Partial discharge defect method, device and equipment based on perfluoroisobutyronitrile as insulating medium

Abstract

The invention relates to a partial discharge defect method, a partial discharge defect device and partial discharge defect equipment based on perfluoroisobutyronitrile as an insulating medium. The method comprises the following steps: constructing a test platform and acquiring partial discharge parameters; controlling the test platform to perform partial discharge simulation on the insulating medium according to the partial discharge parameter to obtain a partial discharge pulse signal; extracting time domain and frequency domain data from the partial discharge pulse signal as partial discharge data, and constructing a phase resolution graph according to the partial discharge data; extracting identification data from the phase resolution spectrum; and identifying the partial discharge defect type of the insulating medium according to the identification data. The method comprises the following steps of: acquiring a partial discharge pulse signal for partial discharge simulation by taking perfluoroisobutyronitrile as an insulating medium, extracting partial discharge data on a time domain and a frequency domain from the partial discharge pulse signal, and forming a phase resolution spectrum by using the data; and identifying the partial discharge defect in the environment-friendly insulating gas such as perfluoroisobutyronitrile according to the identification data obtained on the phase resolution spectrum.

Description

Technical Field

[0001] The present application relates to the technical field of partial discharge defect identification, and in particular to a partial discharge defect method, device and equipment based on perfluoroisobutyronitrile as an insulating medium. Background Art

[0002] In the field of high voltage and insulation technology, gas-insulated switchgear GIS is used to improve the reliability of power systems. Sulfur hexafluoride SF6 has excellent insulation properties, including excellent dielectric strength and arc extinguishing performance. Therefore, sulfur hexafluoride SF6 is widely used as an insulator in gas-insulated power equipment. However, its use is constrained by environmental protection because its global warming potential GWP is 23,900 times that of carbon dioxide CO2. Therefore, some research has been conducted to develop environmentally friendly alternative gases. Perfluoroisobutyronitrile C4F7N, an environmentally friendly gas, is used in gas-insulated switchgear GIS as one of the most popular substitutes for SF6.

[0003] In recent years, gas-insulated electrical equipment such as gas-insulated metal-enclosed switchgear using environmentally friendly insulating gas perfluoroisobutyronitrile C4F7N as the insulating medium has gradually begun to be put into production. However, although the insulation properties of perfluoroisobutyronitrile C4F7N have been studied, there are few studies on its partial discharge PD characteristics. Partial discharge PD is a manifestation of the initial insulation degradation of power equipment before insulation breakdown. In addition, identifying the defects of partial discharge PD once it is detected is very important for field engineers to make maintenance decisions within GIS. At present, various partial discharge characteristics of sulfur hexafluoride SF6 have been studied in engineering practice to determine the type of partial discharge defects. However, research on the partial discharge PD characteristics of perfluoroisobutyronitrile C4F7N is very limited.

[0004] Therefore, it is necessary to study the PD characteristics of perfluoroisobutyronitrile C4F7N and identify the defect type of PD based on the PD signal. Summary of the invention

[0005] The present application provides a method, device and equipment for local discharge defects based on perfluoroisobutyronitrile as an insulating medium, which is used to solve the technical problem that there is no local discharge defect identification for perfluoroisobutyronitrile C4F7N, an environmentally friendly gas.

[0006] In order to achieve the above objectives, this application provides the following technical solutions:

[0007] On the one hand, a method for partial discharge defects based on perfluoroisobutyronitrile as an insulating medium is provided, comprising the following steps:

[0008] Construct a test platform for partial discharge using perfluoroisobutyronitrile as the insulating medium and obtain partial discharge parameters;

[0009] Controlling the test platform to perform partial discharge simulation on the insulating medium according to the partial discharge parameters to obtain a partial discharge pulse signal;

[0010] Extracting time domain and frequency domain data from the partial discharge pulse signal as partial discharge data, and constructing a phase-resolved spectrum according to the partial discharge data; extracting identification data from the phase-resolved spectrum, wherein the identification data includes an average discharge amount, a pulse count, and a discharge pulse phase angle;

[0011] The partial discharge defect type of the insulating medium is identified according to the identification data.

[0012] Preferably, identifying the partial discharge defect type of the insulating medium according to the identification data comprises:

[0013] If the average discharge amount is a first charge threshold, the pulse count is a first count threshold, and the discharge pulse phase angle is a first phase threshold, then the local discharge defect type is a particle defect;

[0014] If the average discharge amount is the second charge threshold, the pulse count is the second count threshold, and the discharge pulse phase angle is the second phase threshold, then the local discharge defect type is a solid metal protrusion defect;

[0015] If the average discharge amount is a third charge threshold, the pulse count is a third count threshold, and the discharge pulse phase angle is a third phase threshold, then the local discharge defect type is a contamination defect;

[0016] If the average discharge amount is a fourth charge threshold, the pulse count is a fourth count threshold, and the discharge pulse phase angle is a fourth phase threshold, then the local discharge defect type is an air gap defect.

[0017] Preferably, the first charge threshold is 459mV, the first count threshold is 183N / s, and the first phase threshold is 0°~360°; and / or, the second charge threshold is 32mV, the second count threshold is 42N / s, and the second phase threshold is 61°~102°; and / or, the third charge threshold is 42mV, the third count threshold is 504N / s, and the third phase threshold is 46°~130° and 254°~302°; and / or, the fourth charge threshold is 244mV, the fourth count threshold is 187N / s, and the fourth phase threshold is 16°~118° and 182°~254°.

[0018] Preferably, the test platform includes: an industrial frequency transformer, a protective resistor, a simulated gas chamber, a voltage-dividing capacitor, a coupling capacitor, a detection element and an oscilloscope, the industrial frequency transformer is also connected to an inductive voltage regulator, the first end of the industrial frequency transformer is connected to the first end of the protective resistor, the second end of the protective resistor is respectively connected to the first end of the simulated gas chamber, the first end of the voltage-dividing capacitor and the first end of the coupling capacitor, the second end of the coupling capacitor is respectively connected to the first end of the detection element and the oscilloscope, the second end of the detection element, the second end of the simulated gas chamber, the second end of the voltage-dividing capacitor and the second end of the industrial frequency transformer are grounded.

[0019] Preferably, the local discharge parameters include the power frequency voltage of the power frequency transformer, the transformation ratio of the power frequency transformer, the capacity of the power frequency transformer, the secondary side rated current of the power frequency transformer, the resistance value of the protection resistor, the voltage divider ratio of the voltage divider capacitor, the high-frequency current component of the coupling capacitor, the impedance of the detection element, the sampling rate and the analog bandwidth.

[0020] In yet another aspect, a partial discharge defect device based on perfluoroisobutyronitrile as an insulating medium is provided, comprising a platform construction and parameter acquisition module, a discharge simulation module, a data extraction module and a defect identification module;

[0021] The platform construction and parameter acquisition module is used to construct a test platform for partial discharge using perfluoroisobutyronitrile as an insulating medium, and to obtain partial discharge parameters;

[0022] The discharge simulation module is used to control the test platform to perform partial discharge simulation on the insulating medium according to the partial discharge parameters to obtain a partial discharge pulse signal;

[0023] The data extraction module is used to extract time domain and frequency domain data from the partial discharge pulse signal as partial discharge data, and construct a phase-resolved spectrum according to the partial discharge data; extract identification data from the phase-resolved spectrum, and the identification data includes an average discharge amount, a pulse count and a discharge pulse phase angle;

[0024] The defect identification module is used to identify the partial discharge defect type of the insulating medium according to the identification data.

[0025] Preferably, the defect identification module is also used to determine that the local discharge defect type is a particle defect based on the average discharge amount being a first charge threshold, the pulse count being a first count threshold and the discharge pulse phase angle being a first phase threshold; or that the local discharge defect type is a solid metal protrusion defect based on the average discharge amount being a second charge threshold, the pulse count being a second count threshold and the discharge pulse phase angle being a second phase threshold; or that the local discharge defect type is a contamination defect based on the average discharge amount being a third charge threshold, the pulse count being a third count threshold and the discharge pulse phase angle being a third phase threshold; or that the local discharge defect type is an air gap defect based on the average discharge amount being a fourth charge threshold, the pulse count being a fourth count threshold and the discharge pulse phase angle being a fourth phase threshold.

[0026] Preferably, the first charge threshold is 459mV, the first count threshold is 183N / s, and the first phase threshold is 0°~360°; and / or, the second charge threshold is 32mV, the second count threshold is 42N / s, and the second phase threshold is 61°~102°; and / or, the third charge threshold is 42mV, the third count threshold is 504N / s, and the third phase threshold is 46°~130° and 254°~302°; and / or, the fourth charge threshold is 244mV, the fourth count threshold is 187N / s, and the fourth phase threshold is 16°~118° and 182°~254°.

[0027] Preferably, the test platform includes: an industrial frequency transformer, a protective resistor, a simulated gas chamber, a voltage-dividing capacitor, a coupling capacitor, a detection element and an oscilloscope, the industrial frequency transformer is also connected to an inductive voltage regulator, the first end of the industrial frequency transformer is connected to the first end of the protective resistor, the second end of the protective resistor is respectively connected to the first end of the simulated gas chamber, the first end of the voltage-dividing capacitor and the first end of the coupling capacitor, the second end of the coupling capacitor is respectively connected to the first end of the detection element and the oscilloscope, the second end of the detection element, the second end of the simulated gas chamber, the second end of the voltage-dividing capacitor and the second end of the industrial frequency transformer are grounded; and / or, the partial discharge parameters include the industrial frequency voltage of the industrial frequency transformer, the transformation ratio of the industrial frequency transformer, the capacity of the industrial frequency transformer, the secondary side rated current of the industrial frequency transformer, the resistance of the protective resistor, the voltage-dividing ratio of the voltage-dividing capacitor, the high-frequency current component of the coupling capacitor, the impedance of the detection element, the sampling rate and the analog bandwidth.

[0028] In another aspect, a terminal device is provided, comprising a processor and a memory;

[0029] The memory is used to store program codes and transmit the program codes to the processor;

[0030] The processor is used to execute the above-mentioned partial discharge defect method based on perfluoroisobutyronitrile as an insulating medium according to the instructions in the program code.

[0031] The method, device and equipment for detecting partial discharge defects based on perfluoroisobutyronitrile as an insulating medium. The method for detecting partial discharge defects based on perfluoroisobutyronitrile as an insulating medium comprises constructing a test platform for performing partial discharge using perfluoroisobutyronitrile as an insulating medium, and obtaining partial discharge parameters; controlling the test platform to perform partial discharge simulation on the insulating medium according to the partial discharge parameters to obtain a partial discharge pulse signal; extracting time domain and frequency domain data from the partial discharge pulse signal as partial discharge data, and constructing a phase-resolved spectrum according to the partial discharge data; extracting identification data from the phase-resolved spectrum, the identification data comprising an average discharge amount, a pulse count and a discharge pulse phase angle; and identifying the type of partial discharge defect of the insulating medium according to the identification data.

[0032] It can be seen from the above technical scheme that the present application has the following advantages: the local discharge defect method based on perfluoroisobutyronitrile as an insulating medium obtains a local discharge pulse signal for local discharge simulation using perfluoroisobutyronitrile as an insulating medium, extracts local discharge data in the time domain and frequency domain from the local discharge pulse signal and uses this data to form a phase-resolved spectrum, and identifies local discharge defects in environmentally friendly insulating gases such as perfluoroisobutyronitrile based on identification data obtained on the phase-resolved spectrum, thereby solving the existing technical problem of no local discharge defect identification for perfluoroisobutyronitrile C4F7N, an environmentally friendly gas.

[0033] The local discharge defect device based on perfluoroisobutyronitrile as the insulating medium cooperates with each other through platform construction and parameter acquisition module, discharge simulation module, data extraction module and defect identification module to determine the local discharge defect type of the insulating medium according to the identification data. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0035] Figure 1 This is a flowchart of the steps of the method for treating partial discharge defects based on perfluoroisobutyronitrile as an insulating medium described in an embodiment of the present application;

[0036] Figure 2This is a schematic diagram of a test platform in a partial discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in an embodiment of the present application;

[0037] Figure 3 It is a schematic diagram of the structure of the needle plate electrode in the local discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in the embodiment of the present application;

[0038] Figure 4 This is a schematic diagram of the structure of a spherical electrode in a local discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in an embodiment of the present application;

[0039] Figure 5 This is a schematic diagram of the structure of the first plate electrode in the local discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in an embodiment of the present application;

[0040] Figure 6 This is a schematic diagram of the structure of the second plate electrode in the local discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in an embodiment of the present application;

[0041] Figure 7 It is a phase-resolved spectrum diagram of particle defects in the local discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in the embodiment of the present application;

[0042] Figure 8 It is a phase-resolved spectrum diagram of a solid metal protrusion defect in a local discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in an embodiment of the present application;

[0043] Fig. 9 It is a phase-resolved spectrum diagram of contamination defects in the local discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in the embodiment of the present application;

[0044] Fig.10 It is a phase-resolved spectrum diagram of air gap defects in the local discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in the embodiment of the present application;

[0045] Fig.11 It is a schematic diagram of the framework of the partial discharge defect device based on perfluoroisobutyronitrile as the insulating medium described in the embodiment of the present application;

[0046] Fig.12 A schematic diagram of a terminal device described in an embodiment of the present application. DETAILED DESCRIPTION

[0047] In order to make the purpose, features, and advantages of the invention of this application more obvious and easy to understand, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the embodiments described below are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0048] In the description of the embodiments of the present application, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0049] In the embodiments of the present application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral one; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0050] The embodiments of the present application provide a method, device and equipment for local discharge defects based on perfluoroisobutyronitrile as an insulating medium, which solves the technical problem that there is no existing technical problem of local discharge defect identification of perfluoroisobutyronitrile C4F7N, an environmentally friendly gas.

[0051] Embodiment 1:

[0052] Figure 1 This is a flowchart of the steps of the method for treating partial discharge defects based on perfluoroisobutyronitrile as an insulating medium according to an embodiment of the present application. Figure 2 This is a schematic diagram of a test platform in a local discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in an embodiment of the present application.

[0053] like Figure 1 As shown, the embodiment of the present application provides a method for preventing partial discharge defects based on perfluoroisobutyronitrile as an insulating medium, comprising the following steps:

[0054] S1. Construct a test platform for partial discharge using perfluoroisobutyronitrile as the insulating medium, and obtain partial discharge parameters.

[0055] It should be noted that in step S1, the first step is to construct a test platform, and the second step is to obtain partial discharge parameters of partial discharge.

[0056] like Figure 2 As shown, in an embodiment of the present application, the test platform includes: an industrial frequency transformer 10, a protective resistor 20, a simulated gas chamber 30, a voltage-dividing capacitor 40, a coupling capacitor 50, a detection element 60 and an oscilloscope 70. The industrial frequency transformer 10 is also connected to the inductive voltage regulator 11. The first end of the industrial frequency transformer 10 is connected to the first end of the protective resistor 20, and the second end of the protective resistor 20 is respectively connected to the first end of the simulated gas chamber 30, the first end of the voltage-dividing capacitor 40 and the first end of the coupling capacitor 50. The second end of the coupling capacitor 50 is respectively connected to the first end of the detection element 60 and the oscilloscope 70. The second end of the detection element 60, the second end of the simulated gas chamber 30, the second end of the voltage-dividing capacitor 40 and the second end of the industrial frequency transformer 10 are grounded.

[0057] It should be noted that the detection element 60 can be a resistor. An air inlet for insulating medium gas is provided on the simulation air chamber 30. In this embodiment, a test electrode is installed in the simulation air chamber 30, and the test electrode is used to simulate the partial discharge phenomenon inside the electrical equipment. Among them, the test electrode can be a needle plate electrode, a spherical electrode, a first plate electrode or a second plate electrode.

[0058] Figure 3 This is a schematic diagram of the structure of the needle plate electrode in the local discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in the embodiment of the present application, Figure 4 This is a schematic diagram of the structure of a spherical electrode in a local discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in an embodiment of the present application, Figure 5 This is a schematic diagram of the structure of the first plate electrode in the local discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in an embodiment of the present application, Figure 6 This is a schematic diagram of the structure of the second plate electrode in the local discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in an embodiment of the present application.

[0059] like Figure 3 As shown, in the embodiment of the present application, the needle plate electrode includes a high voltage electrode and a ground electrode. The high voltage electrode is formed by a needle with a length of 17 mm, and the ground electrode is formed by a plate electrode with a diameter of 120 mm and a thickness of 10 mm. The spacing between the high voltage electrode and the ground electrode is 10 mm.

[0060] like Figure 4As shown, in an embodiment of the present application, the spherical electrode includes a shell in an unclosed spherical shape and a high-voltage electrode built into the shell. The high-voltage electrode is composed of a spherical electrode with a diameter of 50 mm, and the shell is composed of a metal material with a diameter of 100 mm, a shell thickness of 1.5 mm and a length of 90 mm at the opening. Among them, the distance between the bottom end of the high-voltage electrode and the inner wall of the shell is 25 mm. Several spherical elements with a diameter of 2 mm are placed in the inner wall of the shell. The spherical element can be a spherical component made of metal materials such as aluminum balls, iron balls, and copper balls. The spherical component can simulate particles because the surface of a normal defect-free device is smooth and free of metal particles.

[0061] like Figure 5 As shown, in an embodiment of the present application, the first plate electrode includes a high-voltage electrode and a ground electrode, and the spacing between the high-voltage electrode and the ground electrode is 25 mm. A columnar epoxy resin column is provided between the high-voltage electrode and the ground electrode, and a scrap strip is provided in the epoxy resin column. Among them, the scrap strip can be made of metal materials such as aluminum, iron, and copper. The length of the scrap strip can be 20 mm, and the width of the scrap strip can be 4 mm. The spacing between the scrap strip and the ground electrode is 2 mm. The diameter of the epoxy resin column is 80 mm. Both the high-voltage electrode and the ground electrode are composed of plate electrodes with a diameter of 120 mm and a thickness of 10 mm. The scrap strip can simulate contamination, because epoxy resin plays an insulating role in normal defect-free equipment, and the presence of contamination will reduce its insulation performance and increase the risk of equipment accidents.

[0062] like Figure 6 As shown, in an embodiment of the present application, the second plate electrode includes a high-voltage electrode and a ground electrode, and the spacing between the high-voltage electrode and the ground electrode is 52 mm. A columnar epoxy resin column is arranged between the high-voltage electrode and the ground electrode, and the bottom end of the epoxy resin column is closely arranged on the ground electrode. A gap is arranged between the top of the epoxy resin column and the high-voltage electrode. Among them, the diameter of the epoxy resin column is 80 mm, and the height of the epoxy resin column is 50 mm. Both the high-voltage electrode and the ground electrode are composed of plate electrodes with a diameter of 120 mm and a thickness of 10 mm. The gap is used to simulate the air gap, because if an air gap is generated in a metal depression in a normal defect-free device, its insulation performance will be reduced and the risk of equipment accidents will be increased.

[0063] In an embodiment of the present application, the local discharge parameters include the power frequency voltage of the power frequency transformer, the transformation ratio of the power frequency transformer, the capacity of the power frequency transformer, the secondary side rated current of the power frequency transformer, the resistance value of the protection resistor, the voltage divider ratio of the voltage divider capacitor, the high-frequency current component of the coupling capacitor, the impedance of the detection element, the sampling rate and the analog bandwidth.

[0064] It should be noted that the inductive voltage regulator 11 provides an AC voltage of 0~380V for the power frequency transformer; the power frequency transformer provides the required level of test voltage for the partial discharge test, the capacity of the power frequency transformer is 50kVA, the transformation ratio of the power frequency transformer is 0.4 / 100kV, the rated current of the secondary side of the power frequency transformer is 0.4A, and the power frequency voltage range of the power frequency transformer is 0~100kV; the AC high voltage signal generated by the power frequency transformer 10 is applied to the test electrode in the simulated gas chamber 30 through the protective resistor 20. The resistance of the protective resistor 20 is 10kΩ. The voltage dividing ratio of the voltage dividing capacitor 40 is 1:1000. The coupling capacitor 50 is used to extract the high-frequency current component in the partial discharge test. The impedance of the detection element is 50Ω, and the function of the detection element is to convert the current signal flowing through the detection impedance into a voltage signal; the coupling capacitor 50 and the detection element 60 are used to measure the pulse signal when the simulated gas chamber 30 has partial discharge, which is based on the pulse current method recommended by IEC60270. The oscilloscope 70 is used to collect and store the voltage signal transmitted by the detection element. In this embodiment, the model of the oscilloscope 70 can be Tektronix MDO3054, the test sampling rate can be 10 GS / s, and the analog bandwidth can be 1 GHz.

[0065] S2. Control the test platform to simulate partial discharge of the insulating medium according to the partial discharge parameters to obtain a partial discharge pulse signal.

[0066] It should be noted that in step S2, the test platform constructed according to step S1 performs partial discharge simulation on the insulating medium to obtain a sequence of continuous partial discharge pulse signals. In this embodiment, the partial discharge signal includes statistical characteristic parameters such as discharge amount, discharge phase, discharge frequency, and discharge amplitude, as well as waveform characteristic parameters such as duration, pulse width, and rise time of the partial discharge waveform. Among them, the local time domain parameters include the duration, pulse width, and rise time of the partial discharge waveform, and the frequency domain parameters include the discharge phase, discharge frequency, and discharge amplitude. According to the partial discharge parameters, the pulse current method is used to control the test platform to simulate partial discharge of the insulating medium. The partial discharge pulse signal can be measured by an oscilloscope based on the pulse current method of IEC60270.

[0067] S3. Extract time domain and frequency domain data from the local discharge pulse signal as local discharge data, and construct a phase-resolved spectrum based on the local discharge data; extract identification data from the phase-resolved spectrum, and the identification data includes an average discharge amount, a pulse count, and a discharge pulse phase angle.

[0068] It should be noted that in step S3, continuous time domain data and frequency domain data are extracted from the partial discharge pulse signal obtained in step S2 as partial discharge data. The partial discharge data at least includes the discharge phase and the corresponding duration, pulse width, rise time, discharge amplitude, etc. In this embodiment, the partial discharge data is plotted into a phase-resolved spectrum with the discharge phase as the horizontal coordinate and the discharge amplitude as the vertical coordinate. After that, the identification data such as the average discharge amount, pulse count and discharge pulse phase angle are directly extracted from the phase-resolved spectrum to provide data for the subsequent identification of partial discharge defects.

[0069] S4. Identify the partial discharge defect type of the insulating medium according to the identification data.

[0070] It should be noted that in step S4, the identification data obtained in step S3 is used to determine which type of partial discharge defect the insulating medium belongs to. In this embodiment, the partial discharge defect types include particle defects, solid metal protrusion defects, contamination defects and air gap defects.

[0071] The present application provides a method for detecting partial discharge defects based on perfluoroisobutyronitrile as an insulating medium, including constructing a test platform for partial discharge using perfluoroisobutyronitrile as an insulating medium, and obtaining partial discharge parameters; controlling the test platform to simulate partial discharge on the insulating medium according to the partial discharge parameters to obtain a partial discharge pulse signal; extracting time domain and frequency domain data from the partial discharge pulse signal as partial discharge data, and constructing a phase-resolved spectrum according to the partial discharge data; extracting identification data from the phase-resolved spectrum, the identification data including average discharge amount, pulse count and discharge pulse phase angle; identifying the type of partial discharge defect of the insulating medium according to the identification data. The method for detecting partial discharge defects based on perfluoroisobutyronitrile as an insulating medium obtains a partial discharge pulse signal for partial discharge simulation using perfluoroisobutyronitrile as an insulating medium, extracts partial discharge data in the time domain and frequency domain from the partial discharge pulse signal and constructs a phase-resolved spectrum with this data, and identifies partial discharge defects in environmentally friendly insulating gases such as perfluoroisobutyronitrile according to the identification data obtained on the phase-resolved spectrum, thereby solving the technical problem that there is no local discharge defect identification for the environmentally friendly gas perfluoroisobutyronitrile C4F7N.

[0072] It should be noted that the partial discharge defect method based on perfluoroisobutyronitrile as an insulating medium can also be applied to the identification of partial discharge defects of electrical equipment and electrical equipment in actual engineering. The identification results of the partial discharge defect method based on perfluoroisobutyronitrile as an insulating medium will help the environmentally friendly gas perfluoroisobutyronitrile C4F7N to be used as an insulating medium in power equipment, and the identification results can be used as reference data to facilitate the asset management, fault identification and maintenance of the power equipment.

[0073] Figure 7This is a phase-resolved spectrum diagram of particle defects in the local discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in the embodiment of the present application, Figure 8 This is a phase-resolved spectrum diagram of a solid metal protrusion defect in a local discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in an embodiment of the present application, Fig. 9 This is a phase-resolved spectrum diagram of a contamination defect in a local discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in an embodiment of the present application, Fig.10 This is a phase-resolved spectrum diagram of air gap defects in the local discharge defect method based on perfluoroisobutyronitrile as an insulating medium described in an embodiment of the present application.

[0074] like Figures 7 to 10 As shown, in one embodiment of the present application, identifying the type of partial discharge defect of the insulating medium according to the identification data includes:

[0075] If the average discharge amount is a first charge threshold, the pulse count is a first count threshold, and the discharge pulse phase angle is a first phase threshold, then the local discharge defect type is a particle defect;

[0076] If the average discharge amount is the second charge threshold, the pulse count is the second count threshold, and the discharge pulse phase angle is the second phase threshold, then the local discharge defect type is a solid metal protrusion defect;

[0077] If the average discharge amount is the third charge threshold, the pulse count is the third count threshold, and the discharge pulse phase angle is the third phase threshold, the partial discharge defect type is a contamination defect;

[0078] If the average discharge amount is a fourth charge threshold, the pulse count is a fourth count threshold, and the discharge pulse phase angle is a fourth phase threshold, the local discharge defect type is an air gap defect.

[0079] It should be noted that the first charge threshold is 459mV, the first count threshold is 183N / s, and the first phase threshold is 0°~360°; and / or, the second charge threshold is 32mV, the second count threshold is 42N / s, and the second phase threshold is 61°~102°; and / or, the third charge threshold is 42mV, the third count threshold is 504N / s, and the third phase threshold is 46°~130° and 254°~302°; and / or, the fourth charge threshold is 244mV, the fourth count threshold is 187N / s, and the fourth phase threshold is 16°~118° and 182°~254°. In this embodiment, the local discharge defect method based on perfluoroisobutyronitrile as an insulating medium can judge different defect types according to the average discharge amount, pulse count and discharge pulse phase angle distribution of different defect types.

[0080] Embodiment 2:

[0081] Fig.11 This is a schematic diagram of the framework of a local discharge defect device based on perfluoroisobutyronitrile as an insulating medium as described in an embodiment of the present application.

[0082] like Fig.11 As shown, the embodiment of the present application provides a partial discharge defect device based on perfluoroisobutyronitrile as an insulating medium, including a platform construction and parameter acquisition module 100, a discharge simulation module 200, a data extraction module 300 and a defect identification module 400;

[0083] The platform construction and parameter acquisition module 100 is used to construct a test platform for partial discharge using perfluoroisobutyronitrile as an insulating medium, and to obtain partial discharge parameters;

[0084] The discharge simulation module 200 is used to control the test platform to perform partial discharge simulation on the insulating medium according to the partial discharge parameters to obtain a partial discharge pulse signal;

[0085] The data extraction module 300 is used to extract time domain and frequency domain data from the partial discharge pulse signal as partial discharge data, and construct a phase-resolved spectrum according to the partial discharge data; extract identification data from the phase-resolved spectrum, and the identification data includes an average discharge amount, a pulse count, and a discharge pulse phase angle;

[0086] The defect identification module 400 is used to identify the type of partial discharge defect of the insulating medium according to the identification data.

[0087] It should be noted that the content of the module in the partial discharge defect device based on perfluoroisobutyronitrile as the insulating medium corresponds to the step content of the partial discharge defect method based on perfluoroisobutyronitrile as the insulating medium, and the step content of the partial discharge defect method based on perfluoroisobutyronitrile as the insulating medium has been described in the first embodiment, and the content of the module in the partial discharge defect device based on perfluoroisobutyronitrile as the insulating medium will not be repeated in this embodiment. The partial discharge defect device based on perfluoroisobutyronitrile as the insulating medium cooperates with each other through the platform construction and parameter acquisition module, the discharge simulation module, the data extraction module and the defect identification module to realize the judgment of the partial discharge defect type of the insulating medium according to the identification data.

[0088] In one embodiment of the present application, the defect identification module 400 is also used to determine that the local discharge defect type is a particle defect based on the average discharge amount being a first charge threshold, the pulse count being a first count threshold, and the discharge pulse phase angle being a first phase threshold; or that the local discharge defect type is a solid metal protrusion defect based on the average discharge amount being a second charge threshold, the pulse count being a second count threshold, and the discharge pulse phase angle being a second phase threshold; or that the local discharge defect type is a contamination defect based on the average discharge amount being a third charge threshold, the pulse count being a third count threshold, and the discharge pulse phase angle being a third phase threshold; or that the local discharge defect type is an air gap defect based on the average discharge amount being a fourth charge threshold, the pulse count being a fourth count threshold, and the discharge pulse phase angle being a fourth phase threshold.

[0089] In one embodiment of the present application, the first charge threshold is 459mV, the first count threshold is 183N / s, and the first phase threshold is 0°~360°; and / or, the second charge threshold is 32mV, the second count threshold is 42N / s, and the second phase threshold is 61°~102°; and / or, the third charge threshold is 42mV, the third count threshold is 504N / s, and the third phase threshold is 46°~130° and 254°~302°; and / or, the fourth charge threshold is 244mV, the fourth count threshold is 187N / s, and the fourth phase threshold is 16°~118° and 182°~254°.

[0090] In one embodiment of the present application, the test platform includes: an industrial frequency transformer, a protective resistor, a simulated gas chamber, a voltage-dividing capacitor, a coupling capacitor, a detection element and an oscilloscope, an inductive voltage regulator is arranged on the industrial frequency transformer, a first end of the industrial frequency transformer is connected to a first end of the protective resistor, a second end of the protective resistor is respectively connected to a first end of the simulated gas chamber, a first end of the voltage-dividing capacitor and a first end of the coupling capacitor, a second end of the coupling capacitor is respectively connected to a first end of the detection element and the oscilloscope, a second end of the detection element, a second end of the simulated gas chamber, a second end of the voltage-dividing capacitor and a second end of the industrial frequency transformer are grounded; and / or, partial discharge parameters include the industrial frequency voltage of the industrial frequency transformer, the transformation ratio of the industrial frequency transformer, the capacity of the industrial frequency transformer, the rated current of the secondary side of the industrial frequency transformer, the resistance value of the protective resistor, the voltage-dividing ratio of the voltage-dividing capacitor, the high-frequency current component of the coupling capacitor, the impedance of the detection element, the sampling rate and the analog bandwidth.

[0091] Embodiment three:

[0092] Fig.12 A schematic diagram of a terminal device described in an embodiment of the present application.

[0093] like Fig.12 As shown, an embodiment of the present application provides a terminal device, including a processor and a memory;

[0094] A memory, used for storing program codes and transmitting the program codes to a processor;

[0095] A processor is used to execute the above-mentioned partial discharge defect method based on perfluoroisobutyronitrile as an insulating medium according to instructions in the program code.

[0096] It should be noted that the processor is used to execute the steps in the above-mentioned embodiment of a method for treating partial discharge defects based on perfluoroisobutyronitrile as an insulating medium according to the instructions in the program code. Alternatively, the processor implements the functions of each module / unit in the above-mentioned system / device embodiments when executing the computer program.

[0097] Exemplarily, the computer program may be divided into one or more modules / units, one or more modules / units are stored in a memory and executed by a processor to complete the present application. One or more modules / units may be a series of computer program instruction segments capable of completing a specific function, and the instruction segments are used to describe the execution process of the computer program in a terminal device.

[0098] The terminal device may be a computing device such as a desktop computer, a notebook, a PDA, or a cloud server. The terminal device may include, but is not limited to, a processor and a memory. Those skilled in the art will appreciate that this does not constitute a limitation on the terminal device, and may include more or fewer components than shown in the figure, or a combination of certain components, or different components. For example, the terminal device may also include input and output devices, network access devices, buses, etc.

[0099] The processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (dSIC), field-programmable gate arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor may be a microprocessor or any conventional processor, etc.

[0100] The memory may be an internal storage unit of the terminal device, such as a hard disk or memory of the terminal device. The memory may also be an external storage device of the terminal device, such as a plug-in hard disk, a smart memory card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the terminal device. Furthermore, the memory may include both an internal storage unit of the terminal device and an external storage device. The memory is used to store computer programs and other programs and data required by the terminal device. The memory may also be used to temporarily store data that has been output or is to be output.

[0101] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0102] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0103] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0104] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0105] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., various media that can store program codes.

[0106] As described above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application 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 application.

Claims

1. A method for partial discharge defects based on perfluoroisobutyronitrile as an insulating medium, characterized in that: The following steps are involved: Construct a test platform for partial discharge using perfluoroisobutyronitrile as the insulating medium and obtain partial discharge parameters; Controlling the test platform to perform partial discharge simulation on the insulating medium according to the partial discharge parameters to obtain a partial discharge pulse signal; Extracting time domain and frequency domain data from the partial discharge pulse signal as partial discharge data, and constructing a phase-resolved spectrum according to the partial discharge data; extracting identification data from the phase-resolved spectrum, wherein the identification data includes an average discharge amount, a pulse count, and a discharge pulse phase angle; The partial discharge defect type of the insulating medium is identified according to the identification data.

2. The local discharge defect method based on perfluoroisobutyronitrile as an insulating medium according to claim 1, characterized in that: Identifying the partial discharge defect type of the insulating medium according to the identification data includes: If the average discharge amount is a first charge threshold, the pulse count is a first count threshold, and the discharge pulse phase angle is a first phase threshold, then the local discharge defect type is a particle defect; If the average discharge amount is the second charge threshold, the pulse count is the second count threshold, and the discharge pulse phase angle is the second phase threshold, then the local discharge defect type is a solid metal protrusion defect; If the average discharge amount is a third charge threshold, the pulse count is a third count threshold, and the discharge pulse phase angle is a third phase threshold, then the local discharge defect type is a contamination defect; If the average discharge amount is a fourth charge threshold, the pulse count is a fourth count threshold, and the discharge pulse phase angle is a fourth phase threshold, then the local discharge defect type is an air gap defect.

3. The local discharge defect method based on perfluoroisobutyronitrile as an insulating medium according to claim 2, characterized in that: The first charge threshold is 459mV, the first count threshold is 183N / s, and the first phase threshold is 0°~360°; and / or, the second charge threshold is 32mV, the second count threshold is 42N / s, and the second phase threshold is 61°~102°; and / or, the third charge threshold is 42mV, the third count threshold is 504N / s, and the third phase threshold is 46°~130° and 254°~302°; and / or, the fourth charge threshold is 244mV, the fourth count threshold is 187N / s, and the fourth phase threshold is 16°~118° and 182°~254°.

4. The local discharge defect method based on perfluoroisobutyronitrile as an insulating medium according to claim 1, characterized in that: The test platform includes: an industrial frequency transformer, a protective resistor, a simulated air chamber, a voltage-dividing capacitor, a coupling capacitor, a detection element and an oscilloscope. The industrial frequency transformer is also connected to an inductive voltage regulator. The first end of the industrial frequency transformer is connected to the first end of the protective resistor. The second end of the protective resistor is respectively connected to the first end of the simulated air chamber, the first end of the voltage-dividing capacitor and the first end of the coupling capacitor. The second end of the coupling capacitor is respectively connected to the first end of the detection element and the oscilloscope. The second end of the detection element, the second end of the simulated air chamber, the second end of the voltage-dividing capacitor and the second end of the industrial frequency transformer are grounded.

5. The method for partial discharge defects based on perfluoroisobutyronitrile as an insulating medium according to claim 4, characterized in that: The partial discharge parameters include the power frequency voltage of the power frequency transformer, the transformation ratio of the power frequency transformer, the capacity of the power frequency transformer, the secondary side rated current of the power frequency transformer, the resistance value of the protection resistor, the voltage divider ratio of the voltage divider capacitor, the high-frequency current component of the coupling capacitor, the impedance of the detection element, the sampling rate and the analog bandwidth.

6. A partial discharge defect device based on perfluoroisobutyronitrile as an insulating medium, characterized in that: It includes platform construction and parameter acquisition module, discharge simulation module, data extraction module and defect identification module; The platform construction and parameter acquisition module is used to construct a test platform for partial discharge using perfluoroisobutyronitrile as an insulating medium, and to obtain partial discharge parameters; The discharge simulation module is used to control the test platform to perform partial discharge simulation on the insulating medium according to the partial discharge parameters to obtain a partial discharge pulse signal; The data extraction module is used to extract time domain and frequency domain data from the partial discharge pulse signal as partial discharge data, and construct a phase-resolved spectrum according to the partial discharge data; extract identification data from the phase-resolved spectrum, and the identification data includes an average discharge amount, a pulse count and a discharge pulse phase angle; The defect identification module is used to identify the partial discharge defect type of the insulating medium according to the identification data.

7. The partial discharge defect device based on perfluoroisobutyronitrile as the insulating medium according to claim 6, characterized in that: The defect identification module is also used to determine that the local discharge defect type is a particle defect based on the average discharge amount being a first charge threshold, the pulse count being a first count threshold, and the discharge pulse phase angle being a first phase threshold; or that the local discharge defect type is a solid metal protrusion defect based on the average discharge amount being a second charge threshold, the pulse count being a second count threshold, and the discharge pulse phase angle being a second phase threshold; or that the local discharge defect type is a contamination defect based on the average discharge amount being a third charge threshold, the pulse count being a third count threshold, and the discharge pulse phase angle being a third phase threshold; or that the local discharge defect type is an air gap defect based on the average discharge amount being a fourth charge threshold, the pulse count being a fourth count threshold, and the discharge pulse phase angle being a fourth phase threshold.

8. The partial discharge defect device based on perfluoroisobutyronitrile as the insulating medium according to claim 7, characterized in that: The first charge threshold is 459mV, the first count threshold is 183N / s, and the first phase threshold is 0°~360°; and / or, the second charge threshold is 32mV, the second count threshold is 42N / s, and the second phase threshold is 61°~102°; and / or, the third charge threshold is 42mV, the third count threshold is 504N / s, and the third phase threshold is 46°~130° and 254°~302°; and / or, the fourth charge threshold is 244mV, the fourth count threshold is 187N / s, and the fourth phase threshold is 16°~118° and 182°~254°.

9. The partial discharge defect device based on perfluoroisobutyronitrile as an insulating medium according to claim 6, characterized in that: The test platform includes: an industrial frequency transformer, a protection resistor, a simulated gas chamber, a voltage-dividing capacitor, a coupling capacitor, a detection element and an oscilloscope, wherein the industrial frequency transformer is also connected to an inductive voltage regulator, the first end of the industrial frequency transformer is connected to the first end of the protection resistor, the second end of the protection resistor is respectively connected to the first end of the simulated gas chamber, the first end of the voltage-dividing capacitor and the first end of the coupling capacitor, the second end of the coupling capacitor is respectively connected to the first end of the detection element and the oscilloscope, the second end of the detection element, the second end of the simulated gas chamber, the second end of the voltage-dividing capacitor and the second end of the industrial frequency transformer are grounded; and / or, the partial discharge parameters include the industrial frequency voltage of the industrial frequency transformer, the transformation ratio of the industrial frequency transformer, the capacity of the industrial frequency transformer, the secondary side rated current of the industrial frequency transformer, the resistance value of the protection resistor, the voltage-dividing ratio of the voltage-dividing capacitor, the high-frequency current component of the coupling capacitor, the impedance of the detection element, the sampling rate and the simulation bandwidth.

10. A terminal device, characterized in that: including a processor and a memory; The memory is used to store program codes and transmit the program codes to the processor; The processor is used to execute the local discharge defect method based on perfluoroisobutyronitrile as an insulating medium as described in any one of claims 1 to 5 according to the instructions in the program code.

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