

[0024] S120. Based on the preset adaptive formula and the reference speed, reference acceleration and acceleration error of the linear motor, the rate of change of the feedforward parameter is determined. Based on the rate of change of the feedforward parameter, the feedforward control parameters are determined. The adaptive formula is derived from the error dynamics equation of the linear motor through the Lyapunov stability criterion.

[0025] For example, step S120 is the process of adaptively updating the feedforward control parameters. The control system can use a PMAC CK3M model controller to achieve adaptive updating of the feedforward control parameters.

[0026] The rate of change of feedforward parameters includes the rate of change of velocity feedforward parameters and the rate of change of acceleration feedforward parameters. The adaptive formula includes the velocity adaptive formula and the acceleration adaptive formula. The rate of change of velocity feedforward parameters can be determined by the velocity adaptive formula, thereby determining the velocity feedforward parameters. The rate of change of acceleration feedforward parameters can be determined by the acceleration adaptive formula, thereby determining the acceleration feedforward parameters. The velocity feedforward parameters are used to compensate for parameter offsets caused by viscous damping coefficients, and the acceleration feedforward parameters are used to compensate for parameter offsets caused by rotational inertia. Specifically, Figure 2 is a flowchart of determining the rate of change of feedforward parameters provided in an embodiment of this application. As shown in Figure 2, the step of determining the rate of change of feedforward parameters specifically includes S1201-S1202: S1201, determining the rate of change of velocity feedforward parameters based on a preset velocity adaptive formula and the reference velocity and acceleration error of the linear motor.

[0027] S1202. Determine the rate of change of acceleration feedforward parameters based on the preset acceleration adaptive formula, the reference acceleration of the linear motor, and the acceleration error.

[0028] For example, the speed adaptive formula is:

[0029] in, The rate of change of the velocity feedforward parameter, For acceleration error, For reference speed, For rotational inertia, For motor gain, The speed feedforward adaptive gain is used. The moment of inertia, motor gain, and speed feedforward adaptive gain can be preset. The rate of change of the speed feedforward parameters can be calculated by substituting the acceleration error and reference speed determined in the current control cycle into the above formula.

[0030] The adaptive acceleration formula is:

[0031] in, For the rate of change of the acceleration feedforward parameter, For acceleration error, The reference acceleration is used. Similarly, the moment of inertia, motor gain, and speed feedforward adaptive gain can be preset. By substituting the acceleration error and reference acceleration determined in the current control cycle into the above formula, the rate of change of the acceleration feedforward parameters can be calculated.

[0032] In this embodiment, the rate of change of the feedforward parameter is divided into two categories: velocity and acceleration, which correspond to the velocity damping drift and acceleration inertia drift of the compensation system, respectively. This makes the compensation more targeted and further reduces the compensation error.

[0033] The derivation process for the above self-used formula is as follows: First, the dynamic equation of the linear motor mover is established as follows:

[0034] in, Let be the moment of inertia of the linear motor's rotor (kg·m²). Let be the viscous damping coefficient of the linear motor mover, and K be the motor gain of the linear motor. This is the control input voltage for the linear motor. For actual acceleration, This refers to the actual speed. It can be regarded as the inertial resistance of the moving part. It can be regarded as the viscous damping resistance of the motion of the mover. This can be viewed as the driving force generated by the control input voltage u on the mover. The essence of the dynamic equation is the balance of forces, that is, the driving force must counteract the inertial drag and viscous damping drag to achieve the desired motion.

[0035] Secondly, it is clear that the control objective of the control system is to make the actual position of the mover... Reference position in the tracking reference trajectory That is, position error Converging to zero. Assuming the system parameters are precisely known, design the feedforward control quantity. This makes the feedforward control quantity Substituting the above dynamic equations, the actual position of the motor's motion is... Perfectly fits the reference position ,but The ideal feedforward equation is:

[0036] Will Substituting the calculation formula into the dynamic equation, we get:

[0037] The fact that both sides of the above formula are identical indicates that, under ideal operating conditions, the feedforward control quantity calculated based on the pre-calibrated moment of inertia, viscous damping coefficient, and motor gain can counteract the inertial resistance and viscous damping resistance generated by the system motion, thereby achieving the actual position. Reference position in the tracking reference trajectory .

[0038] However, in actual operating conditions, the moment of inertia and viscous damping coefficients will drift nonlinearly due to disturbances such as air film stiffness decay, load changes, and temperature deformation. Therefore, there is an error between the pre-calibrated moment of inertia and viscous damping coefficients and the actual ones. To address this, the moment of inertia and viscous damping coefficients can be estimated in real time, and the estimated parameters can be used to replace the actual parameters, providing an adjustable feedforward control architecture for subsequent real-time correction. Feedforward control parameters, including velocity feedforward parameters, can be designed. and acceleration feedforward parameters Velocity feedforward parameters Replace the ideal feedforward equation Acceleration feedforward parameters Replace the ideal feedforward equation Thus, the adaptive feedforward equation is constructed as follows:

[0039] Next, to measure the deviation between the estimated parameters and the true parameters, the parameter error of the velocity feedforward parameters is defined as:

[0040] The parameter error of the acceleration feedforward parameter is:

[0041] but .

[0042] in, , These are the true parameters of the ideal feedforward, and the core objective of the subsequent adaptive feedforward equation is to make... Approaching zero Approaching zero, the adaptive feedforward control effect is made close to the ideal feedforward control effect.

[0043] The control architecture of the control system is a closed-loop control architecture constructed by combining feedforward control and feedback control. Therefore, the total control quantity u = feedforward control quantity. +Feedback control quantity In this case, feedback control employs PID control; therefore, the equation for the feedback control quantity is:

[0044] in, For proportional gain, For integral gain, For differential gain, >0, >0, >0.

[0045] The formula for calculating actual acceleration can be obtained by transforming the publicly available dynamic equations:

[0046] The error dynamic equation is constructed based on the deviation between the reference acceleration and the actual acceleration:

[0047] This is for acceleration error. Substituting into the above error kinetic equation, we get:

[0048] Rearranging the above equations, we get:

[0049] in, The speed error is equal to the reference speed. Subtract actual speed The above equation further evolves into a closed-loop equation:

[0050] A four-dimensional state vector can be introduced to address the above equations:

[0051] The four-dimensional energy function constructed for the four-dimensional state vector based on the Lyapunov stability criterion is as follows:

[0052] weight matrix for:

[0053] in, For state error energy, For parameter error energy, For velocity feedforward adaptive gain, This represents the acceleration feedforward adaptive gain. The four-dimensional energy function transforms system stability into an energy decay problem. Subsequently, by proving that the reciprocal of the function is less than or equal to zero, system stability can be proven. Thus, under stable system conditions, feedforward control parameters that approximate the true parameters can be derived.

[0054] Differentiating the four-dimensional energy function V, we get:

[0055] Will Substituting into the closed-loop equation, we get:

[0056] In order to make <=0, need to eliminate those containing and The cross term must be positive; otherwise, the cross term might be positive, leading to energy dispersion. Therefore:

[0057]

[0058] Therefore, the adaptive velocity formula is derived as follows:

[0059] The adaptive acceleration formula is:

[0060] Optionally, a dynamic coupling factor can be introduced. , For proportional gain, For differential gain, As a dynamic coupling factor, For rotational inertia, the distribution of proportional, integral, and differential gains can be coordinated through dynamic coupling factors to avoid excessive single gain and ensure adaptive convergence of control parameters across the entire motion range.

[0061] exist After substituting into the closed-loop equation, a dynamic coupling factor is introduced. ,available:

[0062] Similarly, to make <=0, need to eliminate those containing and The cross term must be positive; otherwise, the cross term might be positive, leading to energy dispersion. Therefore:

[0063]

[0064] Therefore, the adaptive velocity formula is derived as follows:

[0065] The adaptive acceleration formula is:

[0066] Accordingly, the reference speed, acceleration error, position error, dynamic coupling factor, motor gain, moment of inertia, and speed feedforward adaptive gain of the linear motor can be substituted into a preset speed adaptive formula to determine the rate of change of the speed feedforward parameters. The dynamic coupling factor can be determined in advance based on the system's proportional gain, differential gain, and moment of inertia. This embodiment introduces a dynamic coupling factor into the speed adaptive formula, enabling the speed feedforward parameters to accurately match the system's dynamic coupling characteristics. This effectively compensates for speed damping drift while constraining the range of change of the speed feedforward parameters, preventing gain divergence caused by sudden changes in the air film stiffness of the air-bearing platform.

[0067] The reference acceleration, acceleration error, velocity error, dynamic coupling factor, motor gain, moment of inertia, and acceleration feedforward adaptive gain of the linear motor can be substituted into a preset acceleration adaptive formula to determine the rate of change of the acceleration feedforward parameters. Similarly, the dynamic coupling factor can be determined in advance based on the system's proportional gain, differential gain, and moment of inertia. This embodiment introduces a dynamic coupling factor into the acceleration adaptive formula, enabling the acceleration feedforward parameters to accurately match the system's dynamic coupling characteristics. This effectively compensates for acceleration inertial drift while constraining the range of change of the acceleration feedforward parameters, preventing gain divergence caused by abrupt changes in the air film stiffness of the air-bearing platform.

[0068] After determining the rate of change of the feedforward parameter, the feedforward control parameter for the current control cycle can be calculated by combining the feedforward control parameter of the previous control cycle. Specifically, Figure 3 is a flowchart of determining the feedforward control parameter provided in an embodiment of this application. As shown in Figure 3, the steps for determining the feedforward control parameter specifically include S1203-S1204: S1203, multiply the rate of change of the feedforward parameter by the preset control cycle duration to obtain the change in the feedforward parameter.

[0069] For example, the change rate of the velocity feedforward parameter is multiplied by the preset control cycle duration to obtain the change amount of the velocity feedforward parameter, and the change rate of the acceleration feedforward parameter is multiplied by the preset control cycle duration to obtain the change amount of the acceleration feedforward parameter.

[0070] S1204. Add the feedforward control parameters of the previous control cycle to the change in feedforward parameters to obtain the feedforward control parameters of the current control cycle.

[0071] For example, the velocity feedforward parameter of the previous control cycle is added to the velocity feedforward parameter change to obtain the velocity feedforward parameter of the current control cycle, and the acceleration feedforward parameter of the previous control cycle is added to the acceleration feedforward parameter change to obtain the feedforward control parameter of the current control cycle.

[0072] This embodiment determines the change in feedforward parameters by the rate of change of feedforward parameters and the duration of the control cycle, and then accumulates it with the feedforward control parameters of the previous control cycle to achieve smooth updates of feedforward control parameters, avoid system shocks caused by sudden changes in feedforward parameters, and ensure smooth motor movement.

[0073] S130. Determine the feedforward control quantity based on the feedforward control parameters, reference velocity, and reference acceleration; determine the feedback control quantity based on the position error; and determine the total control quantity based on the feedforward control quantity and the feedback control quantity.

[0074] For example, refer to the adaptive feedforward equation described above. The process for determining the feedforward control quantity is as follows: multiply the reference speed by the speed feedforward control parameter to obtain the first product; multiply the reference acceleration by the acceleration feedforward control parameter to obtain the second product; add the first product and the second product to obtain the feedforward control quantity. Wherein, For acceleration feedforward parameters, These are the acceleration feedforward control parameters. Alternatively, the calculated reference velocity, velocity feedforward control parameters, reference acceleration, and acceleration feedforward control parameters can be directly substituted into the above adaptive feedforward equation to obtain the feedforward control quantity.

[0075] Referring to the above Then, based on the position error, its differential error and integral error are determined, and the position error, differential error, and integral error are substituted into... The feedback control quantity can be calculated.

[0076] The total control quantity is obtained by adding the feedback control quantity and the feedforward control quantity.

[0077] S140: Drive the linear motor to move according to the total control quantity.

[0078] For example, a corresponding voltage is input to the linear motor according to the total control quantity, so that the linear motor moves in a straight line under the action of the corresponding voltage to track the reference trajectory. When the next control cycle arrives, the control system can execute steps S110-S140 again to cyclically control the linear motor to move according to the reference trajectory until an end command is received or a preset end condition is met.

[0079] To better illustrate the cyclic control flow of the control system in this embodiment, the closed-loop control architecture of the control system shown in Figure 4 is used as an example. As shown in Figure 4, when the current control cycle is reached, the grating ruler pushes the acquired actual position to the central controller. The central controller obtains the reference position, reference velocity, and reference acceleration through the reference trajectory, determines the actual velocity and actual acceleration based on the actual position, and performs adaptive calculation based on these motion parameters to obtain the velocity feedforward parameters. and acceleration feedforward parameters Then, the feedforward control quantity is determined through the adaptive feedforward equation. And the feedback control quantity is determined by the position error and the PID feedback equation. feedforward control quantity and feedback control quantity The total control quantity u is obtained by summing the values. The total control quantity u is then output to the linear motor. Under the action of the total control quantity u, the linear motor moves the mover in a straight line, while the grating ruler continues to collect the position of the mover.

[0080] In summary, the feedforward adaptive linear motor control method provided in this application determines the position error by comparing the actual and reference positions of the linear motor, and the acceleration error by comparing the actual and reference accelerations. The position error reflects the deviation in positioning accuracy, while the acceleration error reflects the dynamic response anomalies caused by the drift of inertia and damping coefficients, providing a comprehensive and accurate disturbance characterization basis for subsequent adaptive compensation. An adaptive formula derived based on the Lyapunov stability criterion is introduced. The rate of change of the feedforward parameters is calculated using the reference velocity, reference acceleration, and acceleration error, thereby updating the feedforward control parameters. This allows the feedforward control to output control signals in advance based on the reference trajectory, rather than waiting for errors to occur before adjustment, fundamentally avoiding the lag of single feedback control. Furthermore, the Lyapunov stability criterion ensures the stability of the feedforward parameter update process, ensuring that the feedforward parameters can compensate for the drift of inertia and damping coefficients caused by multi-physics disturbances in real time, synchronizing the compensation signal with the disturbance changes and avoiding compensation phase lag problems. The feedforward control quantity is determined by the feedforward control parameters, and the feedback control quantity is determined by the position error. The feedforward control quantity and the feedback control quantity are merged to form the total control quantity. The feedforward control is responsible for predictable disturbance compensation, and the feedback control corrects the residual error after feedforward compensation, forming a dual guarantee of advance compensation and real-time correction. This broadens the system's disturbance suppression bandwidth. It can also feedforward cancel and then fine-tune the high-frequency dynamic multi-physics field disturbances, ensuring control accuracy and stability.

[0081] Based on the above embodiments, Figure 5 is a schematic diagram of a feedforward adaptive linear motor control device provided in this application embodiment. Referring to Figure 5, the feedforward adaptive linear motor control device provided in this embodiment specifically includes: a motion parameter determination module 21, a feedforward parameter determination module 22, a control quantity determination module 23, and a motor drive control module 24.

[0082] The motion parameter determination module 21 is configured to determine the position error based on the actual position of the linear motor and a preset reference position, and to determine the acceleration error based on the actual acceleration of the linear motor and a preset reference acceleration. The feedforward parameter determination module 22 is configured to determine the feedforward parameter change rate based on a preset adaptive formula and the reference speed, reference acceleration, and acceleration error of the linear motor, and to determine the feedforward control parameters based on the feedforward parameter change rate. The adaptive formula is derived from the error dynamics equation of the linear motor using the Lyapunov stability criterion. The control quantity determination module 23 is configured to determine the feedforward control quantity based on the feedforward control parameters, reference speed, and reference acceleration, to determine the feedback control quantity based on the position error, and to determine the total control quantity based on the feedforward control quantity and the feedback control quantity. The motor drive control module 24 is configured to drive the linear motor to move according to the total control quantity.

[0083] Based on the above embodiments, the rate of change of feedforward parameters includes the rate of change of velocity feedforward parameters and the rate of change of acceleration feedforward parameters; correspondingly, the feedforward parameter determination module 22 includes: a velocity parameter rate of change determination unit, configured to determine the rate of change of velocity feedforward parameters based on a preset speed adaptive formula and the reference velocity and acceleration error of the linear motor; and an acceleration parameter rate of change determination unit, configured to determine the rate of change of acceleration feedforward parameters based on a preset acceleration adaptive formula and the reference acceleration and acceleration error of the linear motor.

[0084] Based on the above embodiments, the speed parameter change rate determination unit includes: a speed parameter change rate determination subunit, configured to substitute the linear motor's reference speed, acceleration error, position error, dynamic coupling factor, motor gain, moment of inertia, and speed feedforward adaptive gain into a preset speed adaptive formula to determine the speed feedforward parameter change rate; the speed adaptive formula is:

[0085] in, The rate of change of the velocity feedforward parameter, As a dynamic coupling factor, For positional error, For acceleration error, For reference speed, For rotational inertia, For motor gain, This is a velocity feedforward adaptive gain.

[0086] Based on the above embodiments, the acceleration parameter change rate determination unit includes: an acceleration parameter change rate determination subunit, configured to substitute the linear motor's reference acceleration, acceleration error, speed error, dynamic coupling factor, motor gain, moment of inertia, and acceleration feedforward adaptive gain into a preset acceleration adaptive formula to determine the acceleration feedforward parameter change rate; the acceleration adaptive formula is:

[0087] in, For the rate of change of the acceleration feedforward parameter, As a dynamic coupling factor, For speed error, For acceleration error, For reference acceleration, For rotational inertia, For motor gain, For acceleration feedforward adaptive gain, the speed error is determined based on the actual speed of the linear motor and the preset reference speed.

[0088] Based on the above embodiments, the formula for calculating the dynamic coupling factor is as follows:

[0089] in, For proportional gain, For differential gain, As a dynamic coupling factor, Let be the moment of inertia.

[0090] Based on the above embodiments, the feedforward parameter determination module 22 includes: a parameter change determination unit, configured to multiply the feedforward parameter change rate by a preset control cycle duration to obtain the feedforward parameter change amount; and a feedforward parameter determination unit, configured to add the feedforward control parameter of the previous control cycle to the feedforward parameter change amount to obtain the feedforward control parameter of the current control cycle.

[0091] Based on the above embodiments, the feedforward control parameters include velocity feedforward control parameters and acceleration feedforward control parameters; correspondingly, the control quantity determination module includes: a first product unit configured to multiply the reference velocity by the velocity feedforward control parameters to obtain a first product; a second product unit configured to determine the reference acceleration by multiplying the acceleration feedforward control parameters to obtain a second product; and a feedforward control quantity determination unit configured to add the first product and the second product to obtain the feedforward control quantity.

[0092] The feedforward adaptive linear motor control device provided in this application determines the position error by comparing the actual position and reference position of the linear motor, and determines the acceleration error by comparing the actual acceleration and reference acceleration. The position error reflects the deviation in positioning accuracy, while the acceleration error reflects the dynamic response anomalies caused by the drift of inertia and damping coefficient, providing a comprehensive and accurate disturbance characterization basis for subsequent adaptive compensation. An adaptive formula derived based on the Lyapunov stability criterion is introduced. The rate of change of the feedforward parameters is calculated using the reference velocity, reference acceleration, and acceleration error, thereby updating the feedforward control parameters. This allows the feedforward control to output control signals in advance based on the reference trajectory, rather than waiting for errors to occur before adjustment, fundamentally avoiding the lag of single feedback control. Furthermore, the Lyapunov stability criterion ensures the stability of the feedforward parameter update process, ensuring that the feedforward parameters can compensate for the drift of inertia and damping coefficient caused by multi-physics disturbances in real time, synchronizing the compensation signal with the disturbance change and avoiding compensation phase lag problems. The feedforward control quantity is determined by the feedforward control parameters, and the feedback control quantity is determined by the position error. The feedforward control quantity and the feedback control quantity are merged to form the total control quantity. The feedforward control is responsible for predictable disturbance compensation, and the feedback control corrects the residual error after feedforward compensation, forming a dual guarantee of advance compensation and real-time correction. This broadens the system's disturbance suppression bandwidth. It can also feedforward cancel and then fine-tune the high-frequency dynamic multi-physics field disturbances, ensuring control accuracy and stability.

[0093] The feedforward adaptive linear motor control device provided in this application embodiment can be used to execute the feedforward adaptive linear motor control method provided in the above embodiment, and has corresponding functions and beneficial effects.

[0094] Figure 6 is a schematic diagram of a feedforward adaptive linear motor control device according to an embodiment of this application. Referring to Figure 6, the feedforward adaptive linear motor control device includes: a processor 31, a memory 32, a communication device 33, an input device 34, and an output device 35. The number of processors 31 and the number of memories 32 in the feedforward adaptive linear motor control device can be one or more. The processor 31, memory 32, communication device 33, input device 34, and output device 35 of the feedforward adaptive linear motor control device can be connected via a bus or other means.

[0095] The memory 32, as a computer-readable storage medium, can be used to store software programs, computer-executable programs, and modules, such as program instructions / modules corresponding to the feedforward adaptive linear motor control method in any embodiment of this application (e.g., motion parameter determination module 21, feedforward parameter determination module 22, control quantity determination module 23, and motor drive control module 24 in the feedforward adaptive linear motor control device). The memory 32 may primarily include a program storage area and a data storage area. The program storage area may store the operating system and at least one application program required for a function; the data storage area may store data created based on the use of the device, etc. Furthermore, the memory 32 may include high-speed random access memory and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device. In some instances, the memory may further include memory remotely located relative to the processor, and these remote memories can be connected to the device via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0096] The communication device 33 is used for data transmission.

[0097] The processor 31 executes various functional applications and data processing of the device by running software programs, instructions and modules stored in the memory 32, thereby realizing the above-mentioned feedforward adaptive linear motor control method.

[0098] Input device 34 can be used to receive input digital or character information, and to generate key signal inputs related to user settings and function control of the device. Output device 35 may include display devices such as a display screen.

[0099] The feedforward adaptive linear motor control device provided above can be used to execute the feedforward adaptive linear motor control method provided in the above embodiments, and has corresponding functions and beneficial effects.

[0100] This application embodiment also provides a storage medium containing computer-executable instructions. When executed by a computer processor, the computer-executable instructions are used to execute a feedforward adaptive linear motor control method. This feedforward adaptive linear motor control method includes: determining a position error based on the actual position of the linear motor and a preset reference position; determining an acceleration error based on the actual acceleration of the linear motor and a preset reference acceleration; determining a feedforward parameter change rate based on a preset adaptive formula and the reference speed, reference acceleration, and acceleration error of the linear motor; determining feedforward control parameters based on the feedforward parameter change rate; the adaptive formula is derived from the error dynamics equation of the linear motor using the Lyapunov stability criterion; determining a feedforward control quantity based on the feedforward control parameters, reference speed, and reference acceleration; determining a feedback control quantity based on the position error; determining a total control quantity based on the feedforward control quantity and the feedback control quantity; and driving the linear motor to move according to the total control quantity.

[0101] Storage medium – any type of memory device or storage device. The term “storage medium” is intended to include: mounting media, such as CD-ROM, floppy disk, or magnetic tape devices; computer system memory or random access memory, such as DRAM, DDR RAM, SRAM, EDO RAM, Rambus RAM, etc.; non-volatile memory, such as flash memory, magnetic media (e.g., hard disk or optical storage); registers or other similar types of memory elements, etc. Storage medium may also include other types of memory or combinations thereof. Furthermore, storage medium may reside in a first computer system in which the program is executed, or it may reside in a different second computer system connected to the first computer system via a network (such as the Internet). The second computer system can provide program instructions to the first computer for execution. The term “storage medium” can include two or more storage media residing in different locations (e.g., in different computer systems connected via a network). Storage medium may store program instructions (e.g., specifically implemented as a computer program) executable by one or more processors.

[0102] Of course, the computer-executable instructions provided in the embodiments of this application are not limited to the feedforward adaptive linear motor control method described above, but can also execute related operations in the feedforward adaptive linear motor control method provided in any embodiment of this application.

[0103] The feedforward adaptive linear motor control device, storage medium, and feedforward adaptive linear motor control equipment provided in the above embodiments can execute the feedforward adaptive linear motor control method provided in any embodiment of this application. For technical details not described in detail in the above embodiments, please refer to the feedforward adaptive linear motor control method provided in any embodiment of this application.

[0104] The above description is merely a preferred embodiment and the technical principles employed in this application. This application is not limited to the specific embodiments described herein, and various obvious changes, readjustments, and substitutions that can be made by those skilled in the art will not depart from the scope of protection of this application. Therefore, although this application has been described in detail through the above embodiments, this application is not limited to the above embodiments, and may include many other equivalent embodiments without departing from the concept of this application. The scope of this application is determined by the scope of the claims.

Claims

1. A linear motor control method based on feedforward adaptive control, characterized in that, include: The position error is determined based on the actual position of the linear motor and the preset reference position, and the acceleration error is determined based on the actual acceleration of the linear motor and the preset reference acceleration. The feedforward parameter change rate is determined based on the preset adaptive formula and the reference speed, reference acceleration and acceleration error of the linear motor. The feedforward control parameters are determined based on the feedforward parameter change rate. The adaptive formula is derived from the error dynamics equation of the linear motor through the Lyapunov stability criterion. The feedforward control quantity is determined based on the feedforward control parameters, the reference speed, and the reference acceleration; the feedback control quantity is determined based on the position error; the total control quantity is determined based on the feedforward control quantity and the feedback control quantity; and the linear motor is driven to move according to the total control quantity.

2. The linear motor control method based on feedforward adaptive control according to claim 1, characterized in that, The rate of change of the feedforward parameters includes the rate of change of the velocity feedforward parameter and the rate of change of the acceleration feedforward parameter; correspondingly, the determination of the rate of change of the feedforward parameters based on the preset adaptive formula and the reference velocity, reference acceleration, and acceleration error of the linear motor includes: determining the rate of change of the velocity feedforward parameter based on the preset speed adaptive formula and the reference velocity and acceleration error of the linear motor; and determining the rate of change of the acceleration feedforward parameter based on the preset acceleration adaptive formula and the reference acceleration and acceleration error of the linear motor.

3. The linear motor control method based on feedforward adaptive control according to claim 2, characterized in that, The determination of the rate of change of the speed feedforward parameters based on the preset speed adaptive formula and the reference speed and acceleration error of the linear motor includes: substituting the reference speed, acceleration error, position error, dynamic coupling factor, motor gain, moment of inertia, and speed feedforward adaptive gain of the linear motor into the preset speed adaptive formula to determine the rate of change of the speed feedforward parameters; the speed adaptive formula is: in, The rate of change of the velocity feedforward parameter, As a dynamic coupling factor, For positional error, For acceleration error, For reference speed, For rotational inertia, For motor gain, This is a velocity feedforward adaptive gain.

4. The linear motor control method based on feedforward adaptive control according to claim 2, characterized in that, The determination of the rate of change of the acceleration feedforward parameter based on the preset acceleration adaptive formula and the reference acceleration and acceleration error of the linear motor includes: substituting the reference acceleration, acceleration error, velocity error, dynamic coupling factor, motor gain, moment of inertia, and acceleration feedforward adaptive gain of the linear motor into the preset acceleration adaptive formula to determine the rate of change of the acceleration feedforward parameter; the acceleration adaptive formula is: in, For the rate of change of the acceleration feedforward parameter, As a dynamic coupling factor, For speed error, For acceleration error, For reference acceleration, For rotational inertia, For motor gain, As an acceleration feedforward adaptive gain, the speed error is determined based on the actual speed of the linear motor and a preset reference speed.

5. The linear motor control method based on feedforward adaptation according to claim 2 or 3, characterized in that, The formula for calculating the dynamic coupling factor is as follows: in, For proportional gain, For differential gain, As a dynamic coupling factor, Let be the moment of inertia.

6. The linear motor control method based on feedforward adaptive control according to claim 1, characterized in that, The step of determining the feedforward control parameter based on the feedforward parameter change rate includes: multiplying the feedforward parameter change rate by a preset control cycle duration to obtain the feedforward parameter change amount; and adding the feedforward control parameter of the previous control cycle to the feedforward parameter change amount to obtain the feedforward control parameter of the current control cycle.

7. The linear motor control method based on feedforward adaptive control according to claim 2, characterized in that, The feedforward control parameters include velocity feedforward control parameters and acceleration feedforward control parameters; correspondingly, determining the feedforward control quantity based on the feedforward control parameters, the reference velocity, and the reference acceleration includes: multiplying the reference velocity by the velocity feedforward control parameters to obtain a first product; determining the reference acceleration by multiplying by the acceleration feedforward control parameters to obtain a second product; and adding the first product and the second product to obtain the feedforward control quantity.

8. A linear motor control device based on feedforward adaptive control, characterized in that, include: The motion parameter determination module is configured to determine the position error based on the actual position of the linear motor and a preset reference position, and to determine the acceleration error based on the actual acceleration of the linear motor and a preset reference acceleration. The feedforward parameter determination module is configured to determine the rate of change of the feedforward parameters based on a preset adaptive formula and the reference speed, reference acceleration, and acceleration error of the linear motor, and to determine the feedforward control parameters based on the rate of change of the feedforward parameters. The adaptive formula is derived from the error dynamics equation of the linear motor using the Lyapunov stability criterion. The control quantity determination module is configured to determine a feedforward control quantity based on the feedforward control parameters, the reference velocity, and the reference acceleration; determine a feedback control quantity based on the position error; and determine a total control quantity based on the feedforward control quantity and the feedback control quantity. The motor drive control module is configured to drive the linear motor to move according to the total control quantity.

9. A linear motor control device based on feedforward adaptive control, characterized in that, include: One or more processors; A memory that stores one or more programs, which, when executed by one or more processors, enable the one or more processors to implement the feedforward adaptive linear motor control method as described in any one of claims 1-7.

10. A storage medium containing computer-executable instructions, characterized in that, The computer-executable instructions, when executed by a computer processor, are used to perform the feedforward adaptive linear motor control method as described in any one of claims 1-7.

Images