Dynamic polarization method and device for preparing high-consistency piezoelectric film

Abstract

The invention discloses a dynamic polarization method and device for preparing a high-consistency piezoelectric film, and relates to the field of piezoelectric film polarization. In the first step of melt extrusion sheet preparation of the piezoelectric film, the influence of inconsistent thickness of each part of the piezoelectric film on polarization is considered; the piezoelectric film is polarized by adopting different polarization voltages for different positions of the film, so that the problems that the piezoelectric film at a relatively thick position is not polarized in place and the piezoelectric film at a relatively thin position is easy to break down are solved; the polarization voltage is adjusted in real time according to the actual polarization state of each part of the thin film; the polarization effect of the piezoelectric film is monitored online in real time, effective feedback and correction are generated in the polarization process, and the polarization effect is guaranteed.

Description

Technical Field

[0001] The present invention belongs to the field of piezoelectric thin film polarization. Specifically, it particularly relates to a dynamic polarization method and device for preparing piezoelectric thin films with high consistency. Background Art

[0002] Patent CN100416881C discloses an "ordered orientation device for polymer piezoelectric materials"; it involves a device and method for continuously polarizing a piezoelectric thin film. The technical solution is as follows: while stretching and orienting the piezoelectric thin film, corona polarization treatment is carried out to complete stretching and polarization synchronously; the corona polarization part mainly includes a planar aluminum plate laid on the back of the organic piezoelectric thin film, connected to the ground terminal of the high-voltage power supply, and a needle-like array electrode installed at a certain distance above the upper surface of the piezoelectric thin film, connected to the high-voltage output terminal of the power supply. By applying a high voltage to the needle electrode array, polarization treatment of the organic piezoelectric thin film is achieved.

[0003] Patent CN111554801A proposes an "organic piezoelectric thin film continuous polarization method". The technical solution is as follows: an organic piezoelectric thin film without electrodes is closely attached to the upper surface of a zero electrode roller connected to the ground terminal of the high-voltage polarization power supply under the action of front and rear guide rollers, pressing rollers, and traction rollers. A wire electrode spanning the organic piezoelectric thin film and connected to the high-voltage output terminal of the high-voltage polarization power supply is installed at a certain distance above the organic piezoelectric thin film as a corona electrode; an infrared heating lamp is provided on one side or above the corona electrode to heat the organic piezoelectric thin film; the organic piezoelectric thin film is continuously driven by a traction device to pass through the polarization electric field below the corona electrode to achieve continuous polarization of the organic piezoelectric thin film.

[0004] When the piezoelectric thin film is prepared by melt extrusion and sheet making in the first step, due to the extrusion accuracy limitation of the extrusion die head, there is uneven thickness in the transverse direction (perpendicular to the extrusion direction) of the thin film. Therefore, when the extruded sheet is stretched subsequently, the stretched piezoelectric thin film also has uneven thickness, and the stretching film used for polarization also has uneven thickness. When polarizing the piezoelectric thin film in the above two technical solutions, the influence of the inconsistent thickness of the piezoelectric thin film at each part on polarization is not considered, and the piezoelectric thin film is polarized by the same polarization voltage at each part. This results in incomplete polarization of the piezoelectric thin film at the thicker position, and the piezoelectric thin film at the thinner position is easily broken down. There is a lack of real-time adjustment of the polarization voltage, and the voltage remains unchanged during the polarization process of all corona electrodes, and no adjustment can be made according to the actual polarization state of each part of the thin film. In addition, in the past technical solutions, there is no real-time online monitoring of the polarization effect of the piezoelectric thin film, and the polarization quality depends on off-line detection, and no effective feedback and correction can be made to the polarization process. Moreover, the temperature control method of the above technical solutions is unreliable, the infrared heating lamp cannot uniformly heat the thin film, and the local temperature difference will affect the polarization uniformity. At the same time, the adjustment of the speed parameter in the above solution lacks flexibility, and the polarization speed is not adjusted in combination with the voltage, temperature and actual polarization effect. Summary of the Invention

[0005] In view of the problems in the related art, the present invention proposes a dynamic polarization method and device for preparing piezoelectric thin films with high consistency to overcome the above-mentioned technical problems existing in the existing related technologies.

[0006] To solve the above technical problems, the present invention is realized through the following technical solutions:

[0007] The present invention is a dynamic polarization method for preparing piezoelectric thin films with high consistency, including the following steps:

[0008] S1. Collect the temperature data of the piezoelectric thin film to be polarized on the first polarization roller and the second polarization roller and adjust it in combination with the standard polarization temperature to obtain the first polarization temperature data and the second polarization temperature data;

[0009] S2. Measure the thickness data and β-phase content data at each data acquisition point on the piezoelectric thin film to be polarized to obtain the dataset of the thickness of the piezoelectric thin film to be polarized and the dataset of the β-phase content of the piezoelectric thin film to be polarized; perform a boosting operation on the first corona electrode array and the second corona electrode array;

[0010] S3. Measure the β-phase dipole orientation data of the piezoelectric thin film to be polarized to obtain the β-phase dipole orientation data of the piezoelectric thin film to be polarized; then, in combination with the dataset of the thickness of the piezoelectric thin film to be polarized and the dataset of the β-phase content of the piezoelectric thin film to be polarized, adjust the voltage value of each array unit of the first corona electrode array in real time and perform a polarization operation on the piezoelectric thin film to be polarized to obtain the piezoelectric thin film after primary polarization;

[0011] S4. Collect the piezoelectric performance data of multiple data acquisition points on the piezoelectric film after the first polarization, adjust the voltage value of each array unit of the second corona electrode array, and perform a second polarization on the piezoelectric film after the first polarization to obtain a piezoelectric film after the second polarization;

[0012] Preferably, the S1 includes the following steps:

[0013] S11. Set the unwind roller, the wind-up roller, the first polarization roller, the second polarization roller, and the piezoelectric film to be polarized; use a temperature sensor to collect the temperature data of the piezoelectric film to be polarized on the first polarization roller and the second polarization roller;

[0014] S12. Set the standard polarization temperature; when the temperature data of the piezoelectric film to be polarized on the first polarization roller and the second polarization roller is less than the standard polarization temperature, perform a heating operation on the piezoelectric film to be polarized until the temperature data of the piezoelectric film to be polarized on the first polarization roller and the second polarization roller collected in S11 are both greater than or equal to the standard polarization temperature, and obtain the first polarization temperature data and the second polarization temperature data;

[0015] Preferably, the S2 includes the following steps:

[0016] S21. Set a plurality of data acquisition points on the piezoelectric film to be polarized to obtain a piezoelectric film data acquisition point set; in cooperation with the piezoelectric film data acquisition point set, use a laser thickness gauge to measure the thickness data of each data acquisition point on the piezoelectric film to be polarized to obtain a piezoelectric film to be polarized thickness data set; then use a WXRD device to measure the β-phase content data of each data acquisition point on the piezoelectric film to be polarized to obtain a piezoelectric film to be polarized β-phase content data set;

[0017] S22. Set the first corona electrode array, the second corona electrode array, and the standard polarization voltage; perform a boosting operation on the first corona electrode array and the second corona electrode array until the voltages of the first corona electrode array and the second corona electrode array reach the standard polarization voltage;

[0018] Preferably, the S3 includes the following steps:

[0019] S31. Adjust the rotation speeds of the unwind roller, the first polarization roller, the second polarization roller, and the wind-up roller according to the tension of the piezoelectric film to be polarized attached to the first polarization roller and the second polarization roller until the piezoelectric film to be polarized is tightly attached to the first polarization roller and the second polarization roller;

[0020] S32. Measure the β-phase dipole orientation data in the lateral direction of the piezoelectric thin film to be polarized using a WXRD device, and obtain the β-phase dipole orientation data of the piezoelectric thin film to be polarized; in combination with the thickness data set of the piezoelectric thin film to be polarized, the β-phase content data set of the piezoelectric thin film to be polarized, and the β-phase dipole orientation data of the piezoelectric thin film to be polarized, adjust the voltage value of each array unit (needle electrode) of the first corona electrode array in real time. After the adjustment is completed, perform a polarization operation on the piezoelectric thin film to be polarized to obtain a once-polarized piezoelectric thin film;

[0021] Preferably, in S32, in combination with the thickness data set of the piezoelectric thin film to be polarized, the β-phase content data set of the piezoelectric thin film to be polarized, and the β-phase dipole orientation data of the piezoelectric thin film to be polarized, the real-time adjustment of the voltage value of each array unit of the first corona electrode array includes the following steps:

[0022] S321. Collect the average thickness data, average β-phase content data, β-phase dipole orientation data, and corresponding applied voltage data of the piezoelectric thin film during the polarization process of multiple groups of piezoelectric thin films under standard conditions in history, and obtain a historical piezoelectric thin film thickness data set, a historical piezoelectric thin film β-phase content data set, a historical piezoelectric thin film β-phase dipole orientation data set, and a first historical applied voltage data set;

[0023] S322. Construct a first applied voltage mapping model using the historical piezoelectric thin film thickness data set, the historical piezoelectric thin film β-phase content data set, the historical piezoelectric thin film β-phase dipole orientation data set, and the first historical applied voltage data set;

[0024] S323. In combination with the first applied voltage mapping model, adjust the voltage value of each array unit of the first corona electrode array in real time to obtain a first array unit voltage data set;

[0025] S324. In combination with the first array unit voltage data set, use the first corona electrode array to perform a primary polarization operation on the piezoelectric thin film to be polarized on the first polarization roller; after the primary polarization operation is completed, obtain a once-polarized piezoelectric thin film;

[0026] Preferably, S322 includes the following steps:

[0027] S3221. Construct a mapping equation between the piezoelectric thin film thickness data, the piezoelectric thin film β-phase content data, the piezoelectric thin film β-phase dipole orientation data, and the applied voltage data to obtain an initial applied voltage mapping equation;

[0028] S3222. Substitute the historical piezoelectric thin film thickness data set, the historical piezoelectric thin film β-phase content data set, and the historical piezoelectric thin film β-phase dipole orientation data set into the initial applied voltage mapping equation for mapping to obtain a historical initial applied voltage mapping data set;

[0029] S3223. Set the threshold of the applied voltage mapping error; calculate the error data between the historical initial applied voltage mapping data set and the first historical applied voltage data set to obtain the historical initial mapping error data of the applied voltage;

[0030] When the historical initial mapping error data of the applied voltage is greater than or equal to the threshold of the applied voltage mapping error, adjust the initial applied voltage mapping equation until the historical initial mapping error data of the applied voltage is less than the threshold of the applied voltage mapping error or until the historical initial mapping error data of the applied voltage is greater than or equal to the threshold of the applied voltage mapping error, and obtain the final applied voltage mapping equation; otherwise, there is no need to adjust the initial applied voltage mapping equation, and use the initial applied voltage mapping equation as the final applied voltage mapping equation;

[0031] Preferably, the adjustment of the initial applied voltage mapping equation in S3223 includes the following steps:

[0032] S32231. Set the value range of each independent variable coefficient, independent variable exponent coefficient, and bias parameter in the initial applied voltage mapping equation to obtain the set of value ranges of independent variable coefficients, the set of value ranges of independent variable exponent coefficients, and the value range of bias parameters;

[0033] Construct an adjusted Tianying population for the applied voltage mapping; set the maximum number of iterations of the adjusted Tianying population for the applied voltage mapping as b1' and the current number of iterations as b2', which are respectively denoted as the maximum number of iterations of the voltage mapping and the current number of iterations of the voltage mapping; the search space dimension of the adjusted Tianying population for the applied voltage mapping is 7 - dimensional;

[0034] S32232. Generate the initial position of each Tianying in the adjusted Tianying population for the applied voltage mapping according to the set of value ranges of independent variable coefficients, the set of value ranges of independent variable exponent coefficients, and the value range of bias parameters to obtain a set of initial position matrices;

[0035] S32233. Construct the fitness function of the adjusted Tianying population for the applied voltage mapping;

[0036] S32234. Start iteration. Before iteration, set the current iteration number of the voltage mapping to 1. During the first-round iteration, use the applied voltage mapping to adjust the fitness function c of the eagle population to calculate the fitness values of the initial position matrices of each eagle in the initial position matrix set, obtaining the first fitness value set. Take the maximum fitness value in the first fitness value set and the corresponding initial position of the eagle as the first global best fitness and the first global best position respectively. Update the initial position matrices of each eagle in the initial position matrix set according to the first global best fitness and the first global best position. After the update is completed, increment the current iteration number of the voltage mapping by 1 and perform the next round of iteration.

[0037] During each subsequent round of iteration, use the applied voltage mapping to adjust the fitness function of the eagle population to calculate the fitness values of the position matrices of each eagle in the applied voltage mapping-adjusted eagle population updated in the previous round of iteration, obtaining the second fitness value set. Take the maximum fitness value in the second fitness value set and the corresponding position of the eagle as the second global best fitness and the second global best position respectively. Update the position matrices of each eagle in the applied voltage mapping-adjusted eagle population updated in the previous round of iteration according to the second global best fitness and the second global best position. After the update is completed, increment the current iteration number of the voltage mapping by 1 and perform the next round of iteration.

[0038] S32235. When b2′≥b1′, stop iteration to obtain the final global best fitness and the final global best position; otherwise, continue iteration until b2′≥b1′. Take the final global best fitness as the historical optimized initial applied voltage mapping error data. When the historical optimized initial applied voltage mapping error data is less than the applied voltage mapping error threshold, the adjustment is completed to obtain the final applied voltage mapping equation; otherwise, return to S32234 to continue iteration until the historical optimized initial applied voltage mapping error data is less than the applied voltage mapping error threshold.

[0039] The eagle optimization algorithm can effectively jump out of the local optimal solution in the extended exploration stage by simulating the behaviors of eagles such as vertical bending flight and short gliding attacks, and is particularly suitable for dealing with multi-dimensional parameter optimization problems containing non-linear terms (such as exponential coefficients). Based on the above advantages, in this solution, the eagle optimization algorithm is used to perform multiple iterative optimizations on the independent variable coefficients, independent variable exponential coefficients, and bias parameters of the initial applied voltage mapping equation, and the mapping accuracy of the initial applied voltage mapping equation is used as the fitness function. Therefore, as the iteration progresses, the mapping accuracy of the initial applied voltage mapping equation becomes higher and higher, and finally meets the mapping requirements.

[0040] Preferably, S323 includes the following steps:

[0041] S3231. Obtain and calculate the average thickness data and average β-phase content data of the piezoelectric thin film regions corresponding to each array unit of the first corona electrode array in coordination with the dataset of the thickness of the piezoelectric thin film to be polarized and the dataset of the β-phase content of the piezoelectric thin film to be polarized, so as to obtain the dataset of the thickness of the first piezoelectric thin film region to be polarized and the dataset of the β-phase content of the first piezoelectric thin film region to be polarized;

[0042] S3232. Input each data in the dataset of the thickness of the first piezoelectric thin film region to be polarized, the dataset of the β-phase content of the first piezoelectric thin film region to be polarized, and the data of the β-phase dipole orientation of the piezoelectric thin film to be polarized into the final applied voltage mapping equation for mapping to obtain the dataset of the voltages of the first array unit;

[0043] Preferably, the S4 includes the following steps:

[0044] S41. Collect the piezoelectric performance data at each data collection point on the piezoelectric thin film after one-time polarization in coordination with the piezoelectric thin film data collection point set to obtain the dataset of the piezoelectric performance after one-time polarization;

[0045] S42. Set the uniform threshold of the piezoelectric performance after one-time polarization; calculate the variance data of the dataset of the piezoelectric performance after one-time polarization to obtain the variance data of the piezoelectric performance after one-time polarization; when the variance data of the piezoelectric performance after one-time polarization is greater than or equal to the uniform threshold of the piezoelectric performance after one-time polarization, respectively use each voltage data in the dataset of the voltages of the first array unit as the voltage data of each array unit in the second corona electrode array; otherwise, adjust the voltage data of each array unit in the second corona electrode array and perform secondary polarization on the piezoelectric thin film after one-time polarization to obtain the piezoelectric thin film after secondary polarization;

[0046] S43. Set the repetition number threshold; repeat S1, S2, S3, S41, and S42 for the piezoelectric thin film after secondary polarization in coordination with the repetition number threshold.

[0047] Preferably, the adjustment of the voltage data of each array unit in the second corona electrode array in S42 includes the following steps:

[0048] S421. Collect the piezoelectric performance data of the piezoelectric thin film before the polarization operation on the piezoelectric thin film under standard conditions in several groups in history and the corresponding applied voltage data to obtain the historical piezoelectric performance dataset and the historical second applied voltage dataset;

[0049] S422. Construct an initial SVM model and set the training data ratio; divide the historical piezoelectric property dataset and the historical second applied voltage dataset according to the training data ratio to obtain a historical piezoelectric property training dataset, a historical second applied voltage training dataset, a historical piezoelectric property test dataset, and a historical second applied voltage test dataset;

[0050] Then set the training error threshold; input the historical piezoelectric property training dataset as training data and the historical second applied voltage training dataset as training labels into the initial SVM model for training; during the training process, when the training error is less than the training error threshold, stop training to obtain a trained SVM model; otherwise, continue training until the training error is less than the training error threshold.

[0051] Set the test accuracy threshold; input the historical piezoelectric property test dataset as test data and the historical second applied voltage test dataset as test labels into the trained SVM model for testing; after testing, obtain the test accuracy data; when the test accuracy data is greater than or equal to the test accuracy threshold, use the trained SVM model as the performance-related applied voltage mapping model; otherwise, continue training the trained SVM model until the test accuracy data is greater than or equal to the test accuracy threshold.

[0052] S423. Input the data in the piezoelectric property dataset after the first polarization into the performance-related applied voltage mapping model for mapping to obtain a second array unit voltage dataset; adjust the voltage value of each array unit of the second corona electrode array in coordination with the second array unit voltage dataset.

[0053] A dynamic polarization system for preparing piezoelectric thin films with high consistency, comprising a temperature acquisition module for the piezoelectric thin film to be polarized, a temperature adjustment module for polarizing the piezoelectric thin film, a first data acquisition module for the piezoelectric thin film to be polarized, a voltage boosting module for the corona electrode array, a second data acquisition module for the piezoelectric thin film to be polarized, a first voltage adjustment module for the corona electrode array unit, a piezoelectric property data acquisition module, and a second voltage adjustment module for the corona electrode array unit;

[0054] The temperature acquisition module for the piezoelectric thin film to be polarized acquires the temperature data of the piezoelectric thin film to be polarized on the first polarization roller and the second polarization roller to obtain the first polarization temperature data and the second polarization temperature data;

[0055] The temperature adjustment module for polarizing the piezoelectric thin film adjusts the first polarization temperature data and the second polarization temperature data in coordination with the standard polarization temperature;

[0056] The first data acquisition module for the piezoelectric film to be polarized measures the thickness data and the β-crystal content data at each data acquisition point on the piezoelectric film to be polarized, and obtains a thickness data set of the piezoelectric film to be polarized and a β-crystal content data set of the piezoelectric film to be polarized;

[0057] The corona electrode array boost module performs a boost operation on the first corona electrode array and the second corona electrode array in cooperation with the standard polarization voltage;

[0058] The second piezoelectric film to be polarized data acquisition module measures the β-crystal phase dipole orientation data of the piezoelectric film to be polarized to obtain the β-crystal phase dipole orientation data of the piezoelectric film to be polarized;

[0059] The first corona electrode array unit voltage adjustment module adjusts the voltage value of each array unit of the first corona electrode array in real time according to the β-crystal dipole orientation data of the piezoelectric film to be polarized, the thickness data set of the piezoelectric film to be polarized, and the β-crystal content data set of the piezoelectric film to be polarized, and performs a polarization operation on the piezoelectric film to be polarized, to obtain a piezoelectric film after primary polarization;

[0060] The piezoelectric performance data collection module collects piezoelectric performance data of multiple data collection points on the piezoelectric film after primary polarization to obtain a piezoelectric performance data set after primary polarization;

[0061] The second corona electrode array unit voltage adjustment module adjusts the voltage value of each array unit of the second corona electrode array in cooperation with the piezoelectric performance data set after primary polarization and performs secondary polarization on the piezoelectric film after primary polarization to obtain the piezoelectric film after secondary polarization.

[0062] The present invention has the following beneficial effects:

[0063] 1. In the present invention, the piezoelectric film is prepared by melt extrusion in the first step of preparation, and the effect of inconsistent thickness of the piezoelectric film at different locations on polarization is taken into consideration. The piezoelectric film is polarized by using different polarization voltages at different locations of the film, thereby avoiding the problem of inadequate polarization of the piezoelectric film at thicker locations and easy breakdown of the piezoelectric film at thinner locations.

[0064] 2. In the present invention, the polarization voltage is adjusted in real time according to the actual polarization state of each part of the film; the polarization effect of the piezoelectric film is monitored online in real time, and effective feedback and correction are generated for the polarization process, thereby ensuring the polarization effect.

[0065] 3. In the present invention, the polarization speed is adjusted by combining voltage, temperature and actual polarization effect, so that the film can be heated uniformly, avoiding the problem that the local temperature difference will affect the polarization uniformity.

[0066] Of course, it is not necessary for any product implementing the present invention to achieve all the above-mentioned advantages simultaneously. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] In order to more clearly illustrate the technical solutions of the embodiments of the invention, the following will briefly introduce the drawings required for describing the embodiments. Obviously, the drawings in the following description are only some embodiments of the invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0068] Figure 1 It is a schematic flow chart of a dynamic polarization method for preparing a highly consistent piezoelectric thin film according to the present invention;

[0069] Figure 2 It is a schematic flow chart of the present invention for real-time adjustment of the voltage value of each array unit of the first corona electrode array;

[0070] Figure 3 It is a schematic module diagram of a dynamic polarization system for preparing a highly consistent piezoelectric thin film according to the present invention;

[0071] Figure 4 It is a schematic structural diagram of the present invention when the corona electrode array is separated from the polarization roller in the polarization device;

[0072] Figure 5 It is a schematic structural diagram of the present invention when the corona electrode array is attached to the polarization roller in the polarization device. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0073] The following will clearly and completely describe the technical solutions in the embodiments of the invention with reference to the drawings in the embodiments of the invention. Obviously, the described embodiments are only some embodiments of the invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the invention without creative efforts belong to the scope of protection of the invention.

[0074] Embodiment 1

[0075] Please refer to Figure 1-2 and Figure 4-5 , this embodiment is a dynamic polarization method for preparing a highly consistent piezoelectric thin film, including the following steps:

[0076] (1) Assemble a piezoelectric thin film polarization device, including a polarization module, a first measurement module, a second measurement module, and a control system module. The polarization module includes a unwind roller, a first guiding roller, a first polarization roller, a second guiding roller, a third guiding roller, a second polarization roller, a fourth guiding roller, a winding roller, and a servo motor arranged in sequence from front to back. The above components form a piezoelectric thin film transmission system. The polarization module further includes a first corona electrode array, a second corona electrode array, a high-voltage polarization power supply, and a temperature control component. The first measurement module includes a number of laser thickness gauges arranged along the transverse direction of the thin film and a wide-angle X-ray diffraction (WXRD) device. The first measurement module is located between the unwind roller and the first guiding roller. The second measurement module includes a wide-angle X-ray diffraction (WXRD) device, and this module is located between the second guiding roller and the third guiding roller. The control system module includes a motion control module, a voltage closed-loop regulation module, and a temperature control module.

[0077] (2) Install the piezoelectric thin film to be polarized onto the piezoelectric thin film transmission system and start all modules;

[0078] (3) The temperature sensors of the temperature control component detect the temperature of the piezoelectric thin film at the positions of the first and second polarization rollers, and the data is transmitted back to the temperature control module. If the temperature of the thin film is lower than the set polarization temperature, the heating component is started to heat the thin film;

[0079] S1. Collect the temperature data of the piezoelectric thin film to be polarized on the first polarization roller and the second polarization roller and adjust it in combination with the standard polarization temperature to obtain the first polarization temperature data and the second polarization temperature data;

[0080] The S1 includes the following steps:

[0081] S11. Set the unwind roller, winding roller, first polarization roller, second polarization roller, and the piezoelectric thin film to be polarized; use temperature sensors to collect the temperature data of the piezoelectric thin film to be polarized on the first polarization roller and the second polarization roller;

[0082] S12. Set the standard polarization temperature; when the temperature data of the piezoelectric thin film to be polarized on the first polarization roller and the second polarization roller is less than the standard polarization temperature, perform a heating operation on the piezoelectric thin film to be polarized until the temperature data of the piezoelectric thin film to be polarized on the first polarization roller and the second polarization roller collected in S11 is greater than or equal to the standard polarization temperature, and obtain the first polarization temperature data and the second polarization temperature data;

[0083] (4) After the thin film is heated to the polarization temperature, the first measurement module starts to operate. The laser thickness gauges measure the thickness of each position in the transverse direction of the current thin film, and the WXRD measures the β-phase content of each position in the transverse direction. The measured data is transmitted back to the voltage closed-loop regulation module, and the module processes and analyzes the data, and then regulates the voltage boost of the first and second corona electrode arrays;

[0084] S2. Measure the thickness data and β-phase content data at each data acquisition point on the piezoelectric thin film to be polarized, obtaining the thickness data set of the piezoelectric thin film to be polarized and the β-phase content data set of the piezoelectric thin film to be polarized; perform a boosting operation on the first corona electrode array and the second corona electrode array;

[0085] The S2 includes the following steps:

[0086] S21. Set a number of data acquisition points on the piezoelectric thin film to be polarized, obtaining the data acquisition point set of the piezoelectric thin film; in cooperation with the data acquisition point set of the piezoelectric thin film, use a laser thickness gauge to measure the thickness data at each data acquisition point on the piezoelectric thin film to be polarized, obtaining the thickness data set of the piezoelectric thin film to be polarized; then use a WXRD device to measure the β-phase content data at each data acquisition point on the piezoelectric thin film to be polarized, obtaining the β-phase content data set of the piezoelectric thin film to be polarized;

[0087] S22. Set the first corona electrode array, the second corona electrode array, and the standard polarization voltage; perform a boosting operation on the first corona electrode array and the second corona electrode array until the voltages of the first corona electrode array and the second corona electrode array reach the standard polarization voltage;

[0088] (5) After the corona electrode is boosted to the polarization voltage, the motion control module controls the start of the piezoelectric thin film drive system, adjusts the rotation speeds of the unwind roller, the polarization roller, and the windup roller according to the tension of the film attached to the polarization roller until the film tightly adheres to the polarization roller;

[0089] (6) The film continues to move and enters the second measurement module. The WXRD device measures the β-phase dipole orientation in the transverse direction of the film. The WXRD transmits the measured β-phase orientation situation of the film back to the voltage closed-loop regulation module. The regulation module comprehensively considers the film thickness and β-phase content data of the first measurement module and the dipole orientation data of the second measurement module. After calculation and correction by the algorithm, it adjusts the voltage value of each array unit (needle electrode) of the first corona electrode array in real time;

[0090] S3. Measure the β-phase dipole orientation data of the piezoelectric thin film to be polarized, obtaining the β-phase dipole orientation data of the piezoelectric thin film to be polarized; then, in cooperation with the thickness data set of the piezoelectric thin film to be polarized and the β-phase content data set of the piezoelectric thin film to be polarized, adjust the voltage value of each array unit of the first corona electrode array in real time and perform a polarization operation on the piezoelectric thin film to be polarized, obtaining the piezoelectric thin film after primary polarization;

[0091] The S3 includes the following steps:

[0092] S31. Adjust the rotational speeds of the unwinding roller, the first polarization roller, the second polarization roller, and the winding roller according to the tension of the piezoelectric film to be polarized attached to the first polarization roller and the second polarization roller until the piezoelectric film to be polarized is tightly attached to the first polarization roller and the second polarization roller;

[0093] S32. Use a WXRD device to measure the β-phase dipole orientation data in the transverse direction of the piezoelectric film to be polarized, and obtain the β-phase dipole orientation data of the piezoelectric film to be polarized; in combination with the thickness data set of the piezoelectric film to be polarized, the β-phase content data set of the piezoelectric film to be polarized, and the β-phase dipole orientation data of the piezoelectric film to be polarized, adjust the voltage value of each array unit (needle electrode) of the first corona electrode array in real time. After the adjustment is completed, perform a polarization operation on the piezoelectric film to be polarized to obtain a once-polarized piezoelectric film;

[0094] In S32, adjusting the voltage value of each array unit (needle electrode) of the first corona electrode array in real time in combination with the thickness data set of the piezoelectric film to be polarized, the β-phase content data set of the piezoelectric film to be polarized, and the β-phase dipole orientation data of the piezoelectric film to be polarized includes the following steps:

[0095] S321. Collect the average thickness data, average β-phase content data, β-phase dipole orientation data, and corresponding applied voltage data of the piezoelectric film during the polarization process of the piezoelectric film under standard conditions in multiple groups in history, and obtain the historical piezoelectric film thickness data set a1 = {a 11 ,..., a 1i ,..., a 1a′}, the historical piezoelectric film β-phase content data set a2 = {a 21 ,..., a 2i ,..., a 2a′}, the historical piezoelectric film β-phase dipole orientation data set

[0096] a3 = {a 31 ,..., a 3i ,..., a 3a′} and the first historical applied voltage data set

[0097] a4 = {a 41 ,..., a 4i ,..., a 4a′}, a 1i , a 2i , a 3i , a 4irespectively represent the average thickness data, average β-phase content data, β-phase dipole orientation data of the piezoelectric thin film during the polarization process of the i-th group of standard cases in history, and the corresponding applied voltage data, and a′ represents the total number of groups of data during the polarization process of the piezoelectric thin film under standard conditions in history;

[0098] S322. Construct a first applied voltage mapping model using the historical piezoelectric thin film thickness data set, historical piezoelectric thin film β-phase content data set, historical piezoelectric thin film β-phase dipole orientation data set, and the first historical applied voltage data set;

[0099] The S322 includes the following steps:

[0100] S3221. Construct a mapping equation between the piezoelectric thin film thickness data, piezoelectric thin film β-phase content data, piezoelectric thin film β-phase dipole orientation data, and applied voltage data to obtain an initial applied voltage mapping equation; as follows,

[0101]

[0102] Where, is the dependent variable of the initial applied voltage mapping equation, representing the applied voltage data of the array unit; are all independent variables of the initial applied voltage mapping equation, respectively representing the piezoelectric thin film thickness data, piezoelectric thin film β-phase content data, and piezoelectric thin film β-phase dipole orientation data; are respectively the corresponding independent variable coefficients; are respectively the corresponding independent variable exponential coefficients; α is the bias parameter of the initial applied voltage mapping equation;

[0103] S3222. Substitute the historical piezoelectric thin film thickness data set, historical piezoelectric thin film β-phase content data set, and historical piezoelectric thin film β-phase dipole orientation data set into the initial applied voltage mapping equation for mapping to obtain a historical initial applied voltage mapping data set represents the i-th initial applied voltage mapping data obtained by mapping;

[0104] S3223. Set an applied voltage mapping error threshold; calculate the error data between the historical initial applied voltage mapping data set and the first historical applied voltage data set to obtain historical applied voltage initial mapping error data b; the calculation formula is as follows,

[0105]

[0106] When the initial mapping error data of the historical applied voltage is greater than or equal to the applied voltage mapping error threshold, adjust the initial applied voltage mapping equation until the historical applied voltage initial mapping error data is less than the applied voltage mapping error threshold and the historical applied voltage initial mapping error data is greater than or equal to the applied voltage mapping error threshold, and then obtain the final applied voltage mapping equation; otherwise, there is no need to adjust the initial applied voltage mapping equation, and use the initial applied voltage mapping equation as the final applied voltage mapping equation;

[0107] The adjustment of the initial applied voltage mapping equation in S3223 includes the following steps:

[0108] S32231. Set the value ranges of the coefficients of each independent variable, the coefficients of the exponents of the independent variables, and the bias parameters in the initial applied voltage mapping equation to obtain the set of value ranges of the coefficients of the independent variables Set of value ranges of the coefficients of the exponents of the independent variables And the value range of the bias parameter respectively represent the lower limit and the upper limit of the value range of the bias parameter of the initial applied voltage mapping equation; They are as follows respectively,

[0109]

[0110] Among them, respectively represent the lower limits of the values of the 1st, 2nd, and 3rd coefficients of the independent variables in the initial applied voltage mapping equation; respectively represent the upper limits of the values of the 1st, 2nd, and 3rd coefficients of the independent variables in the initial applied voltage mapping equation; respectively represent the lower limits of the values of the 1st, 2nd, and 3rd coefficients of the exponents of the independent variables in the initial applied voltage mapping equation; respectively represent the upper limits of the values of the 1st, 2nd, and 3rd coefficients of the exponents of the independent variables in the initial applied voltage mapping equation;

[0111] Construct an applied voltage mapping adjustment Tianying population; set the maximum number of iterations of the applied voltage mapping adjustment Tianying population as b1' and the current number of iterations as b2', which are respectively denoted as the maximum number of voltage mapping iterations and the current number of voltage mapping iterations; the search space dimension of the applied voltage mapping adjustment Tianying population is 7 - dimensional;

[0112] S32232. Generate the initial positions of each Tianying in the applied voltage mapping adjustment Tianying population according to the set of value ranges of the coefficients of the independent variables, the set of value ranges of the coefficients of the exponents of the independent variables, and the value range of the bias parameter, to obtain the set of initial position matrices The generation formula is as follows,

[0113]

[0114] In the formula: respectively represent the position components of the initial position of the i-th eagle in the applied voltage mapping adjusted eagle population on the coefficients of the first, second, and third independent variables, the coefficients of the first, second, and third independent variable exponential coefficients, and the bias parameter dimension in the initial applied voltage mapping equation; rand i11 and rand i12 and rand i13 and rand i21 and rand i22 and rand i23 and rand i3 respectively represent random numbers generated for between 0 and 1;

[0115] S32233. Construct the fitness function c of the applied voltage mapping adjusted eagle population as follows:

[0116]

[0117] In the formula: c′ represents the error data between the dataset obtained by substituting a set of independent variable coefficients, independent variable exponential coefficients, and bias parameters obtained in each iteration into the initial applied voltage mapping equation, and then substituting the historical piezoelectric film thickness dataset, historical piezoelectric film β-phase content dataset, and historical piezoelectric film β-phase dipole orientation dataset in S3222 into the initial applied voltage mapping equation for mapping and the first historical applied voltage dataset;

[0118] S32234. Start the iteration. Before the iteration, set the current iteration number of the voltage mapping to 1. In the first round of iteration, use the fitness function c of the applied voltage mapping adjusted eagle population to calculate the fitness value of the initial position matrix of each eagle in the initial position matrix set, and obtain the first fitness value set; regard the maximum fitness value in the first fitness value set and the corresponding initial position of the eagle as the first global best fitness and the first global best position respectively; update the initial position matrix of each eagle in the initial position matrix set according to the first global best fitness and the first global best position; after the update is completed, add 1 to the current iteration number of the voltage mapping and perform the next round of iteration;

[0119] In each other iteration process, the fitness function c of the adjusted Tianying population is calculated using the applied voltage mapping. The fitness values of the position matrices of each Tianying in the adjusted Tianying population updated in the previous iteration process are obtained, resulting in a second set of fitness values. The maximum fitness value in the second set of fitness values and the corresponding Tianying position are respectively used as the second global best fitness and the second global best position. Each Tianying position matrix in the adjusted Tianying population updated in the previous iteration process is updated according to the second global best fitness and the second global best position. After the update is completed, the current iteration number of the voltage mapping is incremented by 1 and the next iteration is performed.

[0120] S32235. When b2'≥b1', stop the iteration to obtain the final global best fitness and the final global best position; otherwise, continue the iteration until b2'≥b1'. Use the final global best fitness as the historical optimized initial mapping error data of the applied voltage. When the historical optimized initial mapping error data of the applied voltage is less than the applied voltage mapping error threshold, the adjustment is completed to obtain the final applied voltage mapping equation; otherwise, return to S32234 to continue the iteration until the historical optimized initial mapping error data of the applied voltage is less than the applied voltage mapping error threshold.

[0121] S323. Cooperate with the first applied voltage mapping model to adjust the voltage value of each array unit (needle electrode) of the first corona electrode array in real time to obtain the first array unit voltage data set.

[0122] The S323 includes the following steps:

[0123] S3231. Cooperate with the thickness data set of the piezoelectric thin film to be polarized and the β-phase content data set of the piezoelectric thin film to be polarized to obtain and calculate the average thickness data and the average β-phase content data of the piezoelectric thin film region to be polarized corresponding to each array unit of the first corona electrode array, resulting in the first thickness data set of the piezoelectric thin film region to be polarized and the first β-phase content data set of the piezoelectric thin film region to be polarized.

[0124] S3232. Input each data in the first thickness data set of the piezoelectric thin film region to be polarized, the first β-phase content data set of the piezoelectric thin film region to be polarized, and the β-phase dipole orientation data of the piezoelectric thin film to be polarized into the final applied voltage mapping equation for mapping to obtain the first array unit voltage data set.

[0125] S324. Cooperate with the first array unit voltage data set to perform a primary polarization operation on the piezoelectric thin film to be polarized on the first polarization roller using the first corona electrode array. After the primary polarization operation is completed, the piezoelectric thin film after the primary polarization is obtained.

[0126] S4. Collect the piezoelectric performance data of multiple data acquisition points on the piezoelectric film after the first polarization, adjust the voltage value of each array unit of the second corona electrode array, and perform a second polarization on the piezoelectric film after the first polarization to obtain the piezoelectric film after the second polarization;

[0127] (7) The voltage closed-loop control module adjusts the voltage values of each unit of the second corona electrode array according to the data transmitted back by the second measurement module through algorithm calculation and correction to compensate for and correct the results of the first polarization. The specific adjustment method is as follows: If the piezoelectric properties of the film polarized by the first polarization roller are uniform and consistent everywhere, the voltage parameters of the second corona electrode array are the same as those of the first corona electrode array; if the piezoelectric properties of the film polarized by the first polarization roller are not consistent everywhere, the voltage of the electrode unit at the low-performance position in the second corona electrode array is increased, and the voltage of the electrode unit at the high-performance position is decreased;

[0128] (8) The piezoelectric film is continuously detected, moved, and polarized on the roller. The detection and control module continuously receives the monitoring data and, after algorithm calculation and correction, continuously controls and adjusts the voltage of each individual unit of the first and second corona electrode arrays;

[0129] The said S4 includes the following steps:

[0130] S41. Cooperate with the piezoelectric film data acquisition point set to collect the piezoelectric performance data of each data acquisition point on the piezoelectric film after the first polarization (including piezoelectric strain constant: reflecting the strain generated by a unit electric field or the electric displacement generated by a unit stress, directly characterizing the electromechanical coupling strength; piezoelectric stress constant: describing the linear relationship between stress and electric field, used to calculate the output voltage response; dielectric constant matrix: characterizing the polarization ability of the material under the action of an electric field, affecting the capacitance characteristics and energy storage efficiency; dielectric loss: measuring the degree of energy loss under the action of an electric field, affecting the high-frequency application performance; stiffness matrix: describing the stress-strain relationship of the material, etc., determining the mechanical response characteristics; compliance matrix: the inverse matrix of the stiffness matrix, used for the indirect calculation of strain and stress), and obtain the piezoelectric performance data set after the first polarization;

[0131] S42. Set the piezoelectric performance uniformity threshold after the first polarization; calculate the variance data of the piezoelectric performance data set after the first polarization to obtain the piezoelectric performance variance data after the first polarization; when the piezoelectric performance variance data after the first polarization is greater than or equal to the piezoelectric performance uniformity threshold after the first polarization, respectively use each voltage data in the first array unit voltage data set as the voltage data of each array unit in the second corona electrode array; otherwise, adjust the voltage data of each array unit in the second corona electrode array and perform a second polarization on the piezoelectric film after the first polarization to obtain the piezoelectric film after the second polarization;

[0132] Adjusting the voltage data of each array unit in the second corona electrode array in S42 includes the following steps:

[0133] S421. Collect piezoelectric performance data of the piezoelectric film and corresponding applied voltage data before polarizing the piezoelectric film under standard conditions in a number of historical cases, to obtain a historical piezoelectric performance data set and a historical second applied voltage data set;

[0134] S422. Construct an initial SVM model and set a training data ratio; divide the historical piezoelectric performance data set and the historical second applied voltage data set according to the training data ratio to obtain a historical piezoelectric performance training data set, a historical second applied voltage training data set, a historical piezoelectric performance test data set, and a historical second applied voltage test data set;

[0135] Then set a training error threshold; input the historical piezoelectric performance training data set as training data and the historical second applied voltage training data set as training labels into the initial SVM model for training; during the training process, when the training error is less than the training error threshold, stop training to obtain a trained SVM model; otherwise, continue training until the training error is less than the training error threshold;

[0136] Set a test accuracy threshold; input the historical piezoelectric performance test data set as test data and the historical second applied voltage test data set as test labels into the trained SVM model for testing; after testing, obtain test accuracy data; when the test accuracy data is greater than or equal to the test accuracy threshold, use the trained SVM model as a performance-related applied voltage mapping model; otherwise, continue training the trained SVM model until the test accuracy data is greater than or equal to the test accuracy threshold;

[0137] S423. Input the data in the piezoelectric performance data set after primary polarization into the performance-related applied voltage mapping model for mapping to obtain a second array unit voltage data set; adjust the voltage value of each array unit (needle electrode) of the second corona electrode array in coordination with the second array unit voltage data set;

[0138] S43. Set a repetition times threshold; repeat S1, S2, S3, S41, and S42 for the piezoelectric film after secondary polarization in coordination with the repetition times threshold.

[0139] Among them, an integrated laser thickness gauge (front end) and a WXRD (rear end) are integrated to form a multi-dimensional real-time monitoring network, and a feedback control module is combined to realize the dynamic compensation of polarization parameters; the first corona electrode array and the second corona electrode array adopt laterally movable needle electrodes, and the spacing can be automatically adjusted according to the film thickness; the polarization voltage of each needle electrode can be independently controlled; the first corona electrode array and the second corona electrode array adopt a modular quick-release structure, which supports replacement or cleaning, and each module is built-in with arc detection and power-off protection functions; the tip of the needle electrode is at a certain arc surface level coaxial with the polarization roller; the speeds of the unwinding roller, the polarization roller, and the winding roller are regulated by a servo motor, so that the film closely adheres to the zero-potential polarization roller while continuously passing through the electric field below the corona electrode array; the first polarization roller and the second polarization roller are made of a metal composite material, which has both high electrical conductivity, high voltage resistance, and fast heat conduction characteristics, and at the same time serves as a zero-potential electrode and a heating carrier.

[0140] Embodiment 2

[0141] Please refer to Figure 3 , this embodiment discloses a dynamic polarization system for preparing highly consistent piezoelectric films. The system can implement the method of the above embodiment, including a temperature acquisition module for the piezoelectric film to be polarized, a polarization temperature adjustment module for the piezoelectric film, a first data acquisition module for the piezoelectric film to be polarized, a voltage boosting module for the corona electrode array, a second data acquisition module for the piezoelectric film to be polarized, a unit voltage adjustment module for the first corona electrode array, a piezoelectric property data acquisition module, and a unit voltage adjustment module for the second corona electrode array;

[0142] The temperature acquisition module for the piezoelectric film to be polarized acquires the temperature data of the piezoelectric film to be polarized on the first polarization roller and the second polarization roller, and obtains the first polarization temperature data and the second polarization temperature data;

[0143] The polarization temperature adjustment module for the piezoelectric film adjusts the first polarization temperature data and the second polarization temperature data in cooperation with the standard polarization temperature;

[0144] The first data acquisition module for the piezoelectric film to be polarized measures the thickness data and the β-phase crystal content data at each data acquisition point on the piezoelectric film to be polarized, and obtains the dataset of the thickness of the piezoelectric film to be polarized and the dataset of the β-phase crystal content of the piezoelectric film to be polarized;

[0145] The voltage boosting module for the corona electrode array boosts the voltages of the first corona electrode array and the second corona electrode array in cooperation with the standard polarization voltage;

[0146] The second data acquisition module for the piezoelectric film to be polarized measures the β-phase crystal dipole orientation data of the piezoelectric film to be polarized, and obtains the β-phase crystal dipole orientation data of the piezoelectric film to be polarized;

[0147] The voltage adjustment module of the first corona electrode array unit adjusts the voltage value of each array unit of the first corona electrode array in real time in cooperation with the dipole orientation data of the β-phase of the piezoelectric film to be polarized, the data set of the thickness of the piezoelectric film to be polarized, and the data set of the β-phase content of the piezoelectric film to be polarized, and polarizes the piezoelectric film to be polarized to obtain a piezoelectric film after primary polarization;

[0148] The piezoelectric property data acquisition module acquires the piezoelectric property data of multiple data acquisition points on the piezoelectric film after primary polarization to obtain a data set of piezoelectric properties after primary polarization;

[0149] The voltage adjustment module of the second corona electrode array unit adjusts the voltage value of each array unit of the second corona electrode array in cooperation with the data set of piezoelectric properties after primary polarization and performs secondary polarization on the piezoelectric film after primary polarization to obtain a piezoelectric film after secondary polarization.

[0150] Embodiment III

[0151] A dynamic polarization device for preparing a piezoelectric film with high consistency, on which a program is stored, and when the program is executed by a processor, it is used to implement the above-mentioned dynamic polarization method for preparing a piezoelectric film with high consistency.

[0152] In the description of this specification, the description with reference to terms such as "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0153] The preferred embodiments of the invention disclosed above are only used to help explain the invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to the specific embodiments described. Obviously, many modifications and changes can be made according to the content of this specification. These embodiments are selected and specifically described in this specification to better explain the principle and practical application of the invention, so that those skilled in the art in the relevant technical field can understand and utilize the invention well.

Claims

1. A dynamic polarization method for preparing piezoelectric thin films with high consistency, characterized in that, It includes the following steps: S1. Collect the temperature data of the piezoelectric film to be polarized on the first polarization roller and the second polarization roller, and adjust it in combination with the standard polarization temperature to obtain the first polarization temperature data and the second polarization temperature data; S2. Measure the thickness data and β-phase content data at each data acquisition point on the piezoelectric film to be polarized to obtain the thickness data set of the piezoelectric film to be polarized and the β-phase content data set of the piezoelectric film to be polarized; Perform a boosting operation on the first corona electrode array and the second corona electrode array; S3. Measure the β-phase dipole orientation data of the piezoelectric film to be polarized to obtain the β-phase dipole orientation data of the piezoelectric film to be polarized; Then, in combination with the thickness data set of the piezoelectric film to be polarized and the β-phase content data set of the piezoelectric film to be polarized, adjust the voltage value of each array unit of the first corona electrode array in real time and perform a polarization operation on the piezoelectric film to be polarized to obtain a piezoelectric film after primary polarization; S4. Collect the piezoelectric performance data of multiple data acquisition points on the piezoelectric film after primary polarization, adjust the voltage value of each array unit of the second corona electrode array, and perform a secondary polarization on the piezoelectric film after primary polarization to obtain a piezoelectric film after secondary polarization.

2. The dynamic polarization method for preparing a highly consistent piezoelectric thin film according to claim 1, wherein The S1 includes the following steps: S11. Set the unwind roller, winding roller, first polarization roller, second polarization roller, and the piezoelectric film to be polarized; Use a temperature sensor to collect the temperature data of the piezoelectric film to be polarized on the first polarization roller and the second polarization roller; S12. Set the standard polarization temperature; When the temperature data of the piezoelectric film to be polarized on the first polarization roller and the second polarization roller is less than the standard polarization temperature, perform a heating operation on the piezoelectric film to be polarized until the temperature data of the piezoelectric film to be polarized on the first polarization roller and the second polarization roller collected in S11 is greater than or equal to the standard polarization temperature, and obtain the first polarization temperature data and the second polarization temperature data.

3. The dynamic polarization method for preparing a highly consistent piezoelectric thin film according to claim 2, characterized in that, The S2 includes the following steps: S21. Set several data acquisition points on the piezoelectric film to be polarized to obtain a piezoelectric film data acquisition point set; In combination with the piezoelectric film data acquisition point set, use a laser thickness gauge to measure the thickness data at each data acquisition point on the piezoelectric film to be polarized to obtain the thickness data set of the piezoelectric film to be polarized; Measure the β-phase content data at each data acquisition point on the piezoelectric film to be polarized to obtain the β-phase content data set of the piezoelectric film to be polarized; S22. Set the first corona electrode array, the second corona electrode array, and the standard polarization voltage; Perform a boosting operation on the first corona electrode array and the second corona electrode array until the voltages of the first corona electrode array and the second corona electrode array reach the standard polarization voltage.

4. A dynamic polarization method for preparing a highly consistent piezoelectric thin film according to claim 3, characterized in that, The S3 includes the following steps: S31. Adjust the rotation speeds of the unwind roller, first polarization roller, second polarization roller, and winding roller according to the tension of the piezoelectric film to be polarized attached to the first polarization roller and the second polarization roller until the piezoelectric film to be polarized is tightly attached to the first polarization roller and the second polarization roller; S32. Measure the β-phase dipole orientation data in the transverse direction of the piezoelectric thin film to be polarized, and obtain the β-phase dipole orientation data of the piezoelectric thin film to be polarized; in combination with the thickness data set of the piezoelectric thin film to be polarized, the β-phase content data set of the piezoelectric thin film to be polarized, and the β-phase dipole orientation data of the piezoelectric thin film to be polarized, adjust the voltage value of each array unit of the first corona electrode array in real time. After the adjustment is completed, perform a polarization operation on the piezoelectric thin film to be polarized to obtain a once-polarized piezoelectric thin film.

5. A dynamic polarization method for preparing a highly consistent piezoelectric thin film according to claim 4, characterized in that, In S32, the real-time adjustment of the voltage value of each array unit of the first corona electrode array in combination with the thickness data set of the piezoelectric thin film to be polarized, the β-phase content data set of the piezoelectric thin film to be polarized, and the β-phase dipole orientation data of the piezoelectric thin film to be polarized includes the following steps: S321. Collect the average thickness data, average β-phase content data, β-phase dipole orientation data, and corresponding applied voltage data of the piezoelectric thin film during the polarization process of the piezoelectric thin film under standard conditions in multiple groups in history, and obtain the historical piezoelectric thin film thickness data set, historical piezoelectric thin film β-phase content data set, historical piezoelectric thin film β-phase dipole orientation data set, and the first historical applied voltage data set. S322. Use the historical piezoelectric thin film thickness data set, historical piezoelectric thin film β-phase content data set, historical piezoelectric thin film β-phase dipole orientation data set, and the first historical applied voltage data set to construct a first applied voltage mapping model. S323. In combination with the first applied voltage mapping model, adjust the voltage value of each array unit of the first corona electrode array in real time to obtain the first array unit voltage data set. S324. Use the first corona electrode array in combination with the first array unit voltage data set to perform a primary polarization operation on the piezoelectric thin film to be polarized on the first polarization roller; after the primary polarization operation is completed, obtain a once-polarized piezoelectric thin film.

6. A dynamic polarization method for preparing a highly consistent piezoelectric thin film according to claim 5, characterized in that, The S322 includes the following steps: S3221. Construct a mapping equation between the piezoelectric thin film thickness data, piezoelectric thin film β-phase content data, piezoelectric thin film β-phase dipole orientation data, and applied voltage data to obtain an initial applied voltage mapping equation. S3222. Substitute the historical piezoelectric thin film thickness data set, historical piezoelectric thin film β-phase content data set, and historical piezoelectric thin film β-phase dipole orientation data set into the initial applied voltage mapping equation for mapping to obtain a historical initial applied voltage mapping data set. S3223. Set an applied voltage mapping error threshold; calculate the error data between the historical initial applied voltage mapping data set and the first historical applied voltage data set to obtain historical applied voltage initial mapping error data. When the historical applied voltage initial mapping error data is greater than or equal to the applied voltage mapping error threshold, adjust the initial applied voltage mapping equation until the historical applied voltage initial mapping error data is less than the applied voltage mapping error threshold or until the historical applied voltage initial mapping error data is greater than or equal to the applied voltage mapping error threshold, and obtain the final applied voltage mapping equation; otherwise, there is no need to adjust the initial applied voltage mapping equation, and use the initial applied voltage mapping equation as the final applied voltage mapping equation.

7. A dynamic polarization method for preparing a highly consistent piezoelectric thin film according to claim 6, characterized in that, The adjustment of the initial applied voltage mapping equation in S3223 includes the following steps: S32231. Set the value ranges of the coefficients of each independent variable, the coefficients of the exponents of the independent variables, and the bias parameters in the initial applied voltage mapping equation to obtain the set of value ranges of the coefficients of the independent variables, the set of value ranges of the coefficients of the exponents of the independent variables, and the value range of the bias parameters; construct the applied voltage mapping adjustment Tianying population; set the maximum number of iterations of the applied voltage mapping adjustment Tianying population as b′1 and the current number of iterations as b′2, which are respectively denoted as the maximum number of voltage mapping iterations and the current number of voltage mapping iterations; S32232. Generate the initial positions of each Tianying in the applied voltage mapping adjustment Tianying population according to the set of value ranges of the coefficients of the independent variables, the set of value ranges of the coefficients of the exponents of the independent variables, and the value range of the bias parameters, and obtain the set of initial position matrices; S32233. Construct the fitness function of the applied voltage mapping adjustment Tianying population; S32234. Start the iteration. Set the current number of voltage mapping iterations to 1 before the iteration; in each round of iteration, calculate the fitness values of the position matrices of each Tianying in the updated applied voltage mapping adjustment Tianying population in the previous round of iteration using the fitness function of the applied voltage mapping adjustment Tianying population and update the position matrices of each Tianying in the updated applied voltage mapping adjustment Tianying population in the previous round of iteration; after the update is completed, increment the current number of voltage mapping iterations by 1 and perform the next round of iteration; S32235. When b′2≥b′1, stop the iteration to obtain the final global best fitness and the final global best position; otherwise, continue the iteration until b′2≥b′1; use the final global best fitness as the historical optimized applied voltage initial mapping error data; when the historical optimized applied voltage initial mapping error data is less than the applied voltage mapping error threshold, the adjustment is completed to obtain the final applied voltage mapping equation; otherwise, return to S32234 to continue the iteration until the historical optimized applied voltage initial mapping error data is less than the applied voltage mapping error threshold.

8. A dynamic polarization method for preparing a highly consistent piezoelectric thin film according to claim 7, characterized in that, The S4 includes the following steps: S41. Cooperate with the piezoelectric film data acquisition point set to collect the piezoelectric performance data at each data acquisition point on the piezoelectric film after the first polarization to obtain the piezoelectric performance data set after the first polarization; S42. Set the uniformity threshold of piezoelectric properties after the first polarization; calculate the variance data of the piezoelectric property data set after the first polarization to obtain the piezoelectric property variance data after the first polarization; when the piezoelectric property variance data after the first polarization is greater than or equal to the uniformity threshold of piezoelectric properties after the first polarization, respectively use each voltage data in the first array unit voltage data set as the voltage data of each array unit in the second corona electrode array; otherwise, adjust the voltage data of each array unit in the second corona electrode array and perform a second polarization on the piezoelectric film after the first polarization to obtain a piezoelectric film after the second polarization. S43. Set the threshold of the number of repetitions; cooperate with the threshold of the number of repetitions to repeat S1, S2, S3, S41 and S42 for the piezoelectric film after the second polarization.

9. A system for implementing a dynamic polarization method for preparing a piezoelectric film with high uniformity as described in any one of claims 1-9.

10. A dynamic polarization device for preparing a piezoelectric film with high uniformity, on which a program is stored, and when the program is executed by a processor, it is used to implement the above-mentioned dynamic polarization method for preparing a piezoelectric film with high uniformity.

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