Flexible sensing device for use in strong electric and magnetic fields and method of manufacturing the same

Abstract

The application discloses a flexible sensing device used in a strong electric field and a strong magnetic field and a manufacturing method thereof, and the method comprises the following steps: selecting micro low-power components, including a PCB antenna, a wireless communication module, a master control chip, a battery, a flexible circuit board (FPCB), and configuring sensor components; performing PCB layout and welding on the components to obtain a first-stage FPCB; performing anti-interference structure design with a metasurface structure on the first-stage FPCB to obtain a second-stage FPCB; performing packaging processing on the second-stage FPCB to obtain the flexible sensing device used in the strong electric field and the strong magnetic field; and performing metasurface structure electromagnetic field shielding performance test and overall anti-interference performance test on the flexible sensing device through a test platform. The flexible sensing device has good flexibility and meets the scene application of the complex strong electric field and strong magnetic field environment in the power industry.

Description

Technical Field

[0001] This invention belongs to the field of power transmission facility sensing technology, and relates to a flexible sensing device and its manufacturing method for use under strong electric and magnetic fields. Background Technology

[0002] The power industry encompasses a wide variety of transmission and substation facilities, each with distinct structures. For instance, transmission line tension clamps are typically cylindrical, though slight deformation may occur due to manufacturing processes. Similarly, composite insulators have cylindrical curved ends, while suspension disc or glass insulators have spherical curved ends. Substation facilities such as transformer terminals, instrument transformer connectors, and bushing terminals are all irregularly shaped curved structures, making it difficult for conventional sensing devices to fully adapt to these structures, severely impacting the accuracy of sensing measurements. Most power equipment, especially irregularly shaped equipment, still lacks effective sensing devices.

[0003] Flexible sensors are highly adaptable to irregularly shaped surfaces and can better accommodate complex surfaces and curved shapes, making them particularly advantageous for applications on irregularly shaped objects. However, most existing flexible sensing devices are used in general industrial or wearable applications. Due to the special nature of the power industry, the equipment to be sensed is mostly high-voltage equipment, and electric and magnetic fields can easily interfere with or even damage the sensing devices. Furthermore, power equipment comes in various voltage levels, with different structural sizes and electromagnetic field strengths. Even equipment of the same voltage level from different manufacturers has different structures, and the impact on the sensing device increases with the voltage level. Therefore, flexible sensing devices are not suitable for the high-voltage, strong magnetic field environments of the power industry because they are easily affected by electromagnetic fields. Moreover, existing electromagnetic protection methods use metal shielding materials to completely seal non-wireless communication units, while the wireless communication antenna is exposed outside the shielding material. Induced voltage can be introduced into the circuit board through the antenna, causing breakdown and damage to the circuit board and components, especially under high voltage environments of hundreds of thousands of volts. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a flexible sensing device and its manufacturing method for use under strong electric and magnetic fields, enabling effective sensing of power transmission and transformation equipment in the power industry.

[0005] The present invention adopts the following technical solution.

[0006] A first aspect of the present invention provides a method for manufacturing a flexible sensing device under strong electric and magnetic fields, comprising:

[0007] Miniature low-power components are selected, including PCB antennas, wireless communication modules, main control chips, batteries, and flexible printed circuit boards (FPCBs), and sensor devices are configured.

[0008] The components are laid out and soldered on a PCB to obtain the first-stage FPCB;

[0009] An anti-interference structure with metasurface structure is designed for the first-stage FPCB to obtain the second-stage FPCB. The process includes: after wrapping the first-stage FPCB with an insulating layer, placing the first-stage FPCB with the insulating layer in a mold, performing a first encapsulation with silicone material, then uniformly spraying a polyester coating on the surface of the silicone material, electroplating metallic nickel on the polyester coating, electroplating an iron layer on the metallic nickel, and electroplating nickel metal on the iron layer to obtain the second-stage FPCB; simultaneously, during the electroplating process, a laser-cut mask with a metasurface structure is fixed directly above the PCB antenna to manufacture the metasurface structure.

[0010] The second-stage FPCB is packaged and processed to obtain a flexible sensing device applicable to strong electric and magnetic field environments.

[0011] The electromagnetic field shielding performance and overall anti-interference performance of the flexible sensing device were tested using a testing platform.

[0012] The testing platform includes a strong magnetic field environment simulation device, a high-voltage electric field environment simulation device, a hollow square box, a set of radio frequency communication transceiver modules, a magnetic field measuring instrument, and an electric field measuring instrument. The square box is a hexahedron made of silicone material, and one side is detachable and configured as a metasurface structure. The set of radio frequency communication transceiver modules is matched with the transparent frequency band of the metasurface structure. The strong magnetic field environment simulation device uses a series circuit composed of a high current generator and wires to simulate a strong magnetic field environment. The high-voltage electric field environment simulation device simulates a high-voltage electric field environment through a series resonant AC withstand voltage test device.

[0013] Electromagnetic field shielding performance and overall anti-interference performance of the metasurface structure of the flexible sensing device were tested. Specifically, the tests included: electric field shielding performance of the metasurface structure based on electric field strength; magnetic field shielding performance of the metasurface structure based on magnetic field strength, communication signal strength and packet loss rate; and overall anti-interference performance based on communication signal strength and packet loss rate.

[0014] The calculation process for the communication signal strength is as follows:

[0015] (1) The receiver decomposes the received wireless signal into IQ signals including in-phase and quadrature components, and uses a filter to filter the IQ signals;

[0016] (2) Calculate the instantaneous power of each sampling point of the filtered IQ signal. Based on instantaneous power Calculate the average value of the power sequence and standard deviation ;

[0017] in ;

[0018] In the formula, For each n sampling point of the in-phase component in the IQ signal, For each n sampling point of the orthogonal component in the IQ signal;

[0019] (3) Based on the average value of the power sequence and standard deviation The instantaneous power is preprocessed using a Gaussian distribution to obtain the preprocessed power. :

[0020] ,

[0021] Where k is an adjustable parameter;

[0022] (4) Based on the power after preprocessing Calculate the communication signal strength:

[0023] ,

[0024] ,

[0025] ,

[0026] in, This represents the total power after filtration. Where is the average power, and N is the number of sampling points for the signal.

[0027] Preferably, the wireless communication module is a low-power Zigbee chip with a high frequency of 2.4 GHz; the main control chip is a chip with standby, sleep, and stop modes, and the current in sleep mode is ≤1μA; the battery is a button cell or a flexible irregular-shaped battery.

[0028] Preferably, the PCB layout of the components includes: the main control chip, battery and peripheral circuits, wireless communication module and sensor components are arranged on one side of the FPCB central axis, the PCB antenna is arranged on the other side of the FPCB central axis, and the PCB antenna is arranged at the edge of the FPCB.

[0029] Preferably, the encapsulation process for the second-stage FPCB includes: placing the second-stage FPCB in a mold using an injection molding process, and performing secondary encapsulation using silicone material.

[0030] Preferably, the process of testing the magnetic field shielding performance of the metasurface structure of the flexible sensing device by the testing platform includes:

[0031] (1) Directly contact the square box metasurface structure with the wires of the strong magnetic field environment simulation device, place the magnetic field measuring instrument inside the square box, and measure the magnetic field strength value B1 under the hexahedron without the metasurface structure and the magnetic field strength value B2 under the hexahedron with the metasurface structure. If If it is successful, proceed to (2); otherwise it is unqualified. Adjust the metasurface structure of the flexible sensing device and retest.

[0032] (2) The square box metasurface structure is directly contacted with the wires of the strong magnetic field environment simulation device. The transmitter of the radio frequency communication transceiver module is placed inside the square box, and the receiver is 50cm away from the square box. The communication signal strength RSSI1 and packet loss rate X1 of the receiver without the metasurface structure hexahedron are calculated based on the wireless signal received by the receiver. The communication signal strength RSSI2 and packet loss rate X2 of the receiver with the metasurface structure hexahedron are calculated. If RSSI2 > RSSI1, X2 < X1 and X2 ≤ 5%, the magnetic field shielding performance of the metasurface structure is qualified. Otherwise, it is unqualified. The metasurface structure of the flexible sensing device is adjusted and then retested.

[0033] Preferably, the process of the test platform testing the electric field shielding performance of the metasurface structure of the flexible sensing device is as follows:

[0034] The box-shaped metasurface structure is directly contacted with the wires of the high-voltage electric field environment simulation device. The electric field tester is placed inside the box, and the electric field strength value under the hexahedron without the metasurface structure is E1. The electric field strength value under the hexahedron with the metasurface structure is E2. If E2 < E1 and E2 < 1kV / m, the electric field shielding performance of the metasurface structure is qualified. Otherwise, it is unqualified. The metasurface structure of the flexible sensing device is adjusted and the test is repeated.

[0035] Preferably, the test platform performs overall anti-interference performance testing on the flexible sensing device, including testing the overall magnetic field and electric field shielding performance of the flexible sensing device.

[0036] The overall magnetic field shielding performance test of the flexible sensing device includes:

[0037] The flexible sensing device is directly contacted with the wires of the strong magnetic field environment simulation device. The receiving end of the radio frequency communication transceiver module is 50cm away from the flexible sensing device. The communication module of the flexible sensing device acts as the transmitting end and communicates with the receiving end of the radio frequency communication transceiver module. The communication signal strength and packet loss rate of the receiving end are calculated based on the wireless signal received by the receiving end. If the communication signal strength of the receiving end is greater than the preset corresponding threshold and the packet loss rate is less than the preset corresponding threshold, the overall magnetic field shielding performance of the flexible sensing device is qualified. Otherwise, it is unqualified, and the structure of the flexible sensing device is adjusted and retested.

[0038] The overall electric field shielding performance test of the flexible sensing device includes:

[0039] The flexible sensing device is directly connected to the wires of the high-voltage electric field environment simulation device. The receiving end of the radio frequency communication transceiver module is 50cm away from the flexible sensing device. The communication module of the flexible sensing device acts as the transmitting end and communicates with the receiving end of the radio frequency communication transceiver module. The communication signal strength and packet loss rate of the receiving end are calculated based on the wireless signal received by the receiving end. If the communication signal strength of the receiving end is greater than the preset corresponding threshold and the packet loss rate is less than the preset corresponding threshold, the overall electric field shielding performance of the flexible sensing device is qualified. Otherwise, it is unqualified, and the structure of the flexible sensing device is adjusted and retested.

[0040] A second aspect of the present invention provides a flexible sensing device for use under strong electric and magnetic fields, comprising a PCB antenna, a wireless communication module, a main control chip, a battery, a flexible printed circuit board (FPCB), a sensor, an anti-interference structure, and a packaging structure; wherein the PCB antenna, the wireless communication module, the main control chip, the battery, and the sensor are arranged and soldered on the FPCB; an anti-interference structure with a metasurface structure is provided outside the FPCB, and a packaging structure is provided outside the anti-interference structure.

[0041] Compared with the prior art, the beneficial effects of the present invention include at least the following:

[0042] The flexible sensing device of this invention employs anti-interference and encapsulation design, possessing properties such as waterproofing, temperature resistance, insulation, corona prevention, electromagnetic field shielding, and wireless communication signal transparency. It is suitable for application scenarios in the complex and strong electric and magnetic field environments of the power industry. Based on the method of this invention, various flexible sensing devices that meet the application needs of the power industry can be prepared according to monitoring requirements.

[0043] In terms of anti-interference packaging and processing, for the manufacturing of flexible sensing devices in strong electric and magnetic field environments, the method of electroplating a metal protective layer on silicone avoids the problems of incomplete wrapping of flexible anti-interference materials and the impact of metasurface structure and PCB antenna position deviation on shielding and communication performance, thereby improving the overall anti-interference performance of flexible sensing devices.

[0044] For testing the shielding performance of strong electric and magnetic fields, conventional methods mainly involve conducting wireless communication tests in anechoic chambers. This differs from the actual scenario of strong electric and magnetic fields in high-voltage power lines, neglecting the influence of external power frequency electric and magnetic fields. Furthermore, existing anechoic chamber laboratories cannot directly simulate the strong electric and magnetic fields of high-voltage power lines. Therefore, to ensure the flexible sensing device can function effectively in practical applications, this invention proposes a targeted testing platform and method. Moreover, addressing the issue of large measurement errors in conventional wireless communication quality testing methods, this invention employs a combination of the baseband IQ power integration method and the Gaussian distribution preprocessing method to improve the accuracy of wireless communication measurements.

[0045] The flexible sensing device designed and manufactured in this invention is used for electromagnetic field shielding performance testing and overall anti-interference performance testing of metasurface structure. A corresponding testing platform is proposed, and the device is evaluated based on indicators such as magnetic field strength, communication signal strength, and packet loss rate. The communication signal strength is calculated by combining the baseband IQ power integration method and the Gaussian distribution preprocessing method. This method improves the accuracy of power measurement by preprocessing the received signal and utilizing the characteristics of Gaussian distribution, which can improve the accuracy of wireless communication signal strength calculation and reduce the influence of strong electric and magnetic fields generated by high voltage and high current in the conductor.

[0046] The flexible sensing device of the present invention is made of small, flexible components with excellent flexibility, which can achieve close fit with irregular structural objects of power facilities to achieve accurate sensing. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of the PCB layout of the present invention;

[0048] Figure 2 This is a schematic diagram illustrating the anti-interference protection of the present invention;

[0049] The attached diagram is labeled as follows: 1-PCB antenna; 2-Wireless communication module; 3-Main control chip; 4-Battery and peripheral circuits; 5-FPCB; 6-FPCB board with components already soldered; 7-High temperature resistant acetate tape; 8-Flexible metamaterial;

[0050] Figure 3 It is a device for simulating strong magnetic field environments;

[0051] Figure 4 It is a high-voltage electric field environment simulation device. Detailed Implementation

[0052] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of this invention. The embodiments described in this application are merely some embodiments of this invention, and not all embodiments. Based on the spirit of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this invention.

[0053] Embodiment 1 of the present invention provides a method for manufacturing a flexible sensing device under strong electric and magnetic fields. The method mainly involves the design and manufacturing of the sensing device in terms of power consumption, PCB layout, anti-interference, and packaging. Specifically, it includes:

[0054] Step 1: Select miniature low-power components, including PCB antenna 1, wireless communication module 2, main control chip 3, battery, flexible circuit board FPCB 5, and configure sensor components;

[0055] More preferably, the low-power design scheme is as follows:

[0056] The selection principle for components is to prioritize miniaturization and low power consumption. For example, the wireless communication module should use a low-power Zigbee chip with a high frequency of 2.4GHz. The current of the main control chip in sleep mode should be ≤1μA, and it should have standby, sleep, and stop low-power mode functions. Battery selection: Option 1 is to choose a small button battery (16mm in diameter), and Option 2 is to choose a flexible irregularly shaped battery, which is easy to bend and deform.

[0057] The sensor should be selected from MEMS or flexible devices, and the specific configuration should be based on the actual monitoring needs.

[0058] Step 2: Perform PCB layout and soldering of components to obtain the first-stage FPCB;

[0059] More preferably, the PCB layout scheme is as follows:

[0060] When laying out the PCB, factors such as the fit with the structure during installation, the location of the wireless communication antenna, and shielding need to be considered. The PCB layout is as follows: Figure 1 As shown. PCB layout follows these principles:

[0061] When selecting components, choose those with the smallest possible size. The wiring connections for each component are completed according to the circuit design diagram during the fabrication of the FPCB5 (flexible printed circuit board). PCB antenna 1 should be placed near the edge of the FPCB5; this layout takes into account the protection of subsequent sensing devices. The main control chip 3, battery and peripheral circuits 4, and wireless communication module 2 are arranged on one side of the central axis of the FPCB5, and the sensor components should also be arranged on the left side as much as possible, with PCB antenna 1 placed on the other side.

[0062] Step 3: Design the anti-interference structure and manufacture the anti-interference material for the first-stage FPCB to obtain the second-stage FPCB;

[0063] More preferably, the anti-interference method and the anti-interference material manufacturing scheme are as follows:

[0064] Since the flexible sensing device is a wireless sensor without an external power cord, interference protection is achieved by adding a metal layer to the outside of the pre-soldered FPCB board 6 (first-stage FPCB board). This layer must not interfere with the wireless communication of the flexible sensing device. Furthermore, it must be non-flammable in case of abnormal device damage to prevent damage to electrical facilities. The interference protection process is as follows: Figure 2As shown, this invention addresses the need for flexible sensors in irregularly shaped structures. To ensure the sensor remains flexible after anti-interference protection, a metal protective layer is electroplated onto the flexible shell, and a metasurface structure is formed using a mask. Specifically: after the first-stage FPCB is wrapped with an insulating layer, a first encapsulation process is performed, including: using injection molding, placing the first-stage FPCB with the insulating layer in a mold, and performing the first encapsulation using silicone material; then, an electroplating process is used to electroplat a metal shielding layer with a metasurface structure onto the silicone surface, including: firstly, uniformly spraying a polyester coating onto the cleaned silicone surface to ensure coverage. The first-stage FPCB is covered to increase the adhesion of the silicone surface. Then, nickel is electroplated onto the polyester coating, followed by an iron layer with high conductivity and magnetic permeability. Finally, an anti-oxidation and anti-corrosion nickel metal is electroplated onto the iron layer to obtain the second-stage FPCB. During the electroplating process, a laser-cut mask with a metasurface structure is fixed directly above the PCB antenna to facilitate the electroplating process of the metal shielding layer and to create the metasurface structure. The insulating layer uses high-temperature resistant acetate tape 7, which has good insulation, high temperature resistance, solvent resistance, and anti-aging properties, and can withstand short-term high temperatures up to 180°C.

[0065] The metal shielding layer uses flexible metamaterial 8 as the anti-interference material. Specifically, it uses a metal layer with a metasurface structure directly electroplated on silicone as the anti-interference layer to achieve metal shielding. By designing the structure on the material, it can achieve wireless communication signal gain effect.

[0066] The structure of the flexible metamaterial 8 is attached to the PCB antenna 1 of the device. That is, the metasurface structure of the metal shielding layer is matched with the position of the PCB antenna. The metasurface structure is located directly above the PCB antenna so that wireless communication signals can be reliably transmitted through the metasurface.

[0067] Step 4: The second-stage FPCB is packaged and processed to obtain a flexible sensing device applicable to strong electric and magnetic field environments.

[0068] More preferably, the packaging and processing scheme is as follows:

[0069] The flexible sensing device is packaged with silicone material, with a hardness of 50 being ideal. Silicone material has the characteristics of being waterproof, temperature resistant, insulating, and anti-corona, which can meet the requirements of high-voltage and outdoor environments in the power industry.

[0070] The flexible sensing device is packaged using injection molding, whereby the entire flexible sensing device is placed in a mold and integrally formed with a silicone shell. This method produces a flexible sensing device with excellent sealing, effectively shielding it from strong external electromagnetic interference while ensuring reliable transmission of wireless communication signals.

[0071] Embodiment 2 of the present invention provides a flexible sensing device for use under strong electric and magnetic fields, including a PCB antenna 1, a wireless communication module 2, a main control chip 3, a battery, an FPCB 5, sensor components, an anti-interference structure, and a packaging structure;

[0072] Among them, the PCB antenna 1, wireless communication module 2, main control chip 3, battery and peripheral circuits 4, and sensor components are laid out and soldered on FPCB 5;

[0073] The FPCB5 has a silicon protective layer and an electroplated substrate layer. The electroplated substrate layer has an anti-interference structure with a metasurface structure, and the anti-interference structure has an encapsulation structure.

[0074] This invention relates to the testing of the anti-interference performance of metasurface structures and the testing of the overall anti-interference performance of flexible sensing devices.

[0075] The test platform consists of a strong magnetic field environment simulation device, a high voltage electric field environment simulation device, and a six-sided (one side is detachable) hollow box made of silicone material. The box is a hexahedron of silicone shell prepared using the same method as above. A metasurface structure is prepared to match the size of the box. The size of the detachable side is known and can be hung and removed.

[0076] Prepare another set of RF communication transceiver modules that match the transparent frequency band of the metasurface structure, a magnetic field measuring instrument, and an electric field measuring instrument.

[0077] The magnetic field measuring instrument and electric field measuring instrument store the magnetic field strength and electric field strength values, while the computer software records the received radio frequency signal strength. A high current generator is used to simulate a strong magnetic field environment, and a series resonant AC withstand voltage test device is used. Figure 4 The device shown simulates a high-voltage electric field environment.

[0078] Regarding the performance testing of metasurface structures:

[0079] 1. The process for testing the magnetic field shielding performance of metasurface structures is as follows:

[0080] (1) Integrating the metasurface structure of the square box with Figure 3 The wires of the strong magnetic field environment simulation device shown are in direct contact. The magnetic field measuring instrument is placed inside the box, and the magnetic field strength value is measured as B1 under the hexahedron without metasurface structure, and as B2 under the hexahedron with metasurface structure. If the condition is not met, proceed with (2); otherwise, if the condition is not met, adjust the metasurface structure of the flexible sensing device and retest.

[0081] (2) Integrating the metasurface structure of the square box with Figure 3The wires of the strong magnetic field environment simulation device are in direct contact. The radio frequency communication transmitter is placed inside the box (generally 2cm away from the metasurface structure surface), and the receiver is 50cm away from the box (this can be selected according to application needs). The communication signal strength of the receiver without the sixth face is calculated as RSSI1 and the packet loss rate is X1. The communication signal strength of the receiver with the hexahedron of the metasurface structure surface is calculated as RSSI2 and the packet loss rate is X2. When RSSI2 > RSSI1, X2 < X1 and X2 ≤ 5%, the magnetic field shielding performance of the metasurface structure is qualified. Otherwise, it is unqualified. The metasurface structure of the flexible sensing device is adjusted and retested.

[0082] The magnitude of the current and voltage applied to the conductor in the above test is determined according to the voltage level of the actual application (e.g., applying a current of 600A and a voltage of 220kV).

[0083] More preferably, to improve the accuracy of RSSI calculation for wireless communication signals and reduce the influence of strong magnetic fields generated by large currents in the conductors, the baseband IQ power integration method and the Gaussian distribution preprocessing method are combined to calculate RSSI. This method improves the accuracy of power measurement by preprocessing the received signal and utilizing the characteristics of the Gaussian distribution.

[0084] (1) First, a filter is used to decompose the IQ (wireless signal) into in-phase (I) and quadrature (Q) components at the receiving end, which is used to accurately describe the state of the signal.

[0085] Filter the IQ signal, for example, by using a low-pass filter to remove high-frequency noise (determined by the wireless communication frequency band of the sensing device).

[0086] (2) Calculate the instantaneous power at each sampling point:

[0087] ,

[0088] Calculate the mean and standard deviation of the power series:

[0089] ,

[0090] ,

[0091] (3) Gaussian distribution preprocessing:

[0092] By utilizing the Gaussian distribution, data with power values ​​greater than a certain threshold (usually the mean minus a certain multiple of the standard deviation) can be extracted, reducing erroneous measurements caused by noise.

[0093] ,

[0094] Here, k is an adjustable parameter, typically ranging from 1 to 3.

[0095] (4) Power calculation and RSSI calculation:

[0096] Calculate the total power after filtering:

[0097] ,

[0098] Calculate the average power:

[0099] ,

[0100] Convert to RSSI value (dBm):

[0101] ,

[0102] 2. The process for testing the electric field shielding performance of metasurface structures is as follows:

[0103] The metasurface structure of the square box and Figure 4 The wires of the high-voltage electric field environment simulation device are in direct contact. The electric field tester is placed inside the box (generally 2cm away from the metasurface structure surface). The electric field strength value under the hexahedron without the metasurface structure surface is E1, and the electric field strength value under the hexahedron with the metasurface structure surface is E2. If E2 < E1 and E2 < 1kV / m, the electric field shielding performance of the metasurface structure is qualified; otherwise, it is unqualified. The metasurface structure of the flexible sensing device is adjusted and the test is repeated.

[0104] Regarding the overall anti-interference performance testing of flexible sensing devices:

[0105] 1. The overall magnetic field shielding performance test of the flexible sensing device includes:

[0106] Flexible sensing devices and distance Figure 3 The wires of the strong magnetic field environment simulation device shown are directly connected. The receiving end of the radio frequency communication transceiver module is 50cm away from the flexible sensing device. The communication module of the flexible sensing device acts as the transmitting end and communicates with the receiving end of the radio frequency communication transceiver module. The communication signal strength and packet loss rate of the receiving end are calculated based on the wireless signal received by the receiving end. If the communication signal strength and packet loss rate of the receiving end are better than the preset corresponding threshold, the overall magnetic field shielding performance of the flexible sensing device is qualified. Otherwise, it is unqualified. The structure of the flexible sensing device is adjusted and the test is repeated.

[0107] 2. The overall electric field shielding performance test of the flexible sensing device includes:

[0108] Flexible sensing device and Figure 4The high-voltage electric field environment simulation device shown is in direct contact with the wires. The magnetic field shielding performance test method is repeated. First, the wireless signal emitted by the flexible sensing device should be received normally, indicating that the flexible sensing device is operating normally. Then, the communication signal strength and packet loss rate of the receiving end are calculated based on the wireless signal received by the receiving end. If the communication signal strength and packet loss rate of the receiving end are still better than the preset corresponding threshold, the overall electric field shielding performance test of the flexible sensing device is qualified. Otherwise, it is unqualified, and the structure of the flexible sensing device is adjusted and the test is repeated.

[0109] Compared with the prior art, the beneficial effects of the present invention include at least the following:

[0110] The flexible sensing device of this invention employs anti-interference and encapsulation design, possessing properties such as waterproofing, temperature resistance, insulation, corona prevention, electromagnetic field shielding, and wireless communication signal transparency. It is suitable for application scenarios in the complex and strong electric and magnetic field environments of the power industry. Based on the method of this invention, various flexible sensing devices that meet the application needs of the power industry can be prepared according to monitoring requirements.

[0111] In terms of anti-interference packaging and processing, for the manufacturing of flexible sensing devices in strong electric and magnetic field environments, the method of electroplating a metal shielding layer on silicone avoids the problems of incomplete wrapping of flexible anti-interference materials and the impact of metasurface structure and PCB antenna position deviation on shielding and communication performance, thereby improving the overall anti-interference performance of flexible sensing devices.

[0112] For testing the shielding performance of strong electric and magnetic fields, conventional methods mainly involve conducting wireless communication tests in anechoic chambers. This differs from the actual scenario of strong electric and magnetic fields in high-voltage power lines, neglecting the influence of external power frequency electric and magnetic fields. Furthermore, existing anechoic chamber laboratories cannot directly simulate the strong electric and magnetic fields of high-voltage power lines. Therefore, to ensure the flexible sensing device can function effectively in practical applications, this invention proposes a targeted testing platform and method. Moreover, addressing the issue of large measurement errors in conventional wireless communication quality testing methods, this invention employs a combination of the baseband IQ power integration method and the Gaussian distribution preprocessing method to improve the accuracy of wireless communication measurements.

[0113] The flexible sensing device designed and manufactured in this invention is used for electromagnetic field shielding performance testing and overall anti-interference performance testing of metasurface structure. A corresponding testing platform is proposed, and the device is evaluated based on indicators such as magnetic field strength, communication signal strength, and packet loss rate. The communication signal strength is calculated by combining the baseband IQ power integration method and the Gaussian distribution preprocessing method. This method improves the accuracy of power measurement by preprocessing the received signal and utilizing the characteristics of Gaussian distribution, which can improve the accuracy of wireless communication signal strength calculation and reduce the influence of strong electric and magnetic fields generated by high voltage and high current in the conductor.

[0114] The flexible sensing device of the present invention is made of small, flexible components with excellent flexibility, which can achieve close contact with irregular structural objects of power facilities to achieve accurate sensing.

[0115] This invention encapsulates the first-stage FPCB with an insulating layer, followed by a metal shielding layer with a metasurface structure. This addresses interference issues under high-voltage, strong magnetic field environments, effectively protecting the sensing device and providing electromagnetic shielding. The entire sensing device is enclosed within this metasurface structure metal shielding layer, which uses a flexible metasurface structure metal shielding material as its anti-interference material. This flexible material meets the flexibility requirements of flexible sensing devices. The metasurface structure prevents the wireless communication antenna from blocking electromagnetic signals within the shielding material, thus ensuring wireless communication signal transmission and stability. The flexible metasurface structure metal shielding material is manufactured by preparing the metasurface structure on a metal fabric, providing flexibility, anti-interference capabilities, and wireless signal transmission. The process employs screen printing and laser cutting, allowing for precise cutting of the metasurface structure on the metal fabric and ink printing of images. After laser cutting, the shape of the pattern can be inspected to determine the quality of the anti-interference material, facilitating quality control.

[0116] Based on the application scenario, this invention takes into account aspects such as waterproofing, temperature resistance, insulation, and corona prevention. Specifically, it uses silicone to encapsulate the sensing device as a whole, eliminating the need for connecting or pasting the outer shell, thus improving the reliability of the sensing device in outdoor high-voltage and strong magnetic field environments.

[0117] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the protection scope of the claims of the present invention.

Claims

1. A method for manufacturing a flexible sensing device under strong electric and magnetic fields, characterized in that, include: Miniature low-power components are selected, including PCB antennas, wireless communication modules, main control chips, batteries, flexible printed circuit boards (FPCBs), and sensor devices are configured. The components are laid out and soldered on a PCB to obtain the first-stage FPCB; The first-stage FPCB is designed and manufactured with an anti-interference structure featuring a metasurface structure to obtain the second-stage FPCB. The process includes: after wrapping the first-stage FPCB with an insulating layer, placing the first-stage FPCB with the insulating layer in a mold, performing a first encapsulation using silicone material, then uniformly spraying a polyester coating onto the surface of the silicone material, electroplating metallic nickel on the polyester coating, electroplating an iron layer on the metallic nickel, and electroplating nickel metal on the iron layer to obtain the second-stage FPCB; simultaneously, during the electroplating process, a laser-cut mask with a metasurface structure is fixed directly above the PCB antenna to create the metasurface structure. The second-stage FPCB is packaged and processed to obtain a flexible sensing device applicable to strong electric and magnetic field environments. The electromagnetic field shielding performance and overall anti-interference performance of the flexible sensing device were tested using a testing platform. The testing platform includes a strong magnetic field environment simulation device, a high-voltage electric field environment simulation device, a hollow square box, a set of radio frequency communication transceiver modules, a magnetic field measuring instrument, and an electric field measuring instrument. The square box is a hexahedron made of silicone material, and one side is detachable and configured as a metasurface structure. The set of radio frequency communication transceiver modules is matched with the transparent frequency band of the metasurface structure. The strong magnetic field environment simulation device uses a series circuit composed of a high current generator and wires to simulate a strong magnetic field environment. The high-voltage electric field environment simulation device simulates a high-voltage electric field environment through a series resonant AC withstand voltage test device. The electromagnetic field shielding performance test and overall anti-interference performance test of the metasurface structure for the flexible sensing device specifically include: electric field shielding performance test of the metasurface structure based on electric field strength, magnetic field shielding performance test of the metasurface structure based on magnetic field strength, communication signal strength and packet loss rate, and overall anti-interference performance test based on communication signal strength and packet loss rate. The calculation process for the communication signal strength is as follows: (1) The receiver decomposes the received wireless signal into IQ signals including in-phase and quadrature components, and uses a filter to filter the IQ signals; (2) Calculate the instantaneous power of each sampling point of the filtered IQ signal. Based on instantaneous power Calculate the average value of the power sequence and standard deviation ; in ; ； ； In the formula, For each n sampling point of the in-phase component in the IQ signal, For each n sampling point of the orthogonal component in the IQ signal; (3) Based on the average value of the power sequence and standard deviation The instantaneous power is preprocessed using a Gaussian distribution to obtain the preprocessed power. : ； Where k is an adjustable parameter; (4) Based on the power after preprocessing Calculate the communication signal strength: ； ； ； in, This represents the total power after filtration. Where is the average power, and N is the number of sampling points for the signal.

2. The manufacturing method of the flexible sensing device for strong electric and magnetic fields according to claim 1, characterized in that: The wireless communication module uses a low-power Zigbee chip with a high frequency of 2.4GHz; the main control chip has standby, sleep, and stop modes, and the current in sleep mode is ≤1μA; the battery is a button cell or a flexible irregular-shaped battery.

3. The method for manufacturing a flexible sensing device under strong electric and magnetic fields according to claim 1, characterized in that: The PCB layout of the components includes: the main control chip, battery and peripheral circuits, wireless communication module and sensor components are arranged on one side of the FPCB central axis, and the PCB antenna is arranged on the other side of the FPCB central axis and at the edge of the FPCB.

4. The method for manufacturing a flexible sensing device under strong electric and magnetic fields according to claim 1, characterized in that: The encapsulation process for the second-stage FPCB includes: using injection molding to place the second-stage FPCB in a mold and using silicone material for secondary encapsulation.

5. The method for manufacturing a flexible sensing device under strong electric and magnetic fields according to claim 1, characterized in that: The process of testing the magnetic field shielding performance of the metasurface structure of the flexible sensing device on the test platform includes: (1) Directly contact the square box metasurface structure with the wires of the strong magnetic field environment simulation device, place the magnetic field measuring instrument inside the square box, and measure the magnetic field strength value B1 under the hexahedron without the metasurface structure and the magnetic field strength value B2 under the hexahedron with the metasurface structure. If If it is successful, proceed to (2); otherwise, it is unqualified. Adjust the metasurface structure of the flexible sensing device and retest. (2) The square box metasurface structure is directly contacted with the wires of the strong magnetic field environment simulation device. The transmitter of the radio frequency communication transceiver module is placed inside the square box, and the receiver is 50cm away from the square box. The communication signal strength RSSI1 and packet loss rate X1 of the receiver without the metasurface structure hexahedron are calculated based on the wireless signal received by the receiver. The communication signal strength RSSI2 and packet loss rate X2 of the receiver with the metasurface structure hexahedron are calculated. If RSSI2 > RSSI1, X2 < X1 and X2 ≤ 5%, the magnetic field shielding performance of the metasurface structure is qualified. Otherwise, it is unqualified. The metasurface structure of the flexible sensing device is adjusted and then retested.

6. The method for manufacturing a flexible sensing device under strong electric and magnetic fields according to claim 1, characterized in that: The process of testing the metasurface structure electric field shielding performance of the flexible sensing device using the test platform is as follows: The box-shaped metasurface structure is directly contacted with the wires of the high-voltage electric field environment simulation device. The electric field tester is placed inside the box, and the electric field strength value under the hexahedron without the metasurface structure is E1. The electric field strength value under the hexahedron with the metasurface structure is E2. If E2 < E1 and E2 < 1kV / m, the electric field shielding performance of the metasurface structure is qualified. Otherwise, it is unqualified. The metasurface structure of the flexible sensing device is adjusted and the test is repeated.

7. The method for manufacturing a flexible sensing device under strong electric and magnetic fields according to claim 1, characterized in that: The test platform performs overall anti-interference performance tests on the flexible sensing device, including tests on the overall magnetic field and electric field shielding performance of the flexible sensing device. The overall magnetic field shielding performance test of the flexible sensing device includes: The flexible sensing device is placed in direct contact with a strong magnetic field environment simulation device. The receiving end of the radio frequency communication transceiver module is 50cm away from the flexible sensing device. The communication module of the flexible sensing device acts as the transmitting end and communicates with the receiving end of the radio frequency communication transceiver module. The communication signal strength and packet loss rate of the receiving end are calculated based on the wireless signal received by the receiving end. If the communication signal strength of the receiving end is greater than the preset corresponding threshold and the packet loss rate is less than the preset corresponding threshold, the overall magnetic field shielding performance of the flexible sensing device is qualified. Otherwise, it is unqualified, and the structure of the flexible sensing device is adjusted and retested. The overall electric field shielding performance test of the flexible sensing device includes: The flexible sensing device is directly connected to the wires of the high-voltage electric field environment simulation device. The receiving end of the radio frequency communication transceiver module is 50cm away from the flexible sensing device. The communication module of the flexible sensing device acts as the transmitting end and communicates with the receiving end of the radio frequency communication transceiver module. The communication signal strength and packet loss rate of the receiving end are calculated based on the wireless signal received by the receiving end. If the communication signal strength of the receiving end is greater than the preset corresponding threshold and the packet loss rate is less than the preset corresponding threshold, the overall electric field shielding performance of the flexible sensing device is qualified. Otherwise, it is unqualified, and the structure of the flexible sensing device is adjusted and retested.

8. A flexible sensing device for use under strong electric and magnetic fields, manufactured using the method described in any one of claims 1-7, characterized in that, It includes a PCB antenna, a wireless communication module, a main control chip, a battery, a flexible printed circuit board (FPCB), sensor components, an anti-interference structure, and a packaging structure; wherein, the PCB antenna, wireless communication module, main control chip, battery, and sensor components are laid out and soldered on the FPCB; an anti-interference structure with a metasurface structure is provided outside the FPCB, and a packaging structure is provided outside the anti-interference structure.

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