Partial discharge insulation defect integrated detection sensor

Abstract

The present invention provides an integrated sensor for detecting partial discharge insulation defects. The sensor comprises a flexible thin-film piezoelectric material, a first metal electrode structure and a second metal electrode structure disposed on either side of the flexible thin-film piezoelectric material, a first conductor connected to the first metal electrode structure, and a second conductor connected to the second metal electrode structure. The present invention utilizes a flexible thin-film piezoelectric material as a dielectric substrate, and forms a piezoelectric ultrasonic sensor and an ultra-high frequency sensor with the metal electrode structure disposed thereon. The output end of the metal electrode structure can simultaneously output both ultrasonic and ultra-high frequency signals. When detecting partial discharge insulation defects in electrical equipment, the sensor can be built into the inner wall of the metal casing of the equipment, performing differential analysis based on the difference in arrival time between the output ultrasonic signal and the ultra-high frequency signal, or the difference in their corresponding frequencies, to accurately locate the location of the partial discharge.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of partial discharge detection, and in particular to an integrated partial discharge insulation defect detection sensor. Background Art

[0002] As power grids continue to operate for longer periods of time, the safety and reliability requirements for power supply systems are becoming increasingly stringent. However, insulation defects are unavoidable during the manufacture and transportation of high-voltage electrical equipment. These defects can lead to insulation degradation or even failure during operation. In the early stages of insulation degradation, partial discharge (PD) occurs. PD occurs when the electric field strength in a localized area of insulation equipment reaches the breakdown field strength, resulting in discharge in that area without causing breakdown. PD damage to insulation equipment develops slowly and is a typical insulation hazard. Therefore, PD detection is used as a method to detect insulation defects. Promptly shutting down and repairing defective high-voltage electrical equipment in the early stages of PD can prevent primary insulation breakdown and potentially catastrophic power outages. Detection methods for these PD phenomena are limited in detection range due to the significant attenuation of ultrasonic signals in the insulation materials commonly used in power equipment. Furthermore, the thick casing and complex internal structure of high-voltage electrical equipment complicate on-site inspection. On the other hand, the inability to accurately locate the source of partial discharge (PD), especially when it's located near a piece of equipment's pot-type insulator, often makes it difficult to accurately determine the gas chamber in which the source resides. This complicates and increases the cost of equipment maintenance and repair. Therefore, developing an integrated PD insulation defect detection sensor that can effectively overcome these shortcomings has become a pressing technical challenge for the industry. Summary of the Invention

[0003] In response to the above-mentioned problems existing in the prior art, an embodiment of the present invention provides an integrated partial discharge insulation defect detection sensor.

[0004] In a first aspect, an embodiment of the present invention provides an integrated detection sensor for partial discharge insulation defects, comprising: a flexible thin film piezoelectric material, a first metal electrode structure and a second metal electrode structure laid on both sides of the flexible thin film piezoelectric material, a first wire connected to the first metal electrode structure, and a second wire connected to the second metal electrode structure.

[0005] Based on the contents of the above device embodiment, in the embodiment of the present invention, the integrated partial discharge insulation defect detection sensor is provided, wherein the first metal electrode structure and the second metal electrode structure are both used to output ultrasonic signals and ultra-high frequency signals.

[0006] Based on the contents of the above device embodiment, in the embodiment of the present invention, the integrated partial discharge insulation defect detection sensor is provided, wherein the first metal electrode structure and the second metal electrode structure are laid on one side of the flexible thin film piezoelectric material.

[0007] On the basis of the contents of the above-mentioned device embodiment, in the embodiment of the present invention, an integrated sensor for detecting partial discharge insulation defects is provided, wherein the flexible thin film piezoelectric material is a polyvinylidene fluoride piezoelectric film.

[0008] Based on the contents of the above-mentioned device embodiment, in the embodiment of the present invention, an integrated detection sensor for partial discharge insulation defects is provided, wherein the first metal electrode structure is a first copper interdigital electrode, and the second metal electrode structure is a second copper interdigital electrode, and the first copper interdigital electrode and the second copper interdigital electrode are printed on one side of the polyvinylidene fluoride piezoelectric film.

[0009] Based on the contents of the above device embodiment, in the embodiment of the present invention, an integrated sensor for detecting partial discharge insulation defects is provided, wherein the polyvinylidene fluoride piezoelectric film has a dielectric constant of 6, a loss tangent of 0.04, and is bendable.

[0010] Based on the contents of the above device embodiment, in the embodiment of the present invention, the integrated partial discharge insulation defect detection sensor is provided, wherein the first metal electrode structure can simultaneously receive ultrasonic signals and ultra-high frequency signals.

[0011] Based on the contents of the above device embodiment, in the integrated partial discharge insulation defect detection sensor provided in the embodiment of the present invention, the second metal electrode structure can simultaneously receive ultrasonic signals and ultra-high frequency signals.

[0012] Based on the contents of the above device embodiment, in the embodiment of the present invention, the integrated partial discharge insulation defect detection sensor is provided, wherein the output end of the first metal electrode structure can simultaneously output an ultrasonic signal and an ultra-high frequency signal.

[0013] Based on the contents of the above device embodiment, in the embodiment of the present invention, the integrated partial discharge insulation defect detection sensor is provided, wherein the output end of the second metal electrode structure can simultaneously output an ultrasonic signal and an ultra-high frequency signal.

[0014] The integrated partial discharge insulation defect detection sensor provided in an embodiment of the present invention selects a flexible thin-film piezoelectric material as a dielectric base plate, and forms a piezoelectric ultrasonic sensor and an ultra-high frequency sensor with a metal electrode structure laid thereon. The output end of the metal electrode structure can simultaneously output ultrasonic signals and ultra-high frequency signals. When detecting partial discharge insulation defects in power equipment, the integrated sensor can be built into the inner wall of the metal casing of the power equipment. Based on the difference in arrival time of the output ultrasonic signal and the ultra-high frequency signal or the difference in their corresponding frequencies, differential analysis is performed to accurately locate the partial discharge position. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0016] Figure 1 A schematic structural diagram of an integrated sensor for detecting partial discharge insulation defects provided by an embodiment of the present invention;

[0017] Figure 2 A schematic structural diagram of another integrated partial discharge insulation defect detection sensor provided by an embodiment of the present invention;

[0018] Figure 3 A schematic diagram of a specific example of a partial discharge insulation defect integrated detection sensor provided by an embodiment of the present invention;

[0019] Figure 4 A schematic diagram of the antenna standing wave ratio effect provided by an embodiment of the present invention;

[0020] Figure 5 A schematic diagram of the displacement effect of the polyvinylidene fluoride piezoelectric film under different frequencies provided by an embodiment of the present invention;

[0021] Figure 6 A schematic diagram of the local amplified displacement effect of the polyvinylidene fluoride piezoelectric film provided by an embodiment of the present invention in the 20KHz-80KHz frequency band;

[0022] Figure 7 A schematic diagram of the local amplified displacement effect of the polyvinylidene fluoride piezoelectric film provided by an embodiment of the present invention in the 100KHz-170KHz frequency band;

[0023] Figure 8 This is a simplified schematic diagram of the conformality of the integrated partial discharge insulation defect detection sensor provided by an embodiment of the present invention and the inner surface of the arc-shaped structure of the power equipment. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, 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 of the present invention. Obviously, the described embodiments are 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 ordinary technicians in this field without making creative work are within the scope of protection of the present invention. In addition, the technical features in the various embodiments or single embodiments provided by the present invention can be arbitrarily combined with each other to form a feasible technical solution. This combination is not restricted by the sequence of steps and / or structural composition mode, but must be based on the ability of ordinary technicians in this field to implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0025] The embodiment of the present invention provides a partial discharge insulation defect integrated detection sensor, see Figure 1 The device includes: a flexible thin film piezoelectric material 101, a first metal electrode structure 102 and a second metal electrode structure 103 laid on both sides of the flexible thin film piezoelectric material 101, a first wire 104 connected to the first metal electrode structure 102, and a second wire 105 connected to the second metal electrode structure 103.

[0026] Based on the above embodiment, in the integrated partial discharge insulation defect detection sensor provided in the embodiments of the present invention, both the first metal electrode structure and the second metal electrode structure are used to output ultrasonic signals and ultra-high frequency signals. It should be noted that ultra-high frequency signals refer to signals with a frequency between 300 MHz and 3 GHz.

[0027] On the basis of the above embodiment, in the embodiment of the present invention, the integrated partial discharge insulation defect detection sensor is provided, wherein the first metal electrode structure and the second metal electrode structure are laid on one side of the flexible thin film piezoelectric material. Figure 2 The first metal electrode structure 102 and the second metal electrode structure 103 are laid on one side of the flexible thin film piezoelectric material 101 , with a first wire 104 connected to the first metal electrode structure 102 and a second wire 105 connected to the second metal electrode structure 103 .

[0028] On the basis of the above-mentioned embodiment, in the integrated partial discharge insulation defect detection sensor provided in the embodiment of the present invention, the flexible thin film piezoelectric material is a polyvinylidene fluoride piezoelectric film.

[0029] Based on the above embodiment, in the integrated detection sensor for partial discharge insulation defects provided in the embodiment of the present invention, the first metal electrode structure is a first copper interdigital electrode, the second metal electrode structure is a second copper interdigital electrode, and the first copper interdigital electrode and the second copper interdigital electrode are printed on one side of the polyvinylidene fluoride piezoelectric film.

[0030] For details, please refer to Figure 3 The first metal electrode structure is a first copper interdigital electrode 302, and the second metal electrode structure is a second copper interdigital electrode 303. The first copper interdigital electrode 302 and the second copper interdigital electrode 303 are printed on one side of the polyvinylidene fluoride piezoelectric film 301. The electrode output end 304 of the first copper interdigital electrode 302 is connected to a wire, and the electrode output end 305 of the second copper interdigital electrode 303 is connected to a wire.

[0031] On the basis of the above embodiment, in the embodiment of the present invention, the integrated sensor for detecting partial discharge insulation defects is provided, wherein the polyvinylidene fluoride piezoelectric film has a dielectric constant of 6, a loss tangent of 0.04, and is bendable.

[0032] Specifically, the polyvinylidene fluoride piezoelectric film has a dielectric constant of 6, a loss tangent (tanδ) of 0.04, is bendable, and is resistant to high temperatures. Figure 4 As shown in the figure, the antenna standing wave ratio (VSWR) was measured by a vector network analyzer, and the VSWR in the 1.5GHz-3.0GHz frequency band was less than 5, indicating good performance. Figure 5 As shown in the figure, the displacement of the polyvinylidene fluoride piezoelectric film under different frequencies. The ultrasonic frequency band generated by partial discharge is generally 20KHz-200KHz, and there is a certain displacement. Figure 6 As shown, Figure 5 The local amplification displacement in the 20KHz-80KHz frequency band. Figure 7 As shown, Figure 5 Local amplification displacement in the 100KHz-170KHz frequency band.

[0033] Figure 8 This is an example of the conformal simplification of the integrated partial discharge insulation defect detection sensor and the inner surface of the arc-shaped structure of the power equipment GIS. Figure 8 The middle grey part is the arc-shaped shell of the power equipment GIS. Figure 2 The flexible thin film piezoelectric material 101 can bend into an arc shape after being conformed, so that it can better fit on the surface of the device and is easy to install.

[0034] The integrated sensor for detecting partial discharge insulation defects designed above can simultaneously output both ultrasonic and electromagnetic signals. It also meets detection requirements and performs well within both the ultrasonic and ultra-high frequency bands. This integrated ultrasonic and ultra-high frequency sensor for detecting partial discharge insulation defects addresses the issues of existing ultrasonic and ultra-high frequency sensors, which require separate detection, lack simultaneous signal output, and cannot be bent to fit around the uneven inner surface of the metal casing of power equipment, resulting in inaccurate positioning. This improves operational ease and streamlines circuitry during actual field applications, making partial discharge insulation detection in power equipment more accurate and effective.

[0035] On the basis of the above-mentioned embodiment, in the integrated partial discharge insulation defect detection sensor provided in the embodiment of the present invention, the first metal electrode structure can simultaneously receive ultrasonic signals and ultra-high frequency signals.

[0036] On the basis of the above embodiment, in the integrated partial discharge insulation defect detection sensor provided in the embodiment of the present invention, the second metal electrode structure can simultaneously receive ultrasonic signals and ultra-high frequency signals.

[0037] On the basis of the above embodiment, in the integrated partial discharge insulation defect detection sensor provided in the embodiment of the present invention, the output end of the first metal electrode structure can simultaneously output an ultrasonic signal and an ultra-high frequency signal.

[0038] On the basis of the above embodiment, in the integrated partial discharge insulation defect detection sensor provided in the embodiment of the present invention, the output end of the second metal electrode structure can output an ultrasonic signal and an ultra-high frequency signal simultaneously.

[0039] Specifically, when partial discharge occurs, the output terminals of the first and second metal electrode structures of the integrated partial discharge insulation defect detection sensor simultaneously output the ultrasonic and ultra-high frequency signals generated by the partial discharge, recording multiple sets of data. The ultrasonic and electromagnetic wave signals generated by different types of partial discharge have different pulse amplitudes, pulse counts, phase distributions, and spectra, resulting in distinct spectral characteristics. These signals can also be distinguished based on their arrival times or corresponding frequencies.

[0040] The integrated partial discharge insulation defect detection sensor provided by the present invention selects a flexible thin-film piezoelectric material as the dielectric base plate, and forms a piezoelectric ultrasonic sensor and an ultra-high frequency sensor with a metal electrode structure laid thereon. The output end of the metal electrode structure can simultaneously output ultrasonic signals and ultra-high frequency signals. When detecting partial discharge insulation defects in power equipment, the integrated sensor can be built into the inner wall of the metal casing of the power equipment. Based on the difference in arrival time of the output ultrasonic signal and the ultra-high frequency signal or the difference in their corresponding frequencies, differential analysis is performed to accurately locate the partial discharge position.

[0041] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0042] In this patent, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises..." does not preclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0043] 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 it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A partial discharge insulation defect integrated detection sensor, characterized in that: The integrated partial discharge insulation defect detection sensor can simultaneously output ultrasonic signals and electromagnetic wave signals, including: A flexible thin film piezoelectric material, wherein the flexible thin film piezoelectric material is a polyvinylidene fluoride piezoelectric film, the polyvinylidene fluoride piezoelectric film has a dielectric constant of 6, a loss tangent angle of 0.04, and is bendable; a first metal electrode structure and a second metal electrode structure, wherein the first metal electrode structure and the second metal electrode structure are laid on one side of the flexible thin-film piezoelectric material, the output end of the first metal electrode structure and the output end of the second metal electrode structure can both simultaneously output ultrasonic signals and ultra-high frequency signals, and the first metal electrode structure and the second metal electrode structure can both simultaneously receive ultrasonic signals and ultra-high frequency signals, the first metal electrode structure is a first copper interdigital electrode, and the second metal electrode structure is a second copper interdigital electrode, and the first copper interdigital electrode and the second copper interdigital electrode are printed on one side of the polyvinylidene fluoride piezoelectric film; A first wire connected to the first metal electrode structure, and a second wire connected to the second metal electrode structure.

Images