Piezoelectric system hysteresis modeling and compound control method and device and electronic equipment

Abstract

The invention provides a piezoelectric system hysteresis modeling and compound control method and device and electronic equipment, and relates to the technical field of motion control. The method comprises the following steps: constructing a compensation model for performing feed-forward compensation on the piezoelectric system; wherein the compensation model is an inverse model of the control model related to the asymmetric rate; determining a self-adaptive control algorithm for performing feedback compensation on the piezoelectric system; and determining an input control quantity of the piezoelectric system according to a feedforward control quantity determined by feedforward compensation performed by the compensation model and a feedback control quantity determined by feedback compensation performed based on an adaptive control algorithm. According to the device, a feedforward controller is connected with the input end of a piezoelectric system, and a feedback controller is connected with the input end and the output end of the piezoelectric system; the feed-forward controller is used for performing feed-forward compensation to determine a feed-forward control quantity; the feedback controller is used for performing feedback compensation to determine a feedback control quantity; and the control system is used for determining the input control quantity of the piezoelectric system according to the feedforward control quantity and the feedback control quantity.

Description

Technical Field

[0001] The present application relates to the field of motion control technology, and in particular to a piezoelectric system hysteresis modeling and composite control method, device and electronic equipment. Background Art

[0002] Piezoelectric ceramic actuators, due to their advantages such as high displacement resolution, fast response speed, and high-precision control capabilities, are widely used in high-precision positioning applications such as micro-nano positioning, biomedicine, aerospace, and optical precision engineering. However, the inherent hysteresis and nonlinear characteristics of piezoelectric ceramic materials significantly affect the control accuracy and stability of the system. Hysteresis manifests as a nonlinear relationship between the input signal and the output displacement, leading to uncertainty in the system output, which in turn affects the stability, dynamic response, and positioning accuracy of the piezoelectric system.

[0003] At present, in order to reduce the uncertainty caused by hysteresis characteristics, strategic control is usually used to compensate for the input. For example, the input of the piezoelectric ceramic actuator can be compensated using the PI (Prandtl-Ishlinskii) model. However, this compensation method can only compensate for symmetrical changes, while in actual application scenarios, there are usually asymmetric changes, resulting in the low universality of existing compensation control methods. It is impossible to accurately characterize the hysteresis characteristics of the piezoelectric ceramic actuator and compensate for it under different circumstances. The compensation accuracy and efficiency are low, and it cannot meet the high-precision and high-efficiency input control requirements of the piezoelectric ceramic actuator, thereby failing to achieve stable and efficient control of the piezoelectric system. Summary of the Invention

[0004] In view of this, the purpose of the embodiments of the present application is to provide a piezoelectric system hysteresis modeling and composite control method, device and electronic equipment to improve the hysteresis characteristics of the piezoelectric system in the prior art and improve the control accuracy of the piezoelectric system.

[0005] In order to solve the above problems, in a first aspect, an embodiment of the present application provides a piezoelectric system hysteresis modeling and composite control method, the method comprising: Constructing a compensation model for feedforward compensation of the piezoelectric system; wherein the compensation model is an inverse model of the asymmetry rate-related control model; determining an adaptive control algorithm for feedback compensation of the piezoelectric system; The input control amount of the piezoelectric system is determined by performing feedforward compensation based on the compensation model and the feedback control amount based on the adaptive control algorithm.

[0006] In the above implementation process, a compensation model for feedforward compensation of the piezoelectric system can be constructed, and the hysteresis characteristics of the piezoelectric system can be accurately characterized based on the inverse model of the asymmetry rate-related control model to achieve high-precision feedforward compensation, and an adaptive control algorithm for feedback compensation of the piezoelectric system can be determined. From the perspectives of feedforward and feedback, the input of the piezoelectric system can be compensated respectively to obtain the corresponding feedforward control quantity and feedback control quantity, and the final input control quantity of the piezoelectric system can be obtained by combining the feedforward control quantity and the feedback control quantity. It is possible to improve the characterization and compensation of the hysteresis characteristics of the piezoelectric system based on the compensation model, and at the same time form a composite control of the input in combination with the adaptive control algorithm, further improve the anti-interference ability and control accuracy of the piezoelectric system, achieve accurate tracking of the desired trajectory, meet the high-precision and high-efficiency input control requirements of the piezoelectric system, and achieve stable and efficient control effects of the piezoelectric system.

[0007] Optionally, constructing a compensation model for performing feedforward compensation on the piezoelectric system includes: Constructing the asymmetric rate-dependent control model based on the initial model; wherein the initial model includes a PI model, and the control model includes a rate-dependent asymmetric generalized PI model; determining target parameters of the control model based on historical data of the piezoelectric system; The control model using the target parameters is inversely processed to obtain the compensation model for feed-forward compensation of the piezoelectric system.

[0008] In the above implementation process, when constructing the compensation model, the PI model can be selected as the initial model. Considering that the hysteresis phenomenon of the piezoelectric ceramic actuator in the actual piezoelectric system is asymmetric and input change rate-dependent, a generalized PI model related to the asymmetry rate can be constructed based on the initial model as the control model. In order to introduce the dead zone model and the dynamic threshold concept on the basis of the traditional PI model, the control model can accurately characterize the actual hysteresis characteristics of the piezoelectric system. In order to make the constructed control model more compatible with the actual piezoelectric system, the relevant parameters in the control model can be identified based on the historical data of the piezoelectric system, and the target parameters of the control model can be determined to minimize the error between the output of the control model and the experimental data, further improving the accuracy of characterizing the hysteresis characteristics. In addition, the control model using the target parameters can be inversely processed to obtain the corresponding inverse model as the compensation model to achieve feedforward compensation of the hysteresis characteristics of the piezoelectric system. By constructing the inverse model of the asymmetry rate-dependent control model, the hysteresis characteristics of the piezoelectric system can be characterized and compensated, effectively improving the accuracy and efficiency of compensating for the hysteresis characteristics.

[0009] Optionally, constructing the control model related to the asymmetric rate based on the initial model includes: Determining a corresponding dead zone model based on the dead zone operator of the initial model; determining a dynamic threshold value characterizing a hysteresis characteristic of the piezoelectric system based on the rate of change; The initial model is adjusted according to the dead zone model and the dynamic threshold to obtain the control model related to the asymmetry rate.

[0010] In the above implementation process, when constructing the asymmetry rate-related control model, considering that the traditional PI model cannot describe the asymmetric relationship of the actual hysteresis characteristics in the piezoelectric system, the corresponding dead zone model can be determined based on the dead zone operator of the initial model. Moreover, considering the impact of the input change rate on the hysteresis characteristics, the dynamic threshold that characterizes the hysteresis characteristics of the piezoelectric system can be determined. The initial model can be adjusted and improved by combining the dead zone model and the dynamic threshold to obtain the asymmetry rate-related control model. The ability to improve the initial model by combining the dead zone model and the dynamic threshold effectively improves the accuracy of the control model in characterizing the hysteresis characteristics.

[0011] Optionally, adjusting the initial model according to the dead zone model and the dynamic threshold to obtain the control model related to the asymmetry rate includes: The initial model is replaced based on the dead zone model to obtain an optimized hysteresis operator; Constructing a process model according to the optimized hysteresis operator and the initial model; wherein the process model includes a GPI model; The process model is adjusted according to the dynamic threshold to obtain the control model, which includes: ; in, represents the output of the control model, represents the input of the control model, represents the output of the dead zone model, and is the weight parameter, n is the total number of operators, represents the dynamic threshold of the i-th operator.

[0012] In the above implementation process, when adjusting the initial model in combination with the deadband model and the dynamic threshold, the initial model can be replaced based on the deadband model to obtain an improved optimized hysteresis operator. Then, the corresponding process model can be constructed based on the optimized hysteresis operator and the initial model. Considering that process models generally use fixed thresholds and ignore the impact of the input change rate on hysteresis, the process model can be adjusted based on the dynamic threshold to obtain the corresponding control model. The ability to gradually improve the initial model based on the deadband model and the dynamic threshold effectively improves the effectiveness and accuracy of the control model.

[0013] Optionally, the historical data includes associated input data and output data; The determining the target parameters of the control model based on the historical data of the piezoelectric system includes: Substituting multiple sets of the input data and the corresponding output data into the control model for calculation, thereby obtaining an initial parameter range of the model parameters in the control model; wherein the model parameters include a first weight parameter and a dynamic threshold coefficient of the control model; Determining physical constraints of the model parameters based on operating parameters of the piezoelectric system; The target parameter is determined by combining the physical constraint condition and the initial parameter range.

[0014] In the above implementation process, the historical data may include input data and output data that are correlated with the historical conditions of the piezoelectric system. When determining the target parameters in the control model, multiple sets of input data and output data may be substituted into the control model for calculation to obtain the initial parameter ranges of various different types of model parameters in the control model. On this basis, considering the physical meanings of the various model parameters, the physical constraints of the model parameters may be determined according to the working parameters of the piezoelectric system, and screening may be performed in combination with the physical constraints and the initial parameter ranges. Within the initial parameter range, the parameters that meet the physical constraints are determined as the target parameters. The control model can be parameter-identified according to the actual conditions of the piezoelectric system, effectively improving the accuracy of the target parameters and the adaptability of the target parameters to the piezoelectric system, thereby improving the effectiveness of the control model.

[0015] Optionally, performing inverse processing on the control model using the target parameters to obtain the compensation model for performing feedforward compensation on the piezoelectric system includes: Performing an inverse solution on the control model using the target parameter to obtain inverse model parameters of the compensation model; wherein the inverse model parameters include a second weight parameter and a threshold parameter; Based on the inverse model parameters, the compensation model for performing feed-forward compensation on the piezoelectric system is constructed.

[0016] In the above implementation process, during the construction of the inverse model, the control model using the target parameters can be inversely solved to obtain various types of inverse model parameters corresponding to the inverse model. Then, a corresponding compensation model can be constructed based on the inverse model parameters to perform feedforward compensation for the hysteresis characteristics of the piezoelectric system. The inverse model of the control model can be constructed as a compensation model through analytical inverse processing, and the hysteresis characteristics of the piezoelectric system can be feedforward compensated based on the compensation model, thereby improving the accuracy and efficiency of the feedforward compensation.

[0017] Optionally, determining an adaptive control algorithm for performing feedback compensation on the piezoelectric system includes: determining an error variable of the piezoelectric system according to a dynamic equation and a state-space expression of the piezoelectric system; determining an adaptation rate of the piezoelectric system based on a control gain of the piezoelectric system and the error variable; The adaptive control algorithm for performing feedback compensation on the piezoelectric system is determined according to the adaptive rate.

[0018] In the above implementation process, in order to improve the anti-interference capability of the piezoelectric system, an adaptive control algorithm for feedback compensation of the piezoelectric system can be determined. The error variable of the piezoelectric system can be determined based on the dynamic equation and state-space expression of the piezoelectric system. Then, the adaptive rate of the piezoelectric system can be determined based on the gain system and the error variable. Based on the adaptive rate, the adaptive control algorithm is determined to perform feedback compensation on the input of the piezoelectric system. The ability to determine the corresponding adaptive control algorithm for feedback compensation based on the stability requirements of the piezoelectric system further reduces the impact of hysteresis characteristics on the piezoelectric system and improves the control accuracy of the piezoelectric system.

[0019] In a second aspect, an embodiment of the present application provides a piezoelectric system hysteresis modeling and composite control device, the device comprising: a control system and a piezoelectric system; The control system includes a feedforward controller and a feedback controller, the feedforward controller is provided with a compensation model for performing feedforward compensation on the piezoelectric system, and the feedback controller is provided with an adaptive control algorithm for performing feedback compensation on the piezoelectric system; The feedforward controller is connected to the input end of the piezoelectric system, and the feedback controller is connected to the input end and the output end of the piezoelectric system; The feedforward controller is used to perform feedforward compensation and determine the feedforward control amount; The feedback controller is used to perform feedback compensation to determine the feedback control amount; The control system is used to determine the input control quantity of the piezoelectric system based on the feedforward control quantity and the feedback control quantity.

[0020] In the above implementation process, the piezoelectric system hysteresis modeling and composite control device may include a control system for the piezoelectric system and for compensating the input of the piezoelectric system. The control system may include a feedforward controller and a feedback controller. The two controllers are respectively connected to different ports of the piezoelectric system, and corresponding models or algorithms are set in each controller to implement corresponding compensation functions. The feedforward controller can accurately characterize the hysteresis characteristics of the piezoelectric system based on the inverse model of the asymmetry rate-related control model, achieving high-precision feedforward compensation. The feedback controller can achieve feedback compensation from a composite control perspective. It can compensate the input of the piezoelectric system from both the feedforward and feedback perspectives, obtain corresponding feedforward control quantities and feedback control quantities, and combine the feedforward control quantities and feedback control quantities to obtain the final input control quantity of the piezoelectric system. It can improve the characterization and compensation of the hysteresis characteristics of the piezoelectric system based on the compensation model, and at the same time form a composite control of the input in combination with an adaptive control algorithm, further improving the anti-interference ability and control accuracy of the piezoelectric system, achieving accurate tracking of the desired trajectory, meeting the high-precision and high-efficiency input control requirements of the piezoelectric system, and achieving stable and efficient control effects of the piezoelectric system.

[0021] In a third aspect, an embodiment of the present application further provides an electronic device comprising a memory and a processor, wherein the memory stores program instructions, and when the processor reads and runs the program instructions, it executes the steps in any implementation method of the above-mentioned piezoelectric system hysteresis modeling and composite control method.

[0022] In a fourth aspect, an embodiment of the present application further provides a computer program product, which includes a computer program / instruction, and when the computer program / instruction is executed by a processor, implements the steps of any one of the above-mentioned piezoelectric system hysteresis modeling and composite control methods.

[0023] In summary, the embodiments of the present application provide a piezoelectric system hysteresis modeling and composite control method, device and electronic device, which can improve the characterization and compensation of the hysteresis characteristics of the piezoelectric system based on the compensation model, and at the same time combine the adaptive control algorithm to form a composite control of the input, further improve the piezoelectric system's anti-interference ability and control accuracy, achieve accurate tracking of the desired trajectory, meet the high-precision and high-efficiency input control requirements of the piezoelectric system, and achieve stable and efficient control effects of the piezoelectric system. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments of the present application. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 A block diagram of an electronic device provided in an embodiment of the present application; Figure 2 A flow chart of a piezoelectric system hysteresis modeling and composite control method provided in an embodiment of the present application; Figure 3 A detailed flowchart of step S200 provided in an embodiment of the present application; Figure 4 A detailed flowchart of step S210 provided in an embodiment of the present application; Figure 5 A detailed flowchart of step S213 provided in an embodiment of the present application; Figure 6 A detailed flowchart of step S220 provided in an embodiment of the present application; Figure 7 A detailed flowchart of step S230 provided in an embodiment of the present application; Figure 8 A detailed flowchart of step S300 provided in an embodiment of the present application; Figure 9 A schematic structural diagram of a piezoelectric system hysteresis modeling and composite control device provided in an embodiment of the present application.

[0026] Icons: 100-electronic device; 111-memory; 112-memory controller; 113-processor; 114-peripheral interface; 115-input and output unit; 116-display unit; 500-piezoelectric system hysteresis modeling and composite control device; 510-control system; 520-piezoelectric system; 511-feedforward controller; 512-feedback controller. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the embodiments described are only part of the embodiments of the present application, not all of them. Based on the embodiments of the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the embodiments of the present application.

[0028] In existing solutions, in order to reduce the uncertainty caused by hysteresis characteristics, strategic control is usually used to compensate for the input. For example, considering that the PI model can be used to describe the hysteresis nonlinear behavior in materials or systems, the input of the piezoelectric ceramic actuator can be compensated based on the PI model. However, this compensation method can only compensate for symmetrical changes, while the hysteresis phenomenon of the piezoelectric ceramic actuator in actual applications often presents asymmetry, resulting in the low universality of the existing compensation control method. It is impossible to accurately characterize the hysteresis characteristics of the piezoelectric ceramic actuator and compensate for it under different circumstances. The compensation accuracy and efficiency are low, and it cannot meet the high-precision and high-efficiency input control requirements of the piezoelectric ceramic actuator, thereby failing to achieve stable and efficient control of the piezoelectric system.

[0029] In order to solve the above problems, an embodiment of the present application provides a piezoelectric system hysteresis modeling and composite control method, which is applied to electronic devices. The electronic devices can be various types of electronic devices with logical calculation functions, such as control systems that can be set in piezoelectric system hysteresis modeling and composite control devices. It can improve the characterization and compensation of the hysteresis characteristics of the piezoelectric system based on the compensation model, and at the same time combine the adaptive control algorithm to form a composite control of the input, further improve the anti-interference ability and control accuracy of the piezoelectric system, achieve accurate tracking of the desired trajectory, meet the high-precision and high-efficiency input control requirements of the piezoelectric system, and achieve stable and efficient control effects of the piezoelectric system.

[0030] Optionally, see Figure 1 , Figure 1 This is a block diagram of an electronic device provided in an embodiment of the present application. The electronic device 100 may include a memory 111, a storage controller 112, a processor 113, a peripheral interface 114, an input and output unit 115, and a display unit 116. It will be understood by those skilled in the art that Figure 1 The structure shown is only for illustration and does not limit the structure of the electronic device 100. For example, the electronic device 100 may further include Figure 1 More or fewer components than shown, or with Figure 1 Different configurations shown.

[0031] The aforementioned memory 111, storage controller 112, processor 113, peripheral interface 114, input / output unit 115, and display unit 116 are electrically connected to each other, directly or indirectly, to enable data transmission or interaction. For example, these components may be electrically connected to each other via one or more communication buses or signal lines. The aforementioned processor 113 is used to execute the executable modules stored in the memory.

[0032] The memory 111 may be, but is not limited to, a random access memory (RAM), a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), etc. The memory 111 is used to store programs, and the processor 113 executes the programs after receiving an execution instruction. The method executed by the electronic device 100 defined by the process disclosed in any embodiment of the present application may be applied to the processor 113 or implemented by the processor 113.

[0033] The processor 113 may be an integrated circuit chip with signal processing capabilities. The processor 113 may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. The methods, steps, and logic block diagrams disclosed in the embodiments of the present application may be implemented or executed. The general-purpose processor may be a microprocessor or any conventional processor.

[0034] The peripheral interface 114 couples various input / output devices to the processor 113 and the memory 111. In some embodiments, the peripheral interface 114, the processor 113, and the memory controller 112 can be implemented in a single chip. In other embodiments, they can be implemented in separate chips.

[0035] The input / output unit 115 is used to provide input data to the user. The input / output unit 115 can be, but is not limited to, a mouse and a keyboard.

[0036] The display unit 116 provides an interactive interface (e.g., a user operation interface) between the electronic device 100 and the user or is used to display image data for the user's reference. In this embodiment, the display unit can be a liquid crystal display or a touch display. If it is a touch display, it can be a capacitive touch screen or a resistive touch screen that supports single-point and multi-point touch operations. Supporting single-point and multi-point touch operations means that the touch display can sense touch operations generated simultaneously from one or more locations on the touch display, and pass the sensed touch operations to the processor for calculation and processing. In this embodiment of the present application, the display unit 116 can display various information such as the working status of the piezoelectric system.

[0037] The electronic device in this embodiment can be used to execute each step of the piezoelectric system hysteresis modeling and composite control method provided in the embodiments of this application. The following describes in detail the implementation process of the piezoelectric system hysteresis modeling and composite control method through several embodiments.

[0038] See also Figure 2 , Figure 2 A flow chart of a piezoelectric system hysteresis modeling and composite control method provided in an embodiment of the present application, the method may include steps S200-S400.

[0039] Step S200: constructing a compensation model for performing feed-forward compensation on the piezoelectric system.

[0040] Among them, the compensation model is the inverse model of the asymmetry rate-related control model, such as the inverse model of the asymmetry rate-related generalized PI model, etc., which can accurately characterize the hysteresis characteristics of the piezoelectric system based on the inverse model of the asymmetry rate-related control model to achieve high-precision feedforward compensation.

[0041] Step S300: determining an adaptive control algorithm for feedback compensation of a piezoelectric system.

[0042] Among them, an adaptive control algorithm for feedback compensation of the piezoelectric system can be determined according to the actual use of the piezoelectric system. The adaptive control algorithm can be an algorithm set in an adaptive controller designed based on Lyapunov stability theory and capable of proving the closed-loop stability of the piezoelectric system.

[0043] Step S400 , determining the input control variable of the piezoelectric system based on the feedforward control variable determined by performing feedforward compensation on the compensation model and the feedback control variable determined by performing feedback compensation on the basis of the adaptive control algorithm.

[0044] Among them, the input of the piezoelectric system can be compensated from the two perspectives of feedforward and feedback, respectively, to obtain the corresponding feedforward control quantity and feedback control quantity, and the final input control quantity of the piezoelectric system can be obtained by combining the feedforward control quantity and the feedback control quantity.

[0045] Optionally, the feedforward control variable and the feedback control variable may be added to obtain the final input control variable of the piezoelectric system.

[0046] Optionally, the piezoelectric system may be provided with various devices such as piezoelectric ceramic actuators.

[0047] exist Figure 2 In the embodiment shown, the hysteresis characteristics of the piezoelectric system can be improved by characterizing and compensating for them based on the compensation model, and at the same time, a composite control of the input can be formed by combining the adaptive control algorithm, thereby further improving the anti-interference ability and control accuracy of the piezoelectric system, achieving accurate tracking of the desired trajectory, meeting the high-precision and high-efficiency input control requirements of the piezoelectric system, and achieving stable and efficient control effects of the piezoelectric system.

[0048] Optionally, see Figure 3 , Figure 3 A detailed flowchart of step S200 is provided in an embodiment of the present application. Step S200 may include steps S210-S230.

[0049] Step S210: constructing an asymmetric rate-related control model based on the initial model.

[0050] The initial model may include a PI model, and the control model may include a rate-dependent asymmetric generalized PI model, namely, an RD-GPI model. When constructing the compensation model, the PI model may be selected as the initial model. Considering that the hysteresis phenomenon of the piezoelectric ceramic actuator in the actual piezoelectric system is asymmetric and input change rate-dependent, a rate-dependent asymmetric generalized PI model may be constructed as the control model based on the initial model. This introduces a dead zone model and a dynamic threshold concept on the basis of the traditional PI model, enabling the control model to accurately characterize the actual hysteresis characteristics of the piezoelectric system.

[0051] Optionally, before constructing the RD-GPI model, the initial model is first clarified, that is, the expression of the PI model is: ; in, represents the output of the initial model, represents the input of the initial model, and is a weight parameter used to adjust the contribution of each hysteresis operator to the output. represents the hysteresis operator, n is the total number of operators, Represents the threshold of the hysteresis operator, the hysteresis operator The specific definition is: .

[0052] Step S220 : determining target parameters of the control model based on historical data of the piezoelectric system.

[0053] Among them, in order to make the constructed control model more compatible with the actual piezoelectric system, the relevant parameters in the control model can be identified based on the historical data of the piezoelectric system, and the target parameters of the control model can be determined to minimize the error between the output of the control model and the experimental data, further improving the accuracy of characterizing the hysteresis characteristics.

[0054] Optionally, the historical data of the piezoelectric system may be multiple sets of input data and output data under historical working conditions of the piezoelectric system.

[0055] Step S230 , performing inverse processing on the control model using the target parameters to obtain a compensation model for performing feedforward compensation on the piezoelectric system.

[0056] Among them, considering that the control model can only characterize the hysteresis characteristics of the piezoelectric system, the control model using the target parameters can be inversely processed to obtain the corresponding inverse model as a compensation model to achieve feedforward compensation for the hysteresis characteristics of the piezoelectric system.

[0057] exist Figure 3 In the embodiment described, the hysteresis characteristics of the piezoelectric system can be characterized and compensated by constructing an inverse model of the asymmetry rate-related control model, thereby effectively improving the accuracy and efficiency of compensating for the hysteresis characteristics.

[0058] Optionally, see Figure 4 , Figure 4 A detailed flow chart of step S210 is provided in an embodiment of the present application. Step S210 may include steps S211-S213.

[0059] Step S211 : determining a corresponding dead zone model based on the dead zone operator of the initial model.

[0060] Among them, when constructing the control model related to the asymmetry rate, considering that the traditional PI model cannot describe the asymmetric relationship of the actual hysteresis characteristics in the piezoelectric system, the corresponding dead zone model can be determined based on the dead zone operator of the initial model.

[0061] Optionally, considering that the initial model cannot describe the asymmetric relationship of the hysteresis characteristics in the actual system, a dead zone model can be introduced to improve the initial model. The dead zone model means that no output is generated within a certain range of the input signal. When the input signal exceeds this range, the dead zone model starts to generate output. The dead zone model is denoted as γ, and its output It is given by: ; in, represents the weight of the dead zone operator, Represents the threshold of the dead zone model. Usually, the positive and negative thresholds are symmetrical and pre-set. Represents the dead zone operator, which is based on the input and a pre-given threshold To determine the output, it is defined as: .

[0062] Step S212: determining a dynamic threshold that characterizes the hysteresis characteristic of the piezoelectric system based on the rate of change.

[0063] Among them, considering the influence of the input change rate on the hysteresis characteristic, the dynamic threshold that characterizes the hysteresis characteristic of the piezoelectric system can be determined.

[0064] Alternatively, considering that the initial model uses a fixed threshold, the effect of the input change rate on hysteresis is ignored. However, in real systems, the input signal change rate has a significant impact on hysteresis behavior. Therefore, the initial model can be improved by introducing a dynamic threshold to more accurately reflect the hysteresis characteristics of the actual system. The dynamic threshold is defined as follows: ; in, Indicates the dynamic threshold of the i-th operator, the input change rate function, is the dynamic threshold coefficient, Represents the basic threshold, which is linearly related to the operator number i. Used to describe the effect of input change rate on hysteresis.

[0065] Step S213 , adjusting the initial model according to the dead zone model and the dynamic threshold to obtain a control model related to the asymmetry rate.

[0066] Among them, the initial model can be adjusted and improved by combining the dead zone model and the dynamic threshold to obtain a control model related to the asymmetry rate.

[0067] Optionally, the improvement process of the initial model may include operator replacement and the like.

[0068] exist Figure 4 In the illustrated embodiment, the initial model can be improved by combining the dead zone model and the dynamic threshold, thereby effectively improving the accuracy of the control model in characterizing the hysteresis characteristic.

[0069] Optionally, see Figure 5 , Figure 5 A detailed flow chart of step S213 is provided in an embodiment of the present application. Step S213 may include steps S2131-S2133.

[0070] Step S2131 : replacing the initial model based on the dead zone model to obtain an optimized hysteresis operator.

[0071] Among them, the initial model can be replaced based on the dead zone model to obtain an improved optimized hysteresis operator.

[0072] Optionally, the hysteresis operator of the output model can be input Replaced by the output of the dead zone model γ , we can further get the optimized hysteresis operator : .

[0073] Step S2132: construct a process model based on the optimized hysteresis operator and the initial model.

[0074] Among them, the corresponding process model can be constructed according to the optimized hysteresis operator and the initial model.

[0075] Optionally, the process model constructed based on the optimized hysteresis operator and the initial model improvement may be a GPI model. The process model may include: .

[0076] Step S2133: Adjust the process model according to the dynamic threshold to obtain a control model.

[0077] Among them, considering that the process model usually adopts a fixed threshold, the influence of the input change rate on the hysteresis phenomenon is ignored. Therefore, the process model can be adjusted according to the dynamic threshold to obtain the corresponding control model.

[0078] Optionally, the constructed control model can be used to describe the hysteresis nonlinear behavior of the piezoelectric actuator. The specific expression is: It should be noted that the control model includes: ; in, represents the output of the control model, represents the input of the control model, represents the output of the dead zone model, and is the weight parameter, n is the total number of operators, represents the dynamic threshold of the i-th operator, Represents the RD-GPI model, that is, the control model.

[0079] exist Figure 5 In the illustrated embodiment, the initial model can be gradually improved according to the dead zone model and the dynamic threshold, thereby effectively improving the effectiveness and accuracy of the control model.

[0080] Optionally, the historical data may include multiple sets of associated input data and output data under historical working conditions of the piezoelectric system. For example, the piezoelectric ceramic actuator in the piezoelectric system may be collected under different input data. Voltage and displacement data under As the output data of the corresponding association.

[0081] See also Figure 6 , Figure 6 A detailed flow chart of step S220 is provided in an embodiment of the present application. Step S220 may include steps S221-S223.

[0082] In step S221 , multiple sets of input data and corresponding output data are substituted into the control model for calculation to obtain initial parameter ranges of model parameters in the control model.

[0083] The model parameters may include a first weight parameter (i.e. 、 ) and the dynamic threshold coefficient (i.e. When determining the target parameters in the control model, multiple sets of input data and output data can be substituted into the control model for calculation to obtain the initial parameter ranges of various types of model parameters in the control model.

[0084] Optionally, the initial parameter range can be a set of optimal parameter vectors Make the model output of the control model The actual measured output displacement data The error between them is minimized, and then the objective function can be defined Output for the model The actual measured output displacement data The sum of squared errors between , where T is the total number of data points, Indicates that the parameter The output of the control model at time t.

[0085] Step S222: determining physical constraints of the model parameters based on the operating parameters of the piezoelectric system.

[0086] Among them, considering the physical meanings of various model parameters, the physical constraints of the model parameters can be determined according to the working parameters of the piezoelectric system.

[0087] Optionally, the set physical constraint condition may include: the value of the dynamic threshold coefficient is a positive constant, and the physical constraint condition is converted into a linear inequality constraint form as follows: ; That is A , where A is the constraint matrix, b is the constraint vector, and the nonlinear inequality constraint function is expressed as c , the nonlinear equality constraint function is expressed as: .

[0088] Step S223: Determine the target parameters by combining the physical constraints and the initial parameter range.

[0089] The physical constraint conditions and the initial parameter range may be combined to perform screening processing, and the parameters that meet the physical constraint conditions within the initial parameter range may be determined as target parameters.

[0090] Optionally, during the parameter optimization process, an initial parameter guess value x_initial can be selected, which can be set based on prior knowledge or experience. In order to minimize the target, combined with the physical constraints, the parameter vector x is identified to obtain the optimal system parameter vector as the target parameter.

[0091] exist Figure 6 In the illustrated embodiment, the control model can be parameter-identified according to the actual conditions of the piezoelectric system, effectively improving the accuracy of the target parameters and the adaptability of the target parameters to the piezoelectric system, thereby improving the effectiveness of the control model.

[0092] See also Figure 7 , Figure 7 A detailed flowchart of step S230 is provided in an embodiment of the present application. Step S230 may include steps S231-S232.

[0093] Step S231 : performing an inverse solution on the control model using the target parameters to obtain inverse model parameters of the compensation model.

[0094] In the process of constructing the inverse model, the control model using the target parameters can be inversely solved to obtain various types of inverse model parameters corresponding to the inverse model. The inverse model parameters can include a second weight parameter and a threshold parameter.

[0095] Step S232: constructing a compensation model for performing feedforward compensation on the piezoelectric system based on the inverse model parameters.

[0096] Among them, a corresponding compensation model can be constructed based on the inverse model parameters to perform feed-forward compensation on the hysteresis characteristics of the piezoelectric system.

[0097] Alternatively, the construction of the RD-GPI inverse model is based on the RD-GPI model, which can be decomposed into a rate-dependent inverse model and dead zone inverse model The cascade composition can be based on the input Inverse model related to first choice pass rate , get the intermediate variable , and then through the dead zone inverse model , and finally get the output . The relationship can be expressed as: ; in, Represents the compensation model, intermediate variable The calculation process may include: ; in, is the threshold parameter of the compensation model, and is the weight parameter of the compensation model, is the hysteresis operator of the compensation model, and the specific calculation method is: ; Output of the compensation model for: ; in, is the threshold parameter of the inverse dead zone model, are the weights of the inverse dead zone model, is the dead zone operator, and its calculation formula is: .

[0098] According to the model parameters of the control model , the threshold parameters of the inverse model can be derived and calculated respectively ( and ) and the weight parameters ( and ), the specific formula is: ; =0,…,n-1; =0,1,…,m; =-m,…,-1; ; ; .

[0099] exist Figure 7In the illustrated embodiment, an inverse model of the control model can be constructed as a compensation model by analytical inverse processing, so as to perform feedforward compensation on the hysteresis characteristics of the piezoelectric system based on the compensation model, thereby improving the accuracy and efficiency of the feedforward compensation.

[0100] Optionally, see Figure 8 , Figure 8 A detailed flow chart of step S300 is provided in an embodiment of the present application. Step S300 may include steps S310-S330.

[0101] Step S310 : determining the error variable of the piezoelectric system according to the dynamic equation and state space expression of the piezoelectric system.

[0102] In order to improve the anti-interference capability of the piezoelectric system, an adaptive control algorithm for feedback compensation of the piezoelectric system can be determined. The error variable of the piezoelectric system can be determined based on the dynamic equation and state space expression of the piezoelectric system.

[0103] Alternatively, the dynamic equation of the piezoelectric system can be established as: ; in, represents the output of the piezoelectric system, represents the input of the piezoelectric system, is the system parameter, Indicates external disturbance.

[0104] make , the state space expression of the piezoelectric system can be obtained as: ; The tracking error can be defined as: ; in, is the desired output displacement, based on which the error variable e can be calculated: .

[0105] Step S320 : determining an adaptation rate of the piezoelectric system based on the control gain and the error variable of the piezoelectric system.

[0106] Among them, the adaptability rate of the piezoelectric system can be determined based on the gain system and the error variable.

[0107] Optionally, the control gain may include a fixed control gain and an adaptively adjusted control gain, the adaptive rate Calculation methods may include: ; , ; , ; ; represents the fixed control gain, represents the adaptively adjusted control gain, 、 is the design parameter, Indicates positional parameters The estimated value of .

[0108] Step S330 : determining an adaptive control algorithm for feedback compensation of the piezoelectric system according to the adaptive rate.

[0109] Among them, the adaptive control algorithm can be determined according to the adaptive rate to perform feedback compensation on the input of the piezoelectric system.

[0110] Optionally, an adaptive control algorithm , For unknown parameters estimated value.

[0111] Alternatively, to prove that the piezoelectric system is not oriented, the Lyapunov function can be defined as: ; ; in, , indicating The estimation error of , indicating the parameters The error estimate of .

[0112] The derivative of V is further calculated as: , we can calculate: ; Among them, the auxiliary variables , , , , .

[0113] In summary, , in order to prove the stability of the closed loop of the piezoelectric system, the closed loop system is bounded, that is, all state variables and parameter estimation errors remain bounded, and the error variables can eventually converge to an adjustable small enough neighborhood, specifically .

[0114] exist Figure 8In the illustrated embodiment, a corresponding adaptive control algorithm can be determined based on the stability requirements of the piezoelectric system to perform feedback compensation, thereby further reducing the impact of hysteresis characteristics on the piezoelectric system and improving the control accuracy of the piezoelectric system.

[0115] See also Figure 9 , Figure 9 A schematic structural diagram of a piezoelectric system hysteresis modeling and composite control device provided in an embodiment of the present application, wherein the piezoelectric system hysteresis modeling and composite control device 500 may include: a control system 510 and a piezoelectric system 520; The control system 510 includes a feedforward controller 511 and a feedback controller 512. The feedforward controller 511 is provided with a compensation model for performing feedforward compensation on the piezoelectric system 520. The feedback controller 512 is provided with an adaptive control algorithm for performing feedback compensation on the piezoelectric system 520. The feedforward controller 511 is connected to the input terminal of the piezoelectric system 520 , and the feedback controller 512 is connected to the input terminal and the output terminal of the piezoelectric system 520 ; A feedforward controller 511 is configured to perform feedforward compensation and determine a feedforward control amount; A feedback controller 512 is configured to perform feedback compensation and determine a feedback control amount; The control system 510 is used to determine the input control quantity of the piezoelectric system 520 according to the feedforward control quantity and the feedback control quantity.

[0116] In an optional embodiment, the method for constructing the compensation model in the feedforward controller 511 includes: constructing an asymmetric rate-related control model based on an initial model; wherein the initial model includes a PI model, and the control model includes a rate-related asymmetric generalized PI model; determining the target parameters of the control model based on the historical data of the piezoelectric system 520; and inversely processing the control model using the target parameters to obtain a compensation model for feedforward compensation of the piezoelectric system 520.

[0117] In an optional embodiment, the method for constructing the compensation model in the feedforward controller 511 specifically includes: determining the corresponding dead zone model based on the dead zone operator of the initial model; determining the dynamic threshold that characterizes the hysteresis characteristics of the piezoelectric system 520 based on the rate of change; and adjusting the initial model according to the dead zone model and the dynamic threshold to obtain a control model related to the asymmetry rate.

[0118] In an optional embodiment, the method for constructing the compensation model in the feedforward controller 511 specifically includes: replacing the initial model based on the dead zone model to obtain an optimized hysteresis operator; constructing a process model based on the optimized hysteresis operator and the initial model; wherein the process model includes a GPI model; and adjusting the process model based on a dynamic threshold to obtain a control model, wherein the control model includes: ;in, represents the output of the control model, represents the input of the control model, represents the output of the dead zone model, and is the weight parameter, n is the total number of operators, represents the dynamic threshold of the i-th operator.

[0119] In an optional embodiment, the historical data includes correlated input data and output data; the method for constructing the compensation model in the feedforward controller 511 specifically includes: substituting multiple sets of input data and corresponding output data into the control model for calculation to obtain the initial parameter range of the model parameters in the control model; wherein the model parameters include the first weight parameter and dynamic threshold coefficient of the control model; based on the working parameters of the piezoelectric system 520, determining the physical constraints of the model parameters; and determining the target parameters in combination with the physical constraints and the initial parameter range.

[0120] In an optional embodiment, the method for constructing the compensation model in the feedforward controller 511 specifically includes: performing an inverse solution on the control model using the target parameters to obtain the inverse model parameters of the compensation model; wherein the inverse model parameters include a second weight parameter and a threshold parameter; based on the inverse model parameters, constructing a compensation model for feedforward compensation of the piezoelectric system 520.

[0121] In an optional embodiment, the method for determining the adaptive control algorithm in the feedback controller 512 includes: determining the error variable of the piezoelectric system 520 based on the dynamic equation and state space expression of the piezoelectric system 520; determining the adaptive rate of the piezoelectric system 520 based on the control gain and error variable of the piezoelectric system 520; and determining the adaptive control algorithm for feedback compensation of the piezoelectric system 520 based on the adaptive rate.

[0122] Since the principle of solving the problem by the piezoelectric system hysteresis modeling and composite control device 500 in the embodiment of the present application is similar to that in the aforementioned embodiment of the piezoelectric system hysteresis modeling and composite control method, the implementation of the piezoelectric system hysteresis modeling and composite control device 500 in this embodiment can refer to the description in the aforementioned embodiment of the piezoelectric system hysteresis modeling and composite control method, and the repeated parts will not be repeated.

[0123] An embodiment of the present application also provides an electronic device, which includes a memory and a processor. The memory stores program instructions. When the processor reads and runs the program instructions, it executes the steps of any one of the piezoelectric system hysteresis modeling and composite control methods provided in this embodiment.

[0124] An embodiment of the present application also provides a computer program product, which includes a computer program / instructions. When the computer program / instructions are executed by a processor, the steps of any one of the piezoelectric system hysteresis modeling and composite control methods provided in this embodiment are implemented.

[0125] In the several embodiments provided in this application, it should be understood that the disclosed devices can also be implemented in other ways. The device embodiments described above are merely schematic. For example, the block diagrams in the accompanying drawings show the possible architecture, functions and operations of the devices according to the multiple embodiments of the present application. In this regard, each box in the block diagram can represent a module, a program segment or a part of a code, and the module, program segment or a part of the code contains one or more executable instructions for implementing the specified logical functions. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram, and the combination of the block diagrams, can be implemented with a dedicated hardware-based system that performs the specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0126] In addition, the functional modules in each embodiment of the present application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0127] If the functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a number of instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard drives, read-only memories (ROM), random access memories (RAM), magnetic disks or optical disks.

[0128] The foregoing is merely an embodiment of the present application and is not intended to limit the scope of protection of the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application shall be included within the scope of protection of the present application. It should be noted that similar reference numerals and letters represent similar items in the following figures. Therefore, once an item is defined in one figure, it does not need to be further defined or explained in subsequent figures.

[0129] The above is only a specific implementation method of the present application, but the scope of protection of the present application is not limited thereto. Any technician familiar with this technical field can easily think of changes or replacements within the technical scope disclosed in this application, which should be covered by the scope of protection of the present application.

[0130] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, the elements defined by the phrase "comprising..." do not exclude the presence of other identical elements in the process, method, article, or device comprising the elements.

Claims

1. A piezoelectric system hysteresis modeling and composite control method, characterized in that: The method comprises: Constructing a compensation model for feedforward compensation of the piezoelectric system; wherein the compensation model is an inverse model of the asymmetry rate-related control model; determining an adaptive control algorithm for feedback compensation of the piezoelectric system; The input control amount of the piezoelectric system is determined by performing feedforward compensation based on the compensation model and the feedback control amount based on the adaptive control algorithm.

2. The method according to claim 1, characterized in that The constructing of a compensation model for performing feedforward compensation on a piezoelectric system includes: Constructing the asymmetric rate-dependent control model based on the initial model; wherein the initial model includes a PI model, and the control model includes a rate-dependent asymmetric generalized PI model; determining target parameters of the control model based on historical data of the piezoelectric system; The control model using the target parameters is inversely processed to obtain the compensation model for feed-forward compensation of the piezoelectric system.

3. The method according to claim 2, characterized in that The control model related to the asymmetric rate is constructed based on the initial model, comprising: Determining a corresponding dead zone model based on the dead zone operator of the initial model; determining a dynamic threshold value characterizing a hysteresis characteristic of the piezoelectric system based on the rate of change; The initial model is adjusted according to the dead zone model and the dynamic threshold to obtain the control model related to the asymmetry rate.

4. The method according to claim 3, characterized in that The adjusting the initial model according to the dead zone model and the dynamic threshold to obtain the control model related to the asymmetry rate includes: The initial model is replaced based on the dead zone model to obtain an optimized hysteresis operator; Constructing a process model according to the optimized hysteresis operator and the initial model; wherein the process model includes a GPI model; The process model is adjusted according to the dynamic threshold to obtain the control model, which includes: ; in, represents the output of the control model, represents the input of the control model, represents the output of the dead zone model, and is the weight parameter, n is the total number of operators, represents the dynamic threshold of the i-th operator.

5. The method according to claim 2, characterized in that in, The historical data includes associated input data and output data; The determining the target parameters of the control model based on the historical data of the piezoelectric system includes: Substituting multiple sets of the input data and the corresponding output data into the control model for calculation, thereby obtaining an initial parameter range of the model parameters in the control model; wherein the model parameters include a first weight parameter and a dynamic threshold coefficient of the control model; Determining physical constraints of the model parameters based on operating parameters of the piezoelectric system; The target parameter is determined by combining the physical constraint condition and the initial parameter range.

6. The method according to claim 2, characterized in that The inverse processing of the control model using the target parameters to obtain the compensation model for performing feedforward compensation on the piezoelectric system includes: Performing an inverse solution on the control model using the target parameter to obtain inverse model parameters of the compensation model; wherein the inverse model parameters include a second weight parameter and a threshold parameter; Based on the inverse model parameters, the compensation model for performing feed-forward compensation on the piezoelectric system is constructed.

7. The method according to claim 1, characterized in that The determining of an adaptive control algorithm for feedback compensation of the piezoelectric system comprises: determining an error variable of the piezoelectric system according to a dynamic equation and a state-space expression of the piezoelectric system; determining an adaptation rate of the piezoelectric system based on a control gain of the piezoelectric system and the error variable; The adaptive control algorithm for performing feedback compensation on the piezoelectric system is determined according to the adaptive rate.

8. A piezoelectric system hysteresis modeling and composite control device, characterized in that: The device includes: a control system and a piezoelectric system; The control system includes a feedforward controller and a feedback controller, the feedforward controller is provided with a compensation model for performing feedforward compensation on the piezoelectric system, and the feedback controller is provided with an adaptive control algorithm for performing feedback compensation on the piezoelectric system; The feedforward controller is connected to the input end of the piezoelectric system, and the feedback controller is connected to the input end and the output end of the piezoelectric system; The feedforward controller is used to perform feedforward compensation and determine the feedforward control amount; The feedback controller is used to perform feedback compensation to determine the feedback control amount; The control system is used to determine the input control quantity of the piezoelectric system based on the feedforward control quantity and the feedback control quantity.

9. An electronic device, characterized in that: The electronic device includes a memory and a processor, wherein program instructions are stored in the memory, and when the processor runs the program instructions, the steps of the method according to any one of claims 1 to 7 are executed.

10. A computer program product, characterized in that The computer program product comprises a computer program / instruction, and when the computer program / instruction is executed by a processor, the steps in the method according to any one of claims 1 to 7 are implemented.

Images