A method for analyzing the state of GIS pot-type insulators

Abstract

The present disclosure discloses a method for analyzing the state of a GIS pot insulator, including: setting excitation points and response points on the pot insulator to be measured during new commissioning, knocking the excitation points to generate an excitation signal V<subgt;1< / subgt>, collecting the response signal V<subgt;2< / subgt> at the response points, and obtaining the transfer function f<subgt;1< / subgt> of the pot insulator to be measured during new commissioning according to the excitation signal V<subgt;1< / subgt> and the response signal V<subgt;2< / subgt>; obtaining the transfer function f<subgt;2< / subgt> of the pot insulator to be measured in the initial stage of operation and the transfer function f<subgt;3< / subgt> of the pot insulator to be measured in the later stage of operation of the same model according to the operation method in step 1; calculating the state index P of the pot insulator to be measured in the later stage of operation according to the obtained transfer functions f<subgt;1< / subgt>, f<subgt;2< / subgt> and f<subgt;3< / subgt>; comparing the state index P with a threshold value, and judging whether there are defects and the severity of the defects of the pot insulator to be measured in the later stage of operation according to the comparison result.

Description

Technical Field

[0001] The present disclosure belongs to the technical field of electrical equipment detection, and particularly relates to a method for analyzing the state of a GIS basin insulator. Background Art

[0002] Gas-insulated metal-enclosed switchgear (GIS) is one of the most important equipment in the current power system, and its operation reliability is directly related to the safety and stability of the power grid system. During the operation of GIS, various types of dirt such as dust and metal particles will be deposited on the surface of the basin insulator, and at the same time, internal defects such as internal cracks will also be generated due to the release of residual stress during the manufacturing process; the presence of surface dirt or internal defects makes the basin insulator prone to discharge during operation, resulting in insulation failure. Therefore, how to master its state during operation is an urgent problem to be solved.

[0003] To address this problem, the conventional method is to use ultra-high frequency or ultrasonic methods for partial discharge detection. However, partial discharge is often not sensitive enough to the defects of the basin, and once discharge occurs, it will quickly lead to flashover, lacking enough time to deal with the defective basin. Analyzing the state of the basin insulator using the modal characteristics of the basin insulator is a feasible method. Its basic principle is that once the state of the surface or inside of the basin insulator changes, its mode will change, and the degree of mode change can be characterized by detecting the vibration transfer function. However, existing modal detection methods can only judge whether there are defects in the basin insulator by directly observing the change of the vibration transfer function curve, but the severity of its defects cannot be quantitatively analyzed, which is not conducive to the operators to make an accurate judgment on its state. Summary of the Invention

[0004] Aiming at the deficiencies in the prior art, the purpose of the present disclosure is to provide a method for analyzing the state of a GIS basin insulator. This method calculates its state index by obtaining the transfer function of the basin insulator at different commissioning stages, so as to be able to quantitatively analyze whether there are defects in the basin insulator and its state level.

[0005] To achieve the above purpose, the present disclosure provides the following technical solutions:

[0006] A method for analyzing the state of a GIS basin insulator includes the following steps:

[0007] S100: Set an excitation point and a response point on the basin insulator to be tested newly put into operation, strike the excitation point to generate an excitation signal V1, collect the response signal V2 at the response point, and obtain the transfer function f1 of the basin insulator to be tested newly put into operation according to the excitation signal V1 and the response signal V2;

[0008] S200: Obtain the transfer function f2 of the to-be-tested pot insulator in the initial operation stage of the same model and the transfer function f3 of the to-be-tested pot insulator in the later operation stage according to the operation method in step S100;

[0009] S300: Calculate the state index P of the to-be-tested pot insulator in the later operation stage according to the obtained transfer functions f1, f2 and f3;

[0010] S400: Compare the state index P with the threshold value, and judge whether there are defects and the severity of the defects of the to-be-tested pot insulator in the later operation stage according to the comparison result.

[0011] Preferably, in step S100, obtaining the transfer function f1 of the newly-operated to-be-tested pot insulator according to the excitation signal V1 and the response signal V2 includes the following steps:

[0012] S101: Perform Fourier transform on the excitation signal V1 to obtain the frequency-domain function S1(w)=FFT(V1);

[0013] S102: Perform Fourier transform on the response signal V2 to obtain the frequency-domain function R1(w)=FFT(V2);

[0014] S103: Calculate the transfer function f1, that is

[0015] Preferably, in step S300, the state index P is expressed as:

[0016]

[0017] where i represents the data point and n represents the number of data points.

[0018] Preferably, in step S400, the threshold value is set to 1.5.

[0019] Preferably, in step S400, if the P value is greater than the threshold value, judge the severity of the defects of the to-be-tested pot insulator in the later operation stage according to the size of the P value.

[0020] The present disclosure also provides a GIS pot insulator defect analysis device, including:

[0021] An acquisition module, which is respectively used to acquire the transfer function f1 of the newly-operated to-be-tested pot insulator of the same model, the transfer function f2 of the to-be-tested pot insulator in the initial operation stage, and the transfer function f3 of the to-be-tested pot insulator in the later operation stage;

[0022] A calculation module, which is used to calculate the state index P of the to-be-tested pot insulator in the later operation stage according to the obtained transfer functions f1, f2 and f3;

[0023] An analysis module is configured to compare the state index P with a threshold value, and determine whether there are defects in the pot-type insulator to be tested in the later stage of operation and the severity of the defects according to the comparison result.

[0024] Preferably, the acquisition module includes a force hammer, a vibration acceleration sensor, a data acquisition card, and a host computer. The force hammer and the vibration acceleration sensor are located at both ends of the pot-type insulator to be tested, and the force hammer and the vibration acceleration sensor are connected to the host computer through the data acquisition card.

[0025] Compared with the prior art, the beneficial effects brought by the present disclosure are as follows:

[0026] By acquiring the transfer function of the pot-type insulator at different operation stages and calculating its state index, the present disclosure can quantitatively analyze whether there are defects in the pot-type insulator and the severity of the defects. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a flowchart of a method for analyzing the state of a GIS pot-type insulator provided by an embodiment of the present disclosure;

[0028] Figure 2 is a schematic structural diagram of the acquisition module;

[0029] Figure 3 is a schematic diagram of the vibration transfer function curve of the pot-type insulator in different states. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0030] The following will refer to the attached Figures 1 to 3 The specific embodiments of the present disclosure will be described in detail. Although specific embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0031] It should be noted that certain terms are used in the specification and claims to refer to specific components. Those skilled in the art should understand that technicians may use different terms to refer to the same component. The specification and claims do not distinguish components based on the difference in terms, but on the difference in function of the components. As used throughout the specification and claims, the terms "comprising" or "including" are open-ended terms and should be interpreted as "including but not limited to". The subsequent description of the specification is for the purpose of describing the preferred embodiments of implementing the present disclosure, but the description is for the general purpose of the specification and is not intended to limit the scope of the present disclosure. The scope of protection of the present disclosure shall be defined by the appended claims.

[0032] For ease of understanding the embodiments of the present disclosure, the following will further explain and illustrate with specific embodiments in conjunction with the accompanying drawings, and the accompanying drawings do not limit the embodiments of the present disclosure.

[0033] In one embodiment, as Figure 1 shown, the present disclosure provides a method for analyzing the state of a GIS pot insulator, including the following steps:

[0034] S100: Set excitation points and response points on the newly commissioned pot insulator to be measured, strike the excitation points to generate an excitation signal V1, collect the response signal V2 at the response points, and obtain the transfer function f1 of the newly commissioned pot insulator to be measured according to the excitation signal V1 and the response signal V2;

[0035] S200: Obtain the transfer function f2 of the pot insulator to be measured in the initial stage of operation and the transfer function f3 of the pot insulator to be measured in the later stage of operation of the same model according to the operation method of step S100;

[0036] S300: Calculate the state index P of the pot insulator to be measured in the later stage of operation according to the obtained transfer functions f1, f2, and f3;

[0037] S400: Compare the state index P with a threshold value, and judge whether there are defects and the severity of the defects of the pot insulator to be measured in the later stage of operation according to the comparison result.

[0038] The above embodiments constitute the complete technical solution of the present disclosure. This solution can quantitatively analyze whether there are defects and the defect level of the pot insulator by obtaining the transfer functions of the pot insulators in different operation stages and calculating their state indices, thereby overcoming the existing problem that it is impossible to accurately judge the severity of the defects of the pot insulator only by observing the transfer function curve.

[0039] In another embodiment, in step S100, the obtaining the transfer function f1 of the newly commissioned pot insulator to be measured according to the excitation signal V1 and the response signal V2 includes the following steps:

[0040] S101: Perform Fourier transform on the excitation signal V1 to obtain the frequency-domain function S1(w) = FFT(V1);

[0041] S102: Perform Fourier transform on the response signal V2 to obtain the frequency-domain function R1(w) = FFT(V2);

[0042] S103: Calculate the transfer function f1, that is

[0043] This embodiment presents the process of obtaining the transfer function f1. Similarly, for the acquisition of the transfer function f2, excitation points and response points need to be set on the pot-type insulator to be measured in the initial operation period (in this industry, generally, the operation duration of 1 - 6 months is set as the initial operation period). Strike the excitation point to generate an excitation signal V2, collect the response signal V2 at the response point, perform Fourier transform on the excitation signal V2 to obtain the frequency-domain function S2(w), that is, S2(w) = FFT(V1); perform Fourier transform on the response signal V2 to obtain the frequency-domain function R2(w), that is, R2(w) = FFT(V2); then there is For the acquisition of the transfer function f3, excitation points and response points need to be set on the pot-type insulator to be measured in the later operation period (in this industry, generally, the operation duration greater than 6 months is set as the later operation period). Strike the excitation point to generate an excitation signal V3, collect the response signal V3 at the response point, perform Fourier transform on the excitation signal V3 to obtain the frequency-domain function S3(w), that is, S3(w) = FFT(V1); perform Fourier transform on the response signal V3 to obtain the frequency-domain function R3(w), that is, R3(w) = FFT(V2), then there is

[0044] In another embodiment, in step S300, the state index P is expressed as:

[0045]

[0046] where i represents the data point and n represents the number of data points.

[0047] In another embodiment, in step S400, the threshold is set to 1.5.

[0048] This embodiment briefly describes the process of setting this threshold: First, perform a modal test on a clean pot-type insulator to obtain a modal curve, then artificially apply different degrees of contamination and artificially create defects such as different degrees of cracks, use different qualities of contamination to represent different severities, then perform modal tests under different severities of contamination, calculate the P value, and through statistical analysis, it is considered that setting the threshold to 1.5 is the most reasonable.

[0049] In another embodiment, in step S400, if the P value is greater than or equal to the threshold, then judge the severity of the defects of the pot-type insulator to be measured in the later operation period according to the size of the P value.

[0050] This embodiment conducts tapping tests on multiple pot-type insulators at different stages of commissioning, obtains relevant test data, and obtains the following conclusions through data analysis and comparison with the degree of defects of the pot-type insulators themselves: if the P value is greater than 1.5 and less than or equal to 3, it is considered that the pot-type insulator has defects such as surface contamination and internal cracks, and its condition is in the general stage; if the P value is greater than 3 and less than or equal to 6, it is considered that the condition of the pot-type insulator is in the dangerous stage; if the P value is greater than 6, it is considered that the condition of the pot-type insulator is in the serious stage.

[0051] In another embodiment, the present disclosure further provides a GIS pot-type insulator defect analysis device, comprising:

[0052] The acquisition module is used to obtain the transfer function f1 of the newly commissioned pot-type insulator to be tested, the transfer function f2 of the pot-type insulator to be tested in the early stage of commissioning, and the transfer function f3 of the pot-type insulator to be tested in the late stage of commissioning;

[0053] A calculation module is used to calculate the state index P of the pot-type insulator to be tested in the later stage of commissioning based on the obtained transfer functions f1, f2 and f3;

[0054] The analysis module is used to compare the state index P with the threshold value, and judge whether the pot-type insulator to be tested in the later stage of commissioning has defects and the severity of the defects based on the comparison results.

[0055] In another embodiment, Figure 2 As shown, the acquisition module includes a hammer 3, a vibration acceleration sensor 4, an acquisition card and a host computer. The hammer and the vibration acceleration sensor are located at both ends of the pot-type insulator 2 to be tested, and the hammer and the vibration acceleration sensor are connected to the host computer through the acquisition card.

[0056] In this embodiment, when the hammer 3 strikes the excitation point of the pot insulator 2 on the GIS housing 1, an excitation signal is generated. The excitation signal is collected by the sensor provided by the hammer 3, and the vibration acceleration sensor collects the response signal at the response point of the pot insulator. The excitation signal and the response signal are collected by the acquisition card and transmitted to the host computer. The host computer can display the excitation signal and the response signal. The host computer has built-in data processing software, which can perform Fourier transform on the excitation signal and the response signal to obtain the transfer function, and can calculate the state index of the pot insulator based on the transfer function.

[0057] Taking a pot-type insulator to be tested as an example, the existing method of observing the transfer function curve and the method disclosed in the present disclosure are compared and explained.

[0058] use Figure 2The device shown respectively obtains the transfer function f1 of the pot insulator to be measured when it is newly put into operation, the transfer function f2 when it has been in operation for 3 months, and the transfer function f3 when it has been in operation for 7 months. Among them, the transfer function curves corresponding to the transfer functions f1, f2, and f3 are as Figure 3 shown. When the frequency of the vibration signal collected by the vibration acceleration sensor after passing through the transfer function calculation is in the range of 1500 - 4000 Hz, the vibration amplitude of the pot insulator when it is newly put into operation is greater than its vibration amplitude in the initial stage and the later stage of operation, and the vibration amplitude of the pot insulator in the initial stage of operation is greater than its vibration amplitude in the later stage of operation. From this, it can be explained that there are defects such as dirt on the surface of the pot insulator or cracks inside. However, according to this curve graph, it is difficult to make a clear quantitative judgment on the state of the pot insulator. According to the method described in the present disclosure, the state index of the pot insulator can be obtained as 5.4 according to this graph. According to the defect level described above, it can be judged that the state of the pot insulator is in a dangerous stage.

[0059] The above has introduced in detail a method for analyzing the state of a GIS pot insulator provided by the present invention. Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those skilled in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A method for analyzing the state of a GIS pot insulator, comprising the following steps: S100: Set an excitation point and a response point on the newly commissioned pot insulator to be measured, strike the excitation point to generate an excitation signal V1, collect the response signal V2 at the response point, and obtain the transfer function of the newly commissioned pot insulator to be measured based on the excitation signal V1 and the response signal V2 f 1; Obtaining the transfer function of a newly commissioned pot insulator under test based on the excitation signal V1 and the response signal V2 f 1 includes the following steps: S101: Perform Fourier transform on the excitation signal V1 to obtain the frequency-domain function S1(w) = FFT(V1); S102: Perform Fourier transform on the response signal V2 to obtain the frequency-domain function R1(w) = FFT(V2); S103: Calculate the transfer function f 1, that is ; S200: Obtain the transfer functions of the pot-type insulators to be tested in the initial operation stage of the same model according to the operation method in step S100 f 2 and the transfer functions of the pot-type insulators to be tested in the later operation stage f 3; S300: Calculate the state index P of the pot insulator to be measured in the later stage of operation according to the obtained transfer function f 1、 f 2 and f 3 to calculate the state index P of the pot insulator to be measured in the later stage of operation; The state index P is expressed as: ； Among them, i represents a data point, n represents the number of data points; S400: Compare the state index P with a threshold, and judge whether there are defects and the severity of the defects of the pot insulator to be measured in the later operation period according to the comparison result; The threshold is set to 1.

5. If the P value is greater than or equal to the threshold, judge the severity of the defects of the pot insulator to be measured in the later operation period according to the size of the P value; if the P value is greater than 1.5 and less than or equal to 3, it is considered that the pot insulator has defects such as surface contamination and internal cracks, and the state is in the general stage; if the P value is greater than 3 and less than or equal to 6, it is considered that the state of the pot insulator is in the dangerous stage; if the P value is greater than 6, it is considered that the state of the pot insulator is in the serious stage.

2. A GIS pot insulator defect analysis device for implementing the method according to claim 1, comprising: An acquisition module, which is respectively used to acquire the transfer functions of newly commissioned pot-type insulators to be tested of the same model f 1. The transfer function of the pot-type insulator to be tested in the initial stage of operation f 2. And the transfer function of the pot-type insulator to be tested in the later stage of operation f 3; A calculation module, configured to calculate a state index P of a basin insulator to be measured in a later stage of commissioning according to the obtained transfer function f 1、 f 2 and f 3 to calculate the state index P of the basin insulator to be measured in the later stage of commissioning; An analysis module, configured to compare the state index P with a threshold, and judge whether there are defects and the severity of the defects of the pot insulator to be measured in the later operation period according to the comparison result.

3. The device according to claim 2, wherein, The acquisition module includes a force hammer, a vibration acceleration sensor, a data acquisition card and a host computer. The force hammer and the vibration acceleration sensor are located at both ends of the pot insulator to be measured, and the force hammer and the vibration acceleration sensor are connected to the host computer through the data acquisition card.

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