Method for manufacturing equivalent diagram for defect diagnosis of insulation pull rod of GIS circuit breaker

Abstract

The invention discloses an equivalent diagram manufacturing method for defect diagnosis of an insulating pull rod of a GIS circuit breaker. The equivalent diagram manufacturing method comprises the following steps: processing an epoxy composite insulating material into a flat-bottom hole sample block with a preset size; carrying out calibration measurement on the prepared standard sample test block; recording the sound path distance corresponding to the wave peak of the flat-bottomed hole reflection wave of each sample block and the corresponding gain when the wave height of the reflection echo reaches 50% of a screen, and drawing a practical equivalent curve of the fiber reinforced epoxy composite material. And the position, the size and the severity of the insulation defect can be visually displayed. The manufacturing method comprises the steps of sample preparation, data acquisition, processing, equivalent diagram generation and the like, wherein the equivalent diagram provides comprehensive evaluation for the insulation state. The insulation problem can be timely identified, and powerful support is provided for maintenance and preventive maintenance.

Description

Technical Field

[0001] The present invention belongs to the technical field of intelligent operation and maintenance of electric power equipment, and in particular relates to an equivalent diagram preparation method for insulating rod defect diagnosis of a GIS circuit breaker. Background Art

[0002] The insulating rod is a key insulating component in the GIS circuit breaker. It is a structural element used to transmit movement from the grounded part to the high-potential part to achieve the on-off of the electrical connection. The insulating rod is generally made of fiber-reinforced epoxy composite materials. Some defects may occur during the production, transportation and installation process, such as air gap defects caused by insufficient impregnation of epoxy resin and fiber during production, and bonding interface defects caused by abnormal force during transportation and installation. Due to the existence of these defects, obvious electric field distortion will occur in the insulating rod under operating conditions, partial discharge may occur in the defective part, and strong mechanical stress will cause the defects of the insulating rod to further expand, eventually causing the rod insulation failure.

[0003] In recent years, ultrasonic testing technology has been widely used for internal defect detection of various insulators due to its advantages such as good directionality and easy operation. However, few researchers have conducted in-depth discussions on ultrasonic testing technology for fiber-reinforced epoxy composites. In product factory inspection and live operation and daily maintenance of power equipment, there is still a lack of effective means to diagnose internal defects of fiber-reinforced epoxy composites. This makes it difficult to accurately locate the air gap defects inside the insulating pull rod, and it is difficult to determine the size and severity of the defects. In view of this situation, it is urgent to propose a method that is easy to operate and has excellent results to solve the above problems. Summary of the invention

[0004] The present invention provides an equivalent diagram preparation method for insulating rod defect diagnosis of GIS circuit breaker, especially for epoxy composite insulating materials with reinforced fibers, and aims to propose an ultrasonic detection method which is easy to operate and has reliable effect and can be used in product factory inspection, live operation of power equipment and daily maintenance.

[0005] The present invention provides an equivalent diagram preparation method for insulating rod defect diagnosis of a GIS circuit breaker, comprising:

[0006] Processing epoxy composite insulation material into flat bottom hole coupons of preset size;

[0007] Carrying out calibration measurement on the prepared standard sample block;

[0008] The acoustic path distance corresponding to the peak of the flat-bottom hole reflection wave of each sample block and the gain corresponding to when the reflected echo wave height reaches 50% of the screen are recorded, and the practical equivalent curve of the fiber-reinforced epoxy composite material is drawn.

[0009] Further, the epoxy composite insulating material is processed into a flat-bottom hole sample block of a preset size, specifically:

[0010] The epoxy composite insulating material is processed into a 50mm thick test block to ensure that the surface is flat and smooth. Holes are drilled on the bottom with a milling cutter to make flat-bottom hole test blocks with diameters of 1mm, 2mm, and 3mm and depths of 20mm, 25mm, 30mm, 35mm, 40mm, and 45mm respectively.

[0011] Furthermore, the prepared standard sample block is calibrated and measured, specifically:

[0012] A longitudinal wave straight probe with a frequency of 1.25MHz and a chip diameter of 14mm is used. Engine oil is used as the coupling agent. 50% of the screen wave height is used as the standard height. The probe is aimed at the defect position of the flat-bottom hole and scanned back and forth. When the echo height reaches the highest, the gain of the ultrasonic flaw detector is adjusted to make the echo height of the flat-bottom hole 50% of the screen wave height. The gain value and the sound path of the flat-bottom hole are recorded, and the operation is performed on each flat-bottom hole in turn.

[0013] The present invention discloses an equivalent diagram production method for GIS circuit breaker insulation rod defect diagnosis, which can intuitively display the location, size and severity of insulation defects. The production method includes the steps of sample preparation, data collection, processing, equivalent diagram generation, etc., wherein the equivalent diagram provides a comprehensive assessment of the insulation status. This technology helps to identify insulation problems in a timely manner and provides strong support for repair and preventive maintenance. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. 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 creative work.

[0015] Figure 1 A schematic diagram of a flat-bottom hole sample block provided by an embodiment of the present invention;

[0016] Figure 2 A schematic diagram of a flat bottom hole reflection echo of an instrument provided in one embodiment of the present invention;

[0017] Figure 3 A fiber-reinforced epoxy composite insulation defect equivalent curve diagram of a specific embodiment of the present invention is provided. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution 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 creative work are within the scope of protection of the present invention.

[0019] The present application discloses an equivalent diagram preparation method for insulating pull rod defect diagnosis of GIS circuit breaker, comprising: processing epoxy composite insulating material into flat-bottom hole test blocks of preset size; calibrating and measuring the prepared standard test blocks; recording the sound path distance corresponding to the flat-bottom hole reflection wave peak of each test block and the gain corresponding to the reflected echo wave height reaching 50% of the screen, and drawing a practical equivalent curve of the fiber-reinforced epoxy composite material.

[0020] Specifically, the flat bottom hole specimen block is as follows Figure 1 The epoxy composite insulation material is processed into a flat bottom hole specimen block of a preset size, specifically:

[0021] The epoxy composite insulating material is processed into a 50mm thick test block to ensure that the surface is flat and smooth. Holes are drilled on the bottom with a milling cutter to make flat-bottom hole test blocks with diameters of 1mm, 2mm, and 3mm and depths of 20mm, 25mm, 30mm, 35mm, 40mm, and 45mm respectively.

[0022] The prepared standard test block is calibrated and measured, specifically:

[0023] A longitudinal wave straight probe with a frequency of 1.25MHz and a chip diameter of 14mm is used. Engine oil is used as the coupling agent. 50% of the screen wave height is used as the standard height. The probe is aimed at the defect position of the flat-bottom hole and scanned back and forth. When the echo height reaches the highest, the gain of the ultrasonic flaw detector is adjusted to make the echo height of the flat-bottom hole 50% of the screen wave height. The gain value and the sound path of the flat-bottom hole are recorded, and the operation is performed on each flat-bottom hole in turn.

[0024] In a specific embodiment,

[0025] The instrument echo diagram of a flat bottom hole defect with a diameter of 3mm and a depth of 35mm is shown in the attached figure. Figure 2 As shown, Figure 2 The left picture shows that the flat bottom hole defect reflection wave reaches the highest value after the probe is moved. At this time, the instrument gain is 40dB. Adjust the instrument gain to 50.6dB to make the flat bottom hole defect echo reach 50% screen wave height. Figure 3 As shown, record the gain value and the sound path of the flat-bottom hole.

[0026] How to use the equivalence diagram:

[0027] Defect equivalent curves of defects with different pore sizes in fiber reinforced epoxy composites are shown in Figure 2. Figure 3 As shown in the figure, when a defect echo is found somewhere during the flaw detection process, the depth position of the air gap defect is first determined according to the sound path distance corresponding to the peak of the defect reflection wave, and then the gain can be adjusted to adjust the defect echo to 50% of the wave height. The gain value is read and compared with the defect equivalent curve under the probe to obtain the size equivalent value of the defect. This curve provides a test basis for the defect assessment in fiber-reinforced epoxy composite materials. When the sound path position corresponding to the peak of the reflection wave is 45mm, it indicates that the depth of the defect is 45mm. Further adjust the gain so that the peak of the reflection wave reaches 50% of the screen height, and record the gain value at this time. When the gain value is 73dB, it can be determined that the defect size is approximately 1mm; when the gain value is 71dB, it can be determined that the defect size is approximately 2mm; when the gain value is 65dB, it can be determined that the defect size is approximately 3mm.

[0028] 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 embodiments of the present invention.

Claims

1. A method for preparing an equivalent diagram for diagnosing defects in insulating rods of GIS circuit breakers, characterized in that: include: Processing epoxy composite insulation material into flat bottom hole coupons of preset size; Carrying out calibration measurement on the prepared standard sample block; The acoustic path distance corresponding to the peak of the flat-bottom hole reflection wave of each sample block and the gain corresponding to when the reflected echo wave height reaches 50% of the screen are recorded, and the practical equivalent curve of the fiber-reinforced epoxy composite material is drawn.

2. The method for preparing an equivalent diagram for insulating rod defect diagnosis of a GIS circuit breaker according to claim 1, characterized in that: The epoxy composite insulation material is processed into a flat bottom hole specimen block of preset size, specifically: The epoxy composite insulating material is processed into a 50mm thick test block to ensure that the surface is flat and smooth. Holes are drilled on the bottom with a milling cutter to make flat-bottom hole test blocks with diameters of 1mm, 2mm, and 3mm and depths of 20mm, 25mm, 30mm, 35mm, 40mm, and 45mm respectively.

3. The method for preparing an equivalent diagram for insulating rod defect diagnosis of a GIS circuit breaker according to claim 1, characterized in that: The prepared standard test block is calibrated and measured, specifically: A longitudinal wave straight probe with a frequency of 1.25MHz and a chip diameter of 14mm is used. Engine oil is used as the coupling agent. 50% of the screen wave height is used as the standard height. The probe is aimed at the defect position of the flat-bottom hole and scanned back and forth. When the echo height reaches the highest, the gain of the ultrasonic flaw detector is adjusted to make the echo height of the flat-bottom hole 50% of the screen wave height. The gain value and the sound path of the flat-bottom hole are recorded, and the operation is performed on each flat-bottom hole in turn.

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