A piezoelectric composite material intelligent polarization system and method

Abstract

A piezoelectric composite intelligent polarization device, characterized by comprising a polarization device and a detection device. The polarization device comprises a base unit, a cover unit, and a pressure block, wherein the base unit comprises a printed circuit board, a conductive rubber strip, and a conductive rubber strip fixing structure; the cover unit comprises a cover plate, a spiral fine-tuning unit, a vacuum pumping unit, a resistive heating film, and a thin-film temperature sensor; and the detection device comprises a microprocessor, a signal amplification unit, a thyristor switching unit, a high-voltage amplification unit, an acquisition card slot, and a digital display. This invention has a simple structure and high assembly precision, and is suitable for polarizing piezoelectric composite materials of various sizes. It also performs intelligent detection of the assembly and polarization of piezoelectric composite materials, making the polarization process more intelligent and digital.

Description

Technical Field

[0001] The present invention relates to the field of piezoelectric composite material preparation, and in particular to an intelligent polarization system and method for piezoelectric composite materials under ultra-high voltage. Background Art

[0002] As a typical piezoelectric material, piezoelectric ceramics can sense external stress fields through the piezoelectric effect. In addition, the inverse piezoelectric effect allows the material to be used as an actuator. Since it generates large deformation and driving force under an external electric field, and is easy to control with electrical control signals, it is one of the most widely used smart materials. However, with the further expansion of the application scope of smart materials and the complexity of the application environment, due to the characteristics of traditional piezoelectric ceramic materials such as high brittleness, high impedance, and narrow bandwidth, it has poor compatibility with the main material and is prone to damage and fracture at the interface, which limits its use scenarios. Piezoelectric composite materials are multi-phase composite materials with piezoelectric effect formed by compounding piezoelectric phase materials (such as piezoelectric ceramics) with non-piezoelectric material phases (such as polymers) in a certain connectivity method. They have excellent piezoelectric properties, good flexibility, and strong designability, and can make up for the shortcomings of the above-mentioned traditional piezoelectric ceramic materials. Compared with the polarization of traditional piezoelectric ceramics, piezoelectric composite materials have a multi-segment slender structure, and the original polarization technology and solutions can no longer meet the polarization needs of piezoelectric composite materials. Piezoelectric constant d 33 It is one of the important characteristic parameters of piezoelectric materials. It is the proportional constant of the piezoelectric medium converting mechanical energy (or electrical energy) into electrical energy (or mechanical energy). It reflects the connection between stress or strain and electric field or electric displacement, and directly reflects the coupling relationship of the electromechanical properties of the material and the strength of the piezoelectric effect.

[0003] Patent publication number CN107026232A discloses a piezoelectric fiber polarization device and method, including a polarization device, a polarization cell, and a control unit. The device is suitable for direct polarization of slender piezoelectric fibers, but not for polarization of piezoelectric composite materials. The fibers must be placed in a polarization cell and an insulating liquid such as silicone oil must be added for polarization. Patent publication number CN102610741A discloses a piezoelectric material polarization device and method, including a polarization host, a polarization oil tank, and a polarization fixture for clamping the polarized specimen. This device and method are only suitable for polarizing general piezoelectric materials, but not for polarizing 1-3 thin-film piezoelectric composite materials. The specific design of the fixture is not disclosed. Summary of the Invention

[0004] A piezoelectric composite intelligent polarization device, characterized by comprising a polarization device and a detection device; wherein the polarization device comprises a base plate unit, a cover plate unit, and a pressure block; the base plate unit comprises a printed circuit board, a conductive rubber strip, and a conductive rubber strip fixing structure; the cover plate unit comprises a cover plate, a spiral fine-tuning unit, a vacuum pumping unit, a resistive heating film, and a thin film temperature sensor; and the detection device comprises a microprocessor, a signal amplification unit, a thyristor switching unit, a high-voltage amplification unit, an acquisition card slot, and a digital display screen.

[0005] Preferably, in the above-mentioned piezoelectric composite intelligent polarization device, four slide grooves are opened on the printed circuit board, and corresponding screw holes are provided on the conductive rubber strip fixing groove, which is positioned and fixed by tightening screws; the conductive rubber strip is placed in the conductive rubber sleeve fixing groove; and a scale is marked on one side of the slide groove to make the positioning of the conductive rubber strip fixing groove more accurate.

[0006] Preferably, in the above-mentioned piezoelectric composite intelligent polarization device, the front side of the printed circuit board is plated with interdigital electrodes, which are divided into two areas by the central axis of the printed circuit board, and the interdigital electrodes are arranged symmetrically. All positive electrodes in area A1 are led to one side of the printed circuit board, marked with a "+" pole, and all negative electrodes in area A2 are led to one side of the printed circuit board, marked with a "-" pole, to form the connection terminals of the printed circuit board.

[0007] Preferably, in the above-mentioned piezoelectric composite intelligent polarization device, the spiral fine-tuning unit is bonded to the front of the cover plate, the four positioning pin holes of the cover plate are copper-plated around, and the four positioning pin holes of the printed circuit board are also copper-plated around. The thin film temperature sensor and the resistive heating film are connected to the temperature measuring electrode and the heating electrode of the printed circuit board through the copper-plated area electrodes around the four positioning pins on the cover plate and the copper spring.

[0008] Preferably, in the above-mentioned piezoelectric composite intelligent polarization device, the conductive rubber strip is formed by alternately stacking conductive rubber and insulating rubber of equal size and then vulcanizing. The conductive particles in the conductive rubber are selected from graphite particles with a particle size of 5000 mesh or above. The thickness of a single layer of conductive rubber in the stacking direction should meet the following requirements: 1. The ratio of the polarization voltage to the thickness of the single layer of conductive rubber in the stacking direction is not greater than 20; 2. The surface width of the piezoelectric composite intermediate electrode in the polarization direction is the same as the thickness of the single layer of conductive rubber in the stacking direction; 3. The ratio of the width of the single interdigital electrode on the upper surface of the printed circuit board in the polarization direction to the thickness of the single layer of conductive rubber in the stacking direction is not less than 3 and is an integer multiple.

[0009] Preferably, in the above-mentioned piezoelectric composite material intelligent polarization device, the cover plate is a shell structure, made of acrylic plate, with several air holes on the front and a valve on the side, and the vacuum pumping unit is connected to the valve; a thin film temperature sensor is pasted on the front of the cover plate, and a resistive heating film is pasted on the film temperature sensor; several air holes are left on the resistive heating film and are connected to the air holes of the cover plate.

[0010] Preferably, in the above-mentioned piezoelectric composite intelligent polarization device, the thin film temperature sensor in the detection device is arranged on the cover plate, the signal amplification unit and the high-voltage amplification unit are respectively connected to the thyristor switching unit, and the thyristor switching unit and the thin film temperature sensor are connected to the microprocessor.

[0011] Preferably, in the above-mentioned piezoelectric composite material intelligent polarization device, the piezoelectric composite material polarization method of the piezoelectric composite material intelligent polarization device includes the following steps.

[0012] 1) Assembly: Measure the size of the piezoelectric composite material, symmetrically adjust the conductive rubber strip fixing groove to keep it consistent with the width of the piezoelectric composite material, and then install it parallel to the printed circuit board through bolts, and place the conductive rubber strip in the conductive rubber strip fixing groove; cut a mask of appropriate size, paste it on the front of the cover, block the pores that exceed the size range of the piezoelectric material, paste the thin film temperature sensor on the front of the cover, paste the resistive heating film on the thin film temperature sensor, and place the piezoelectric composite material on the cover to contact the resistive heating film; adjust the spiral fine-tuning unit to pre-tighten the piezoelectric composite material, connect the vacuum exhaust unit to the valve of the cover and start exhausting to make it a negative pressure state, adjust the spiral fine-tuning unit again for fine-tuning, connect the cover and the base plate through a threaded positioning pin and a copper spring, and the positioning pin is covered with a copper spring. Place the pressure block on the cover and press it tightly, adjust the spiral fine-tuning unit for fine-tuning to make it in close contact with the side of the piezoelectric composite material.

[0013] 2) Check the negative electrode connection: insert the negative detection finger electrode array of the printed circuit board into the acquisition card slot; start the detection device, control the thyristor switching unit to disconnect the positive and negative electrodes from the high-voltage amplifier, and connect the thyristor switching unit to the detection circuit. The detection circuit first detects whether the positive and negative electrodes of the printed circuit board are in a normal open circuit state. If they are open circuit, the detection circuit self-checks the connection between the piezoelectric composite material in the polarization device and the negative electrode part of the interdigital electrode of the printed circuit board. The microprocessor controls the IO port to output a high level to the negative electrode of the interdigital electrode, and then calculates the level of the negative electrode connection N1 in the piezoelectric composite material based on the feedback from the negative detection finger electrode array to the microprocessor IO port.

[0014] 3) Check the positive electrode connection: Start the detection circuit in the detection device. The detection circuit first detects whether the positive and negative electrodes of the printed circuit board are in a normal open circuit state. If they are open circuit, the detection circuit performs a self-check on the connection between the piezoelectric composite material in the polarization device and the positive electrode part of the interdigital electrode of the printed circuit board. The microprocessor in the controller controls the IO port to output a high level to the positive electrode of the interdigital electrode. The level of the positive electrode detection finger electrode array is fed back to the IO port of the microprocessor to calculate the number N2 of positive electrode connections in the piezoelectric composite material.

[0015] 4) Determine the connection status: If the microprocessor in the controller calculates |N1 - N2| ≤ 1, the piezoelectric composite material structure is intact and properly connected to the polarization device. Otherwise, it indicates that there may be defects in the piezoelectric composite material structure or the piezoelectric composite material and the polarization device are not fully connected, and some electrodes are in a suspended state, requiring reassembly.

[0016] 5) Polarization risk test: After confirming that the piezoelectric composite material is connected to the polarization device normally, the detection device starts the polarization mode, controls the thyristor switching unit to disconnect from the detection circuit, and connects the positive and negative electrodes of the piezoelectric composite material to the positive and negative electrodes of the high-voltage amplifier respectively; the microprocessor controls the polarization voltage output IO to output a quasi-polarization voltage V0, which is amplified n times by the high-voltage amplifier to form a polarization voltage NV0, where the value of NV0 is related to the length of the piezoelectric composite material. According to the length L (mm) of the piezoelectric composite material, the quasi-polarization voltage NV0 is determined to be 2.812*X (KV). The microprocessor controls the IO port to output a polarization high voltage with an amplitude of 120%*NV0 at a period of 100HZ within 3S to detect whether there is a breakdown risk.

[0017] 6) Normal polarization: If it works normally, it enters the first polarization stage. The detection device monitors the temperature through closed-loop control based on the thin film temperature sensor, controls the resistive heating film to raise the temperature to the polarization temperature, and polarizes the piezoelectric composite with the preset polarization voltage NV0 for 8 minutes.

[0018] 7) Polarization is completed; BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to better describe the present invention, a brief description is given with reference to the following drawings.

[0020] Figure 1 It is a structural schematic diagram of the piezoelectric composite material intelligent polarization device of the present invention.

[0021] Figure 2 This is a schematic structural diagram of the cover plate of the piezoelectric composite intelligent polarization device of the present invention.

[0022] Figure 3Schematic diagram a of the structure of the cover unit of the piezoelectric composite material intelligent polarization device of the present invention.

[0023] Figure 4 Schematic diagram b of the structure of the cover unit of the piezoelectric composite material intelligent polarization device of the present invention.

[0024] Figure 5 FIG. 3 is a structural schematic diagram c of the cover unit of the piezoelectric composite material intelligent polarization device of the present invention.

[0025] Figure 6 Schematic diagram d of the structure of the cover unit of the piezoelectric composite material intelligent polarization device of the present invention.

[0026] Figure 7 Schematic diagram a of the structure of the bottom plate unit of the piezoelectric composite material intelligent polarization device of the present invention.

[0027] Figure 8 Schematic diagram b of the structure of the bottom plate unit of the piezoelectric composite material intelligent polarization device of the present invention.

[0028] Figure 9 FIG. 3 is a structural schematic diagram c of the bottom plate unit of the piezoelectric composite material intelligent polarization device of the present invention. FIG.

[0029] Figure 10 This is a schematic structural diagram of the conductive rubber strip of the piezoelectric composite material intelligent polarization device of the present invention.

[0030] Figure 11 This is a detection schematic diagram of the piezoelectric composite intelligent polarization device of the present invention.

[0031] In the figure, 1-polarization device, 2-vacuum pumping unit, 3-detection device, 11-cover unit, 12-base unit, 13-pressing block, 301-acquisition card slot a, 302-acquisition card slot b, 303-acquisition device host, 304-wiring harness, 305-acquisition card slot c, 306-detection device host switch, 307-digital display, 1101-cover positioning pin hole, 1102-screw fine-tuning unit, 1103-cover, 1104-air hole, 1105-valve, 1106-resistive heating film, 1107-thin film temperature sensor, 1108-piezoelectric composite material, 1109-temperature measuring electrode a, 1110-temperature measuring electrode b, 1111-heating electrode a, 1112-heating electrode b, 1113-soldering point, 1114-mask, 1201-positioning pin, 1202-conductive rubber strip fixing groove a, 1203-fastening bolt, 1204-printed circuit board slide groove a, 1219-temperature measuring electrode a1, 1205-printed circuit board, 1206-conductive rubber strip a, 1207-conductive rubber strip fixing groove b, 1220-heating electrode Pole a1, 1208 - polarization voltage negative input terminal, 1209 - polarization voltage positive input terminal, 1221 - heating electrode b1, 1210 - conductive rubber strip b, 1222 - temperature measuring electrode b1, 1223 - copper spring, 1211 - printed circuit board slide b, 1212 - printed circuit board slide c, 1213 - printed circuit board a slide d, 1214 - positive detection electrode array, 1215 - negative detection electrode array, 1216 - positive finger electrode array, 1217 - negative finger electrode array, 1218 - fastening nut, 1224 - temperature measuring electrode a1 terminal, 1225 - temperature measuring electrode b1 terminal, 1226 - slide scale, 1227 - conductive rubber layer in the conductive rubber strip, 1228 - insulating rubber layer in the conductive rubber strip; DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention more clear and explicit compared to the prior art, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by relevant technical personnel in this field without making creative work should fall within the scope of protection of the present invention.

[0033] The piezoelectric composite intelligent polarization device of the present invention includes a polarization device 1 and a detection device 3, wherein the polarization device includes a cover unit 11, a base unit 12, and a pressure block 13. The detection device 3 consists of a detection device host 303 and an acquisition card slot a301, an acquisition card slot b302, and an acquisition card slot c305. The detection device host and the card slots are connected by a multi-core shielded cable. The base unit 12 includes a printed circuit board 1205, a conductive rubber strip a1206, a conductive rubber strip b1210, a conductive rubber strip fixing groove a1202, a conductive rubber strip fixing groove b1207, a positioning pin 1201, and a copper spring 1223; the cover unit 11 includes a cover 1103, a spiral micro-motion structure 1102, a positioning pin hole 1101, a thin film temperature sensor 1107, a resistive heating film 1106, an air hole 1104, and a valve 1105.

[0034] The cover plate 1103 is bonded to the spiral fine-tuning unit 1106 for fine-tuning. Four locating pin holes 1101 are provided on the cover plate, which is connected to the printed circuit board 1205 via locating pins 1201 and copper springs 1223. A mask 1114 is bonded to the front of the cover plate. The piezoelectric composite material to be polarized 1108 is bonded to the resistive heating film 1106 and clamped by the eight spiral fine-tuning units 1106. The resistive heating film 1106 is connected to the heating electrodes 1111 and 1112, and electrically connected to the heating electrodes 1220 and 1221, respectively, via copper springs 1223. The film temperature sensor 1107 is connected to the temperature measuring electrodes 1109 and 1110, and electrically connected to the temperature measuring electrodes 1219 and 1222, respectively, via copper springs 1223.

[0035] The front of the bottom plate 12 unit is divided into two areas by the central axis of the printed circuit board, and the interdigital electrodes are symmetrically arranged. The left and right electrodes are parallel to each other and staggered. All 1216-positive finger-type electrode arrays in area A1 are led to one side of the printed circuit board, marked with a "+" pole, forming a 1209-polarization voltage positive input terminal, and all remaining negative electrodes form a 1215-negative detection electrode array, which is connected to the acquisition card slot a 301. All 1217-negative finger-type electrode arrays in area A2 are led to one side of the printed circuit board, marked with a "-" pole, forming a 1208-polarization voltage negative input terminal, and all remaining positive electrodes form a 1214-positive detection electrode array, which is connected to the acquisition card slot c 305 are connected, and four oblong grooves are opened on both sides of the printed circuit board. The oblong grooves of the printed circuit board are connected by bolts 1203 and fastening nuts 1218 to fix the conductive rubber strip fixing groove a1202 and the conductive rubber strip fixing groove b1207. The conductive rubber strip a1206 and the conductive rubber strip b1210 are installed in the conductive rubber strip fixing groove.

[0036] The piezoelectric composite material polarization method of the present invention includes the following steps.

[0037] 1) Assembly: Measure the size of the piezoelectric composite material 1108, symmetrically adjust the conductive rubber strip fixing groove a 1202 and the conductive rubber strip fixing groove b 1207 to keep them consistent with the width of the piezoelectric composite material 1108, and then install them parallel to the printed circuit board 1205 using bolts 1203. Place the conductive rubber strip a 1206 and the conductive rubber strip b 1210 in the conductive rubber strip fixing groove a 1202 and the conductive rubber strip fixing groove b respectively. 1207; cut a mask 1114 of appropriate size and paste it on the front of the cover 1103 to block the pores 1104 that exceed the size range of the piezoelectric material, paste the thin film temperature sensor 1107 on the cover 1103, paste the resistive heating film 1106 on the thin film temperature sensor 1107, place the piezoelectric composite material 1108 on the resistive heating film 1106, and contact the resistive heating film 1106; adjust the spiral fine-tuning unit to fix the piezoelectric composite material, connect the vacuum exhaust unit 2 to the valve of the cover 1103 and start exhausting to make it a negative pressure state, adjust the spiral fine-tuning unit 1102 again for fine-tuning, connect the cover 11 and the base 12 through the positioning pin 1201 and the copper spring 1223, place the pressing block 13 on the cover 11 and press it tightly, adjust the spiral fine-tuning unit 1102 for fine-tuning to make it in close contact with the side of the piezoelectric composite material 1108.

[0038] 2) Check the negative electrode connection: insert the negative electrode detection finger-type electrode array 1215 of the printed circuit board into the acquisition card slot a301, and insert the negative terminal of the polarization voltage 1208 into the acquisition card slot b302; start the detection circuit in the detection device 3, control the thyristor switching unit to disconnect the positive and negative electrodes from the high-voltage amplifier, and connect the thyristor switching unit to the detection circuit. The detection circuit first detects whether the positive and negative electrodes of the printed circuit board are in a normal open circuit state. If they are open circuit, the detection circuit performs a self-check on the connection between the piezoelectric composite material in the polarization device and the negative electrode part 1217 of the interdigital electrode of the printed circuit board. The microprocessor in the detection device controls the IO port to output a high level to the negative electrode of the interdigital electrode, and then calculates the number N1 of negative electrodes connected in the piezoelectric composite material based on the level fed back to the IO port of the microprocessor through the negative electrode detection array.

[0039] 3) Check the positive electrode connection: insert the positive detection finger electrode array 1214 of the printed circuit board into the acquisition card slot c305, and insert the polarization voltage positive input terminal 1209 into the acquisition card slot b302; start the detection circuit in the detection device 3, the detection circuit first detects whether the positive and negative electrodes of the printed circuit board are in a normal open circuit state. If they are open circuit, the detection circuit performs a self-check on the connection between the piezoelectric composite material 1108 in the polarization device and the positive finger electrode 1216 of the interdigital electrode of the printed circuit board 1205. The microprocessor in the detection device controls the IO port to output a high level to the polarization voltage positive input terminal 1209 of the interdigital electrode, and then calculates the number N2 of positive electrodes connected in the piezoelectric composite material based on the level fed back to the microprocessor IO port through the positive detection electrode array 1214.

[0040] 4) Determine the connection status: If the microprocessor in the controller calculates |N1 - N2| ≤ 1, it indicates that the piezoelectric composite material structure is intact and is properly connected to the polarization device. Otherwise, it indicates that there may be defects in the structure of the piezoelectric composite material 1118 or the piezoelectric composite material 1108 is not fully connected to the polarization device 1, and some electrodes are in a suspended state, requiring reassembly.

[0041] 5) Polarization risk test: After confirming that the piezoelectric composite material 1118 is connected to the polarization device 1 normally, the detection device 3 starts the polarization mode, and the controller controls the thyristor switching unit to disconnect from the detection circuit, and connects the positive and negative electrodes of the piezoelectric composite material to the positive and negative electrodes of the high-voltage amplifier respectively; the microprocessor controls the polarization voltage output IO to output a quasi-polarization voltage V0, which is amplified n times by the high-voltage amplifier to form a polarization voltage NV0, where the value of NV0 is related to the length of the piezoelectric composite material. According to the length L (mm) of the piezoelectric composite material, the quasi-polarization voltage NV0 is determined to be 2.812*X (KV), and the microprocessor controls the IO port to output a polarization high voltage with an amplitude of 120%*NV0 at a period of 100HZ within 3S to detect whether there is a breakdown risk.

[0042] 6) Normal polarization: If it works normally, it enters the first stage of polarization. The detection device 3 is based on the resistive heating film 1106 and is connected to the 1111-heating electrode a and the 1112-heating electrode, and is connected to the 1220-heating electrode a1 and the 1221-heating electrode b1 through the copper spring 1223. The 1208 polarization voltage negative input terminal and the 1209-polarization voltage positive input terminal are inserted into the acquisition card slot b 302. Through closed-loop control, the resistive heating plate is controlled to increase the temperature to the polarization temperature, and the piezoelectric composite is polarized for 8 minutes with the preset polarization voltage NV0; the thin film thermistor 1107 is connected to the 1109-temperature measuring electrode a and the 1110-temperature measuring electrode b, and is connected to the 1219-temperature measuring electrode a1 and the 1222-temperature measuring electrode b1 through the copper spring 1223. The 1224-temperature measuring electrode a1 terminal and the 1225-temperature measuring electrode b1 terminal are inserted into the acquisition card slot b. In 302, polarization temperature monitoring is implemented. Through closed-loop control, the resistive heating film 1106 is controlled to increase its temperature to the polarization temperature, and the piezoelectric composite is polarized for 8 minutes at a preset polarization voltage NV0.

[0043] 7) Polarization is completed.

[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them. Although the present invention has been described in detail with reference to the aforementioned embodiments, relevant technical personnel in the field should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalent or similar ones, without causing the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A piezoelectric composite material polarization method, using a piezoelectric composite material intelligent polarization system, characterized in that: The steps include: 1) Assembly: Measure the size of the piezoelectric composite material, symmetrically adjust the conductive rubber strip fixing groove to keep it consistent with the width of the piezoelectric composite material, and then install it parallel to the printed circuit board with bolts, and place the conductive rubber strip in the conductive rubber strip fixing groove; cut a suitable mask and stick it on the front of the cover to block the pores that exceed the size range of the piezoelectric material, stick the thin film temperature sensor to the cover, stick the resistive heating film to the thin film temperature sensor, and place the piezoelectric composite material on the cover so that it contacts the resistive heating film; adjust the spiral fine-tuning structure to pre-tighten the piezoelectric composite material, connect the vacuum pumping device to the valve of the cover and start pumping air to make it a negative pressure state, adjust the spiral fine-tuning structure again for fine-tuning, connect the cover and the base plate with a threaded positioning pin and a copper spring, and the positioning pin is covered with a copper spring. Place the pressure block on the cover and press it tightly, and adjust the spiral fine-tuning structure for fine-tuning so that it is in close contact with the side of the piezoelectric composite material; 2) Check the negative electrode connection: Insert the negative detection finger electrode array on the printed circuit board into the detection card slot; The detection device is started, and the thyristor switching unit is controlled to disconnect the positive and negative electrodes from the high-voltage amplifier. The thyristor switching unit is connected to the detection circuit. The detection circuit first detects whether the positive and negative electrodes of the printed circuit board are in a normal open circuit state. If they are open circuit, the detection circuit performs a self-check on the connection between the piezoelectric composite material in the polarization device and the negative electrode portion of the interdigital electrode of the printed circuit board. The microprocessor in the controller controls the IO port to output a high level to the negative electrode of the interdigital electrode. The level of the negative electrode detection finger electrode array is fed back to the IO port of the microprocessor to calculate the number N1 of negative electrodes connected in the piezoelectric composite material. 3) Check the positive electrode connection: Start the detection circuit in the controller. The detection circuit first detects whether the positive and negative electrodes of the printed circuit board are in a normal open circuit state. If they are open circuit, the detection circuit performs a self-check on the connection between the piezoelectric composite material in the polarization device and the positive electrode part of the interdigital electrode of the printed circuit board. The microprocessor in the controller controls the IO port to output a high level to the positive electrode of the interdigital electrode. The positive electrode detection finger electrode array then feeds back the level to the IO port of the microprocessor to calculate the number N2 of positive electrode connections in the piezoelectric composite material. 4) Confirm the connection status: If the microprocessor in the controller calculates |N1 - N2| ≤ 1, the piezoelectric composite material structure is intact and properly connected to the polarization device. Otherwise, it means that there may be defects in the piezoelectric composite material structure or the piezoelectric composite material and the polarization device are not fully connected, and some electrodes are in a suspended state, requiring reassembly. 5) Polarization risk test: After confirming that the piezoelectric composite material is properly connected to the polarization device, the detection device activates the polarization mode, controls the thyristor switching unit to disconnect from the detection circuit, and connects the positive and negative electrodes of the piezoelectric composite material to the positive and negative electrodes of the high-voltage amplifier respectively. The microprocessor controls the polarization voltage output IO to output a quasi-polarization voltage V0, which is amplified n times by the high-voltage amplifier to form a polarization voltage NV0. The value of NV0 is related to the length of the piezoelectric composite material. Based on the length L (mm) of the piezoelectric composite material, the quasi-polarization voltage NV0 is determined to be 2.812*X (KV). The microprocessor controls the IO port to output a polarization high voltage with an amplitude of 120%*NV0 at a period of 100 Hz within 3 seconds to detect whether there is a breakdown risk. 6) Normal polarization: If it works normally, it enters the first polarization stage. The detection device monitors the temperature through closed-loop control based on the thin film temperature sensor, controls the resistive heating film to raise the temperature to the polarization temperature, and polarizes the piezoelectric composite at the preset polarization voltage NV0 for 8 minutes. 7) Polarization is completed.

2. A piezoelectric composite material polarization method according to claim 1, characterized in that: The piezoelectric composite intelligent polarization system includes a polarization device and a detection device; wherein the polarization device includes a base plate unit, a cover plate unit, and a pressure block; the base plate unit includes a printed circuit board, a conductive rubber strip, and a conductive rubber strip fixing groove; the cover plate unit includes a cover plate, a spiral fine-tuning unit, a vacuum pumping unit, a resistive heating film, and a thin film temperature sensor; the detection device includes a microprocessor, a signal amplification unit, a high-voltage amplification unit, a thyristor switching unit, an acquisition card slot, and a digital display screen.

3. A piezoelectric composite material polarization method according to claim 2, characterized in that: The printed circuit board is provided with four slide grooves, one side of which is marked with scales. The conductive rubber strip fixing groove is provided with corresponding screw holes, which are positioned and fixed by tightening screws; the conductive rubber strip is placed in the conductive rubber strip fixing groove.

4. A piezoelectric composite material polarization method according to claim 2, characterized in that: The front of the printed circuit board is plated with interdigitated electrodes, which are symmetrically arranged in two areas along the central axis of the printed circuit board. All positive electrodes in area A1 are connected to a side of the printed circuit board marked with a "+" pole, and all negative electrodes in area A2 are connected to a side of the printed circuit board marked with a "-" pole, forming the connection terminals of the printed circuit board. The spacing between the fixing slots of the conductive rubber strip can be adjusted on the slide slot using a set screw.

5. A piezoelectric composite material polarization method according to claim 2, characterized in that: The spiral fine-tuning unit is bonded to the front of the cover plate, and the four positioning pin holes of the cover plate are copper-plated. The four positioning pin holes of the printed circuit board are also copper-plated. The thin film temperature sensor and the resistive heating film are connected to the temperature measuring electrode and the heating electrode of the printed circuit board through the copper-plated area electrodes around the four positioning pins on the cover plate and the copper spring.

6. A piezoelectric composite material polarization method according to claim 2, characterized in that: The conductive rubber strip is formed by alternately stacking conductive rubber and insulating rubber of equal size and then vulcanizing. The conductive particles in the conductive rubber are selected Graphite particles with a particle size of 5000 mesh or above are selected; the thickness of the single-layer conductive rubber in the stacking direction should meet the following requirements: ① the ratio of the polarization voltage to the thickness of the single-layer conductive rubber in the stacking direction is not greater than 20; ② the surface width of the intermediate electrode of the piezoelectric composite material in the polarization direction is the same as the thickness of the single-layer conductive rubber in the stacking direction; ③ the ratio of the width of the single-finger electrode on the surface of the printed circuit board in the polarization direction to the thickness of the single-layer conductive rubber in the stacking direction is not less than 3 and is an integer multiple.

7. A piezoelectric composite material polarization method according to claim 2, characterized in that: The acquisition card slot is connected to the bottom plate detection array electrode when in the detection electrode connection state.

8. The method for polarizing a piezoelectric composite material according to claim 5, wherein: The cover plate is a shell structure made of acrylic plate, with several air holes on the front and a valve on the side, and the vacuum pumping unit is connected to the valve; a mask is pasted on the cover plate to block the air holes that exceed the size range of the piezoelectric material, a thin film temperature sensor is pasted on the cover plate, and a resistive heating film is pasted on the thin film temperature sensor; several air holes are left on the resistive heating film and the thin film temperature sensor, which are connected to the air holes of the cover plate.

9. A piezoelectric composite material polarization method according to claim 6, characterized in that: The temperature sensing unit in the detection device, namely the thin film temperature sensor, is arranged on the cover plate. The signal amplifying unit and the high voltage amplifying unit are respectively connected to the thyristor switching unit. The thyristor switching unit and the thin film temperature sensor are connected to the microprocessor.

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