A method for testing the aging degree of composite insulators

Abstract

The present invention discloses a composite insulator aging degree testing method, which is to detect the aging degree of the composite insulator by analyzing the vibration echo characteristics of the composite insulator shed. The present invention obtains the Q value of the same insulator in two states: newly installed and after running for a period of time through the above testing method, and analyzes the change trend of the Q value to know the aging condition of the insulator.

Description

Technical Field

[0001] The invention relates to the technical field of composite insulator aging detection, and in particular to a composite insulator aging degree testing method. Background Art

[0002] Insulators play a vital role in the safe operation of power systems. Composite insulators have been widely used in power systems due to their light weight, good anti-pollution flashover performance, and high mechanical strength. However, composite insulators will age under the influence of electric fields, ultraviolet rays, acid rain, and pollution for a long time, resulting in a decrease in their electrical and mechanical properties, which can easily cause insulation flashover, leading to single-phase grounding, voltage anomalies and other faults, posing a potential threat to the power supply reliability of the power grid.

[0003] Therefore, testing the performance of composite insulators, determining the degree of insulator aging, judging whether insulators need to be replaced, eliminating power grid faults, and improving the efficiency of equipment status maintenance are all of great practical significance for ensuring the safe operation of the power system.

[0004] At present, the main detection methods for the aging status of composite insulators are:

[0005] (1) Hydrophobicity test methods, including water spray classification method, contact angle method, etc. Although the hydrophobicity test method is widely used, the former is somewhat subjective, and the latter requires the use of precise optical instruments to measure in the laboratory. This method is greatly affected by the contamination of the insulator surface and cannot effectively reflect the aging characteristics of the insulator body performance;

[0006] (2) Ultraviolet imaging method: The defect state of the insulator is determined by detecting the ultraviolet radiation radiated during corona discharge on the surface of the composite insulator. This method is simple and easy to use, but it is seriously affected by the detection distance, atmospheric pressure and ambient temperature, and cannot effectively reflect the aging characteristics of the insulator body performance;

[0007] (3) Leakage current method: by measuring the leakage current on the surface of the composite insulator, the insulation performance of the composite insulator surface is determined. However, this method is greatly affected by the contamination of the insulator surface and cannot effectively reflect the aging characteristics of the insulator body performance.

[0008] (4) Thermally stimulated current method: This method is a microscopic analysis method, but it requires the sample to be cooled with liquid nitrogen, and it is a lossy measurement, which makes on-site measurement difficult.

[0009] (5) Infrared spectroscopy: The chemical composition of a substance can be inferred by the distribution characteristics of its absorption band after being irradiated by infrared spectrum. The content of each component can also be determined based on the intensity of the characteristic absorption peak. However, the repeatability of the absorption peak intensity is not stable, which is not conducive to quantitative analysis. Summary of the invention

[0010] In order to solve the above problems, the purpose of the present application is to provide a method for testing the aging degree of composite insulators.

[0011] To achieve the purpose of the present invention, the present invention provides a method for testing the aging degree of a composite insulator.

[0012] The method is to detect the aging degree of the composite insulator by analyzing the vibration echo characteristics of the composite insulator shed.

[0013] In a preferred embodiment,

[0014] The method specifically comprises:

[0015] (1) A clamp is mounted on the shed of the composite insulator, wherein the clamp is provided with an electromagnetic excitation module and a vibration detection sensor;

[0016] (2) applying an impact force F to the clamp through the electromagnetic excitation module;

[0017] (3) Using a vibration detection sensor to monitor the vibration condition of the detection point, and performing frequency analysis on the collected vibration condition through a filter circuit, an A / D differential circuit, and an A / D conversion circuit;

[0018] The frequency analysis includes that when the impact force F is applied, the corresponding relationship between the vibration amplitude and the detection time at the detection point at 100 Hz and 1000 Hz is f(t, A), f(0.1s, A), f(0.2s, A) are obtained, and H is obtained. 100Hz＝ f(0.1s, A) / f(0.2s, A), H 1000Hz＝ f(0.1s, A) / f(0.2s, A), the ratio of the two frequencies is calculated to be Q1=H 100Hz / H 1000Hz ;

[0019] (4) Repeat the above steps (1), (2), and (3) for the same composite insulator that has been in operation for a period of time to obtain Q2; by comparing the changing trend of the Q value, the aging condition of the insulator can be known.

[0020] In a preferred embodiment, the clamp is made of hard rubber material.

[0021] In a preferred embodiment, the clamp is in the shape of a circular ring.

[0022] Compared with the prior art, the beneficial effect of the present invention is that, through the above test method, the Q value of the same insulator in two states, namely, newly installed and after running for a period of time, can be obtained, and the aging condition of the insulator can be known by analyzing the change trend of the Q value;

[0023] The aging degree of composite insulators increases with the increase of service years, showing the external characteristics of mechanical property degradation, powdering and embrittlement, which causes its vibration characteristics to decrease with the increase of service years. The amplitude attenuation of different frequencies is different. As the shed material ages and becomes brittle, the ratio Q increases;

[0024] This method detects the aging degree of composite insulators through clamp vibration detection technology and wireless sensor technology. Only clamps, laser receivers and analysis devices are needed to complete the test process, and the equipment requirements are low; it is not affected by the detection distance, atmospheric pressure, ambient temperature and humidity; the subsequent analysis work is completed through the software system, which greatly reduces the workload, and the detection method is flexible and fast; the equipment structure is small, easy to carry, convenient for on-site measurement, and does not need to cut off the composite insulator shed for measurement, which truly realizes non-destructive measurement and is highly practical. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 Shown is a schematic diagram of the structure of this application.

[0026] Figure 2 Shown is the amplitude and time relationship diagram of this application at 100Hz;

[0027] Figure 3 Shown is the amplitude and time relationship diagram of this application at 1000Hz;

[0028] In the figure, 1 is a clamp, 2 is an umbrella skirt, 3 is an electromagnetic excitation module, and 4 is a vibration detection sensor. DETAILED DESCRIPTION

[0029] In order to make the technical means implemented by the present invention easier to understand, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are only used to explain the relevant application, rather than to limit the application. It is also necessary to explain that, for the convenience of description, only the parts related to the present application are shown in the accompanying drawings.

[0030] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0031] It should be noted that, in the description of the present application, terms such as "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings. This is merely for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be understood as a limitation on the present application.

[0032] In addition, it should be noted that in the description of this application, unless otherwise clearly specified and limited, the term "installation" and the like should be understood in a broad sense, for example, it can be a fixed installation or a detachable installation.

[0033] For those skilled in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0034] Example 1

[0035] like Figure 1-Figure 3 As shown, the embodiment of the present invention utilizes the clamp vibration detection technology and the sensing technology, applies a certain magnitude of impact force to the composite insulator shed through an electromagnetic excitation module, and receives the vibration echo characteristics of the detection object through a vibration detection sensor to detect the aging degree of the composite insulator.

[0036] Through the above test method, the Q value of the same insulator in two states, newly installed and after a period of operation, can be obtained. By analyzing the change trend of the Q value, the aging condition of the insulator can be known.

[0037] The aging degree of composite insulators increases with the increase of their service years, showing the external characteristics of mechanical performance degradation, powdering and embrittlement, which leads to the decrease of their vibration characteristics with the increase of service years. The amplitude attenuation of different frequencies is different. As the shed material ages and becomes brittle, the ratio Q increases.

[0038] Example 2

[0039] This embodiment discloses a specific method based on Embodiment 1, and the steps are as follows:

[0040] (1) Install an annular clamp on the shed of the newly installed composite insulator;

[0041] The clamp is provided with an electromagnetic excitation module and a vibration detection sensor;

[0042] (2) applying an impact force F to the clamp through the electromagnetic excitation module;

[0043] (3) Using a vibration detection sensor to monitor the vibration condition of the detection point, and performing frequency analysis on the collected vibration condition through a filter circuit, an A / D differential circuit, and an A / D conversion circuit;

[0044] The frequency analysis includes that when the impact force F is applied, the corresponding relationship between the vibration amplitude and the detection time at the detection point at 100 Hz and 1000 Hz is f(t, A), f(0.1s, A), f(0.2s, A) are obtained, and H is obtained. 100Hz＝ f(0.1s, A) / f(0.2s, A), H 1000Hz＝f(0.1s, A) / f(0.2s, A), the ratio of the two frequencies is calculated to be Q1=H 100Hz / H 1000Hz ;

[0045] (4) Repeat the above steps (1), (2), and (3) for the same composite insulator that has been in operation for a period of time to obtain Q2; by comparing the changing trend of the Q value, the aging condition of the insulator can be known.

[0046] The present invention uses the above test method to obtain the Q value of the same insulator in two states: newly installed and after running for a period of time. By analyzing the change trend of the Q value, the aging condition of the insulator can be known.

[0047] The aging degree of composite insulators increases with the increase of service years, showing the external characteristics of mechanical property degradation, powdering and embrittlement, which causes its vibration characteristics to decrease with the increase of service years. The amplitude attenuation of different frequencies is different. As the shed material ages and becomes brittle, the ratio Q increases;

[0048] This method detects the aging degree of composite insulators through clamp vibration detection technology and wireless sensor technology. Only clamps, laser receivers and analysis devices are needed to complete the test process, and the equipment requirements are low; it is not affected by the detection distance, atmospheric pressure, ambient temperature and humidity; the subsequent analysis work is completed through the software system, which greatly reduces the workload, and the detection method is flexible and fast; the equipment structure is small, easy to carry, convenient for on-site measurement, and does not need to cut off the composite insulator shed for measurement, which truly realizes non-destructive measurement and is highly practical.

[0049] It should be noted that the technical solutions not described in detail in this application adopt publicly known technologies.

[0050] The above is only a preferred embodiment of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for testing the aging degree of composite insulators. It is characterized in that The method is to detect the aging degree of the composite insulator by analyzing the vibration echo characteristics of the composite insulator shed; The method specifically comprises: (1) A clamp is mounted on the shed of the composite insulator, wherein the clamp is provided with an electromagnetic excitation module and a vibration detection sensor; (2) applying an impact force F to the clamp through the electromagnetic excitation module; (3) Use a vibration detection sensor to monitor the vibration condition of the detection point, and perform frequency analysis on the collected vibration condition through a filter circuit, an A / D differential circuit, and an A / D conversion circuit; The frequency analysis includes that when the impact force F is applied, the corresponding relationship between the vibration amplitude and the detection time at the detection point at 100Hz and 1000Hz is f(t, A), f(0.1s, A), f(0.2s, A) are obtained, and the obtained H 100Hz= f(0.1s, A) / f(0.2s, A), H 1000Hz= f(0.1s, A) / f(0.2s, A), the ratio of the two frequencies is calculated to be Q1= H 100Hz / H 1000Hz ; (4) Repeat tests (1), (2), and (3) on the same composite insulator that has been in operation for a period of time to obtain Q2. By comparing the changing trends of the Q value, the aging condition of the insulator can be determined.

2. A composite insulator aging degree testing method according to claim 1, It is characterized in that The clamp is made of hard rubber material.

3. A composite insulator aging degree testing method according to claim 1, It is characterized in that The clamp is in a circular ring shape.

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