A partial discharge ultrasonic and super high frequency integrated sensor performance test method

Abstract

The present application relates to power equipment insulation detection technology, and particularly relates to a partial discharge ultrasonic and ultra-high frequency integrated sensor performance test method, which is used for testing the following discharge insulation defects, respectively: corona discharge defects; air gap discharge defects; surface discharge defects; free particle discharge defects; and suspended discharge defects; the test method comprises: testing the breakdown voltage under different discharge insulation defects; a partial discharge ultra-high frequency signal sensing performance test method, a partial discharge ultrasonic signal sensing performance test method, and a partial discharge ultrasonic signal and ultra-high frequency signal simultaneous sensing performance test method. By using the method, the sensing performance of the partial discharge ultrasonic and ultra-high frequency integrated sensor on the partial discharge signal of the power equipment can be conveniently and quickly tested in the laboratory and the power field.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of power equipment insulation detection, and particularly relates to a partial discharge ultrasonic and ultra-high frequency integrated sensor performance test method. BACKGROUND

[0002] High-voltage power equipment is widely used in power systems, but a series of unavoidable discharge insulation defects will be generated in the process of manufacturing, transportation, installation and operation of such equipment, and long-term discharge will probably induce breakdown discharge accidents, so effective discharge insulation defect detection of such equipment is the top priority to ensure the safe operation of power equipment. The existing discharge insulation defect detection means of power equipment mainly detects a series of characteristic signals generated by discharge insulation defects by using corresponding ultrasonic sensors, UHF antenna sensors, high-frequency CT sensors and the like, but the currently used sensors have the problems of single function and low flexibility. In view of these problems, the ultrasonic characteristic signals and high-frequency electromagnetic wave characteristic signals commonly used for discharge insulation defect diagnosis can be fused in a single sensor, that is, a single sensor (integrated sensor) is used to simultaneously sense the ultrasonic characteristic signals and the high-frequency electromagnetic wave characteristic signals, and the signals are output from one output port, so that the problem of single function of the sensor can be solved, the complexity of the partial discharge ultrasonic and ultra-high frequency combined detection system is greatly reduced, the problem of low flexibility of the sensor and the inability to conform to the structure of some arc-shaped power equipment can be solved by using flexible materials, and convenient and 100% reliable judgment of discharge insulation defects can be realized by comparing the time difference of the high-frequency electromagnetic wave and ultrasonic wave signals output by the single sensor. At present, the performance test method of the discharge insulation defect sensing sensor is only for single-function sensors (such as ultrasonic sensors and UHF antenna sensors), and these test methods cannot be used for integrated sensor performance test due to the difference in sampling rate and sensing principle, so a new test method needs to be proposed in order to obtain the performance parameters of the integrated sensor. SUMMARY

[0003] In view of the problems in the background art, the application provides a partial discharge ultrasonic and ultra-high frequency integrated sensor performance test method.

[0004] To solve the above technical problems, the application adopts the following technical scheme: a partial discharge ultrasonic and ultra-high frequency integrated sensor performance test method, which tests the following discharge insulation defects: ① corona discharge defect; ② air gap discharge defect; ③ surface discharge defect; ④ free particle discharge defect; and ⑤ suspension discharge defect. The test method comprises: testing the breakdown voltage under different discharge insulation defects; a partial discharge ultra-high frequency signal sensing performance test method, a partial discharge ultrasonic signal sensing performance test method, and a partial discharge ultrasonic signal and ultra-high frequency signal simultaneous sensing performance test method.

[0005] In the above-mentioned performance testing method for the integrated ultrasonic and ultra-high frequency partial discharge sensor, the partial discharge ultra-high frequency signal sensing performance testing method is based on a partial discharge ultra-high frequency signal sensing performance testing circuit. This circuit includes: a discharge insulation defect model shell, a detection impedance, a comparison ultra-high frequency sensor, an integrated sensor, a bandpass filter, and an oscilloscope. The discharge insulation defect model shell is made of non-metallic material. The testing method includes the following steps:

[0006] Step 01: First, attach the integrated sensor to the surface of the discharge insulation defect model shell using ultrasonic coupling agent and insulating tape. In contrast, place the UHF sensor on the side of the discharge insulation defect model shell, or use a flexible UHF sensor to attach it to the surface of the discharge insulation defect model shell using insulating tape.

[0007] Step 02: After checking the circuit, apply pressure to the experimental platform, not exceeding the breakdown voltage, and stabilize the voltage for a certain period of time. When the discharge insulation defect has not shown a breakdown phenomenon, connect the detection impedance to the high-performance oscilloscope and record the discharge quantity at this voltage. Connect the UHF sensor for comparison and the integrated sensor to the high-performance oscilloscope and adjust the sampling rate to meet the requirements of UHF spectrum analysis. When the UHF sensor channel for comparison and the integrated sensor channel show pulse signals at the same time, record the data.

[0008] Step 03: Perform Fourier transform on the collected data and compare the signals collected by the integrated sensor with those collected by the UHF sensor. If the energy distribution frequency bands of the signals collected by the integrated sensor and the UHF sensor are similar, then the integrated sensor can effectively sense the UHF signals generated by partial discharge.

[0009] Step 04: After testing one type of discharge insulation defect, change the discharge insulation defect and repeat steps 01-02 to test the sensing performance of the integrated sensor for partial discharge UHF signals under different discharge insulation defects.

[0010] In the above-mentioned performance testing method for the integrated ultrasonic and ultra-high frequency partial discharge sensor, the partial discharge ultrasonic signal sensing performance testing method is based on a partial discharge ultrasonic signal sensing performance testing circuit. This circuit includes: a discharge insulation defect model shell, a detection impedance, a metal layer, an integrated sensor, a bandpass filter, a high-performance oscilloscope, a comparison ultrasonic sensor, and an ultrasonic amplifier. The discharge insulation defect model shell is made of non-metallic material. The testing method includes the following steps:

[0011] Step 11, paste the metal layer to the surface of the discharge insulation defect model shell, and ground the metal layer for simulating the metal shell of the power equipment; the integrated sensor and the contrast ultrasonic sensor are pasted to the outer surface of the metal layer using ultrasonic coupling agent and insulating tape, wherein a metal layer is used to seal the outside of the integrated sensor and avoid the contact between the metal layer and the surface electrode of the integrated sensor;

[0012] Step 12, connect the integrated sensor and the contrast ultrasonic sensor to the ultrasonic amplifier, and then connect to the high-performance oscilloscope, and adjust the sampling rate of the high-performance oscilloscope to meet the ultrasonic spectrum analysis;

[0013] Step 13, knock the discharge insulation defect model shell before pressurization, and observe whether there is a knocking pulse signal output on the integrated sensor channel and the contrast ultrasonic sensor channel of the high-performance oscilloscope to confirm that the line connection is normal;

[0014] Step 14, disconnect the equipment connected to the high-performance oscilloscope before pressurization, pressurize the experimental platform, and do not exceed the breakdown pressure, and stabilize the voltage for a certain period of time; if the discharge insulation defect does not appear breakdown phenomenon, connect the detection impedance to the high-performance oscilloscope, record the discharge amount under the voltage; connect the contrast ultrasonic sensor with the ultrasonic amplifier and the integrated sensor with the same model ultrasonic amplifier to the high-performance oscilloscope, adjust the sampling rate and the amplification multiple of the ultrasonic amplifier to meet the requirements, and record the data when the pulse signals appear on the contrast ultrasonic sensor channel and the integrated sensor channel at the same time;

[0015] Step 15, Fourier transform the collected data, and compare and analyze the signals collected by the integrated sensor and the contrast ultrasonic sensor, if the energy distribution frequency bands of the signals collected by the integrated sensor and the contrast ultrasonic sensor are similar, the integrated sensor can effectively perceive the ultrasonic signals generated by the partial discharge;

[0016] Step 16, after testing one kind of discharge insulation defect, replace the discharge insulation defect, and repeat steps 11-15 to test the sensing performance of the integrated sensor on the partial discharge ultrasonic signal under different discharge insulation defects.

[0017] In the above partial discharge ultrasonic and ultrahigh frequency integrated sensor performance test method, the partial discharge ultrasonic and ultrahigh frequency signal simultaneous sensing performance test method is based on a partial discharge ultrasonic and ultrahigh frequency signal simultaneous sensing performance test circuit, and the test circuit comprises: a discharge insulation defect model shell, a detection impedance, a contrast ultrahigh frequency sensor, a metal layer, an integrated sensor, a band-pass filter, a high-performance oscilloscope, a contrast ultrasonic sensor and an ultrasonic amplifier; the discharge insulation defect model shell is made of non-metallic material; the test method comprises the following steps:

[0018] Step 21, remove a part of the metal layer pasted on the discharge insulation defect model shell, so that one part of the integrated sensor is in contact with the discharge insulation defect model shell and the other part is in contact with the metal layer, so that the integrated sensor senses the ultra-high frequency signal generated by the partial discharge;

[0019] Step 22, place the contrast ultrasonic sensor and the integrated sensor on the surface of the metal layer, and seal the outside of the integrated sensor with the metal layer, for simulating the integrated sensor built-in power equipment, wherein the metal layer avoids contact with the surface electrode of the integrated sensor, the integrated sensor and the contrast ultrasonic sensor are connected to the ultrasonic amplifier, and are connected to the high-performance oscilloscope;

[0020] Step 23, knock the discharge insulation defect model shell before pressurization, and observe whether there is a knocking pulse signal output on the high-performance oscilloscope channel of the integrated sensor and the contrast ultrasonic sensor channel, to confirm that the line connection is normal;

[0021] Step 24, pressurize the experimental platform, not more than the breakdown pressure, and stabilize at the voltage for a certain period of time, and the discharge insulation defect does not appear breakdown phenomenon, connect the detection impedance to the high-performance oscilloscope, record the discharge amount at the voltage, then connect the contrast ultrasonic sensor connected with the ultrasonic amplifier, the contrast ultrasonic sensor connected with the ultrasonic amplifier and the integrated sensor connected with the same type ultrasonic amplifier to the high-performance oscilloscope respectively, and adjust the sampling rate of the high-performance oscilloscope to collect the partial discharge ultra-high frequency signal sensed by the contrast ultrasonic sensor, when the contrast ultrasonic sensor channel, the contrast ultrasonic sensor channel and the integrated sensor channel appear pulse signals at the same time, collect the data of the three channels;

[0022] Step 25, analyze the collected data by time delay method, and the time difference between the time domain waveform of the contrast ultrasonic signal and the time domain waveform of the contrast ultrasonic signal in the collected data waveform is recorded as time difference 1, which is the same as the time of ultrasonic wave propagation from the partial discharge source to the contrast ultrasonic sensor in the medium; if the pulse signal time domain waveform detected by the integrated sensor exists time difference, record it as time difference 2, and the time difference 2 is the same as the time difference 1, then the integrated sensor senses the ultrasonic signal and the ultra-high frequency signal generated by the partial discharge at the same time;

[0023] Step 26, after testing one kind of discharge insulation defect, replace the discharge insulation defect, repeat steps 21-25, and test the performance of the integrated sensor in sensing the partial discharge ultrasonic signal and the ultra-high frequency signal at the same time under different discharge insulation defects.

[0024] Compared with the prior art, the method can be used for integrated sensing performance test, and can conveniently and quickly test the sensing performance of the ultrasonic and UHF integrated sensor of the power equipment partial discharge signal in a laboratory and a power site. BRIEF DESCRIPTION OF DRAWINGS

[0025] Fig. 1(a) is a corona discharge insulation defect model used for testing the performance of the power equipment partial discharge ultrasonic and UHF integrated sensor according to the embodiment of the present application;

[0026] Fig. 1(b) is a gas gap discharge insulation defect model used for testing the performance of the power equipment partial discharge ultrasonic and UHF integrated sensor according to the embodiment of the present application;

[0027] Fig. 1(c) is a surface discharge insulation defect model used for testing the performance of the power equipment partial discharge ultrasonic and UHF integrated sensor according to the embodiment of the present application;

[0028] Fig. 1(d) is a free particle discharge insulation defect model used for testing the performance of the power equipment partial discharge ultrasonic and UHF integrated sensor according to the embodiment of the present application;

[0029] Fig. 1(e) is a suspension discharge insulation defect model used for testing the performance of the power equipment partial discharge ultrasonic and UHF integrated sensor according to the embodiment of the present application;

[0030] Figure 2 Fig. 2 is an experimental circuit for testing the sensing performance of the power equipment partial discharge ultrasonic and UHF integrated sensor on the partial discharge UHF signal according to the embodiment of the present application;

[0031] Figure 3 Fig. 3 is a flowchart of the experimental process for testing the sensing performance of the power equipment partial discharge ultrasonic and UHF integrated sensor on the partial discharge UHF signal according to the embodiment of the present application;

[0032] Figure 4 Fig. 4 is an experimental circuit for testing the sensing performance of the power equipment partial discharge ultrasonic and UHF integrated sensor on the partial discharge ultrasonic signal according to the embodiment of the present application;

[0033] Figure 5 Fig. 5 is a flowchart of the experimental process for testing the sensing performance of the power equipment partial discharge ultrasonic and UHF integrated sensor on the partial discharge ultrasonic signal according to the embodiment of the present application;

[0034] Figure 6 Fig. 6 is an experimental circuit for testing the simultaneous sensing performance of the power equipment partial discharge ultrasonic and UHF integrated sensor on the partial discharge ultrasonic and UHF signals according to the embodiment of the present application;

[0035] Figure 7A flow chart of a performance test experiment of the power equipment partial discharge ultrasonic and ultra-high frequency integrated sensor of the embodiment of the present application for simultaneously sensing partial discharge ultrasonic and ultra-high frequency signals;

[0036] Wherein, 1-discharge insulation defect model shell, 2-high voltage electrode, 3-ground electrode, 4-discharge insulation defect, 5-insulating material, 6-free particle, 7-metal needle tip, 8-detection impedance, 9-contrast ultra-high frequency sensor, 10-metal layer, 11-integrated sensor, 12-band pass filter, 13-high performance oscilloscope, 14-contrast ultrasonic sensor, 15-ultrasonic amplifier. DETAILED DESCRIPTION

[0037] The technical solutions in the embodiments of the present application will be clearly and completely described below with the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0038] It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0039] The present application will be further described below with specific embodiments, but is not limited to the present application.

[0040] The performance test method of the ultrasonic and ultra-high frequency integrated sensor for partial discharge detection of the power equipment in the embodiment can test the ultra-high frequency sensing performance and the ultrasonic sensing performance of the integrated sensor respectively under the condition of meeting the sampling rate of the frequency domain analysis and the integrated sensor sensing principle, or test the performance of the integrated sensor for simultaneously sensing ultrasonic signals and ultra-high frequency signals from the time domain aspect on the premise of sacrificing the sampling rate.

[0041] The embodiment is realized by the following technical solutions, a performance test method of a partial discharge ultrasonic and ultra-high frequency integrated sensor, comprising: a partial discharge ultra-high frequency signal sensing performance test method; a partial discharge ultrasonic signal sensing performance test method; and a partial discharge ultrasonic and ultra-high frequency signal simultaneous sensing performance test method.

[0042] The partial discharge ultra-high frequency signal sensing performance test is realized based on a partial discharge ultra-high frequency signal sensing performance test circuit; the partial discharge ultrasonic signal sensing performance test method is realized based on a partial discharge ultrasonic signal sensing performance test circuit; and the partial discharge ultrasonic and ultra-high frequency signal simultaneous sensing performance test method is realized based on a partial discharge ultrasonic and ultra-high frequency signal simultaneous sensing performance test circuit.

[0043] All discharge insulation defect models in the method are shown in Fig. 1(a), Fig. 1(b), Fig. 1(c), Fig. 1(d), and Fig. 1(e), and different discharge insulation defects 4 are arranged inside the discharge insulation defect model shell 1 for simulating typical discharge insulation defects in power equipment.

[0044] Five typical discharge insulation defects are provided in the embodiment, as shown in Fig. 1(a), ① corona discharge defect is composed of a needle electrode on the high-voltage electrode 2 and a ground electrode 3; as shown in Fig. 1(b), ② air gap discharge defect is composed of a plate electrode on the high-voltage electrode 2, a ground electrode 3, and insulating material 5 containing bubbles; as shown in Fig. 1(c), ③ surface discharge defect is composed of a rod electrode on the high-voltage electrode 2, a ground electrode 3, and insulating material 5; as shown in Fig. 1(d), ④ free particle discharge defect is composed of a plate electrode on the high-voltage electrode 2, a ground electrode 3, and a free particle 6 placed on the ground electrode 3; and as shown in Fig. 1(e), ⑤ suspension discharge defect is composed of a needle electrode on the high-voltage electrode 2, insulating material 5, a metal needle tip 7 placed on the insulating material 5, and a ground electrode 3.

[0045] Firstly, the breakdown voltage under different discharge insulation defects is tested in the embodiment to ensure the safety of the experimental instruments.

[0046] The power equipment partial discharge ultrasonic and UHF integrated sensor signal sensing performance test experimental circuit of the embodiment is shown in Fig. 1(f) and includes: a discharge insulation defect model shell 1, the side of the shell needs to be a non-metallic material such as organic glass, a detection impedance 8, a comparative UHF sensor 9, an integrated sensor 11, a band-pass filter 12, and a high-performance oscilloscope 13. Figure 2

[0047] I. The power equipment partial discharge ultrasonic and UHF integrated sensor signal sensing performance test method is shown in Fig. 1(g) and includes: Figure 3

[0048] 1) Firstly, the integrated sensor 11 is pasted to the surface of the discharge insulation defect model shell 1 using ultrasonic coupling agent and insulating tape, the comparative UHF sensor 9 is placed on the side of the discharge insulation defect model shell 1, or the flexible UHF sensor is pasted to the surface of the discharge insulation defect model shell 1 using insulating tape;

[0049] ​​2) after checking the circuit, pressurize the experimental platform (not more than breakdown pressure) and stabilize at the voltage for a period of time, when the discharge insulation defect 4 does not appear breakdown phenomenon, connect the detection impedance 8 to the high-performance oscilloscope 13, record the discharge amount at the voltage, and then connect the comparative ultrahigh frequency sensor 9 and the integrated sensor 11 to the high-performance oscilloscope 13, adjust the sampling rate to meet the ultrahigh frequency spectrum analysis requirement, when the pulse signals appear in the comparative ultrahigh frequency sensor 9 channel and the integrated sensor 11 channel at the same time, record the data;

[0050] 3) Fourier transform the collected data, compare and analyze the signals collected by the integrated sensor 11 and the comparative ultrahigh frequency sensor 9, if the energy distribution frequency bands of the signals collected by the integrated sensor 11 and the comparative ultrahigh frequency sensor 9 are similar, it indicates that the integrated sensor 11 can effectively sense the ultrahigh frequency signals generated by partial discharge;

[0051] 4) after testing one discharge insulation defect 4, replace the discharge insulation defect 4, repeat steps 1) to 3), test the sensing performance of the integrated sensor to the partial discharge ultrahigh frequency signals under different discharge insulation defects 4.

[0052] The power equipment partial discharge ultrasonic and ultrahigh frequency integrated sensor sensing performance test experimental circuit of the embodiment is shown in Figure 4 , which includes a discharge insulation defect model shell 1, a detection impedance 8, a metal layer 10, an integrated sensor 11, a band-pass filter 12, a high-performance oscilloscope 13, a comparative ultrasonic sensor 14, and an ultrasonic amplifier 15.

[0053] II. The power equipment partial discharge ultrasonic and ultrahigh frequency integrated sensor sensing performance test method is shown in Figure 5 , which includes:

[0054] 1) paste the metal layer 10 to the surface of the discharge insulation defect model shell 1, and ground the metal layer 10, which is used to simulate the metal shell of the power equipment; the integrated sensor 11 and the comparative ultrasonic sensor 14 are pasted to the outer surface of the metal layer 10 using ultrasonic coupling agent and insulating tape, and a metal layer 10 is used to seal the outside of the integrated sensor 11, and attention is paid to avoiding the contact between the metal layer 10 and the surface electrode of the integrated sensor 11;

[0055] 2) connect the integrated sensor 11 and the comparative ultrasonic sensor 14 to the ultrasonic amplifier 15, and then connect to the high-performance oscilloscope 13, and adjust the sampling rate of the oscilloscope to meet the ultrasonic spectrum analysis requirement;

[0056] 3) Before pressurizing, use a small hammer to tap the discharge insulation defect model shell 1, and observe whether there is a tapping pulse signal output on the integrated sensor 11 channel and the contrast ultrasonic sensor 14 channel on the high-performance oscilloscope 13, so as to avoid affecting the subsequent experiment due to line connection problems;

[0057] 4) Before pressurizing, remove the device connected to the high-performance oscilloscope 13, pressurize the experimental platform (not more than the breakdown pressure), and stabilize at the voltage for a period of time. When the discharge insulation defect 4 does not appear breakdown phenomenon, connect the detection impedance 8 to the high-performance oscilloscope 13, record the discharge amount at the voltage, and then connect the contrast ultrasonic sensor 14 connected with the ultrasonic amplifier 15 and the integrated sensor 11 connected with the same model ultrasonic amplifier 15 to the high-performance oscilloscope 13. Adjust the sampling rate and the amplification multiple of the ultrasonic amplifier 15 to meet the requirements. When the contrast ultrasonic sensor 14 channel and the integrated sensor 11 channel appear pulse signals at the same time, record the data;

[0058] 5) Fourier transform the collected data, and compare and analyze the signals collected by the integrated sensor 11 and the contrast ultrasonic sensor 14. If the energy distribution frequency bands of the signals collected by the integrated sensor 11 and the contrast ultrasonic sensor 14 are similar, it indicates that the integrated sensor 11 can effectively perceive the ultrasonic signals generated by partial discharge;

[0059] 6) After testing a kind of discharge insulation defect 4, replace the discharge insulation defect 4 and repeat the above experimental steps to test the perception performance of the integrated sensor to the ultrasonic signals generated by partial discharge under different discharge insulation defects 4.

[0060] The integrated sensor for detecting ultrasonic and ultrahigh frequency signals of the power equipment partial discharge according to the embodiment has the advantages that the integrated sensor can simultaneously perceive the ultrasonic signals and the ultrahigh frequency signals generated by the partial discharge, and the integrated sensor can be used for detecting the partial discharge of the power equipment. Figure 6 The integrated sensor for detecting ultrasonic and ultrahigh frequency signals of the power equipment partial discharge according to the embodiment has the advantages that the integrated sensor can simultaneously perceive the ultrasonic signals and the ultrahigh frequency signals generated by the partial discharge, and the integrated sensor can be used for detecting the partial discharge of the power equipment.

[0061] The integrated sensor for detecting ultrasonic and ultrahigh frequency signals of the power equipment partial discharge according to the embodiment has the advantages that the integrated sensor can simultaneously perceive the ultrasonic signals and the ultrahigh frequency signals generated by the partial discharge, and the integrated sensor can be used for detecting the partial discharge of the power equipment. Figure 7

[0062] 1) Remove the metal layer 10 attached to the discharge insulation defect model shell 1 to a certain size, so that a part of the integrated sensor 11 is in contact with the discharge insulation defect model shell 1 and a part is in contact with the metal layer 10, so that the integrated sensor 11 can perceive the ultrahigh frequency signals generated by the partial discharge; ​

[0063] 2) Put the contrast UHF sensor 9 on the side of the discharge insulation defect model shell 1, stick the contrast ultrasonic sensor 14 and the integrated sensor 11 to the surface of the metal layer 10, and seal the outside of the integrated sensor 11 with the metal layer 10, for simulating the integrated sensor built-in power equipment, wherein the metal layer 10 should avoid contact with the surface electrode of the integrated sensor 11, and the integrated sensor 11 and the contrast ultrasonic sensor 14 are connected to the ultrasonic amplifier 15 and the high-performance oscilloscope 13;

[0064] 3) Lightly tap the discharge insulation defect model shell 1 with a small hammer before pressurization, and observe whether there is a tapping pulse signal output on the high-performance oscilloscope 13 channel of the integrated sensor 11 and the contrast ultrasonic sensor 14 channel, to avoid affecting the subsequent experiment due to line connection problems;

[0065] 4) Pressurize the experimental platform (not more than the breakdown pressure) and stabilize at that voltage for a period of time, and when the discharge insulation defect 4 does not appear breakdown phenomenon, connect the detection impedance 8 to the high-performance oscilloscope 13, record the discharge amount at that voltage, and then connect the contrast UHF sensor 9, the contrast ultrasonic sensor 14 connected with the ultrasonic amplifier 15, and the integrated sensor 11 connected with the same model ultrasonic amplifier 15 to the high-performance oscilloscope 13 respectively, and adjust the sampling rate of the oscilloscope to be able to collect the partial discharge UHF signal perceived by the contrast UHF sensor 9, when the contrast UHF sensor 9 channel, the contrast ultrasonic sensor 14 channel, and the integrated sensor 11 channel appear pulse signals at the same time, collect the data of the three channels;

[0066] 5) Analyze the collected data by time delay method, that is, there is a obvious time difference between the contrast ultrasonic signal time domain waveform and the contrast UHF signal time domain waveform in the collected data waveform, which is recorded as time difference 1, and the size of the time difference 1 is the same as the time of ultrasonic wave propagation from the partial discharge source to the contrast ultrasonic sensor 14 in the medium. If the pulse signal time domain waveform detected by the integrated sensor 11 has a time difference, which is recorded as time difference 2, and the time difference 2 is the same as the time difference 1, it can be shown that the integrated sensor 11 can effectively perceive the ultrasonic signal and UHF signal generated by the partial discharge at the same time;

[0067] 6) After testing one kind of discharge insulation defect 4, replace the discharge insulation defect 4 and repeat the above experimental steps to test the performance of the integrated sensor in perceiving the partial discharge ultrasonic signal and UHF signal at the same time under different discharge insulation defects 4.

[0068] The above merely preferred embodiments of the present application, and not therefore limit the embodiments and protection scope of the present application, for those skilled in the art, it should be realized that the equivalent replacement and obvious changes made by the application description, the resulting scheme should be included in the protection scope of the present application.

Claims

1. A partial discharge ultrasonic, ultra-high frequency integrated sensor performance test method, which tests the following discharge insulation defects: corona discharge defects; air gap discharge defects; surface discharge defects; free particle discharge defects; and suspended discharge defects; characterized in that: The test method comprises: testing the breakdown voltage under different discharge insulation defects; a partial discharge ultrasonic signal sensing performance test method, a partial discharge ultrasonic signal sensing performance test method and a partial discharge ultrasonic signal and UHF signal simultaneous sensing performance test method; ​ The partial discharge ultrasonic signal and UHF signal simultaneous sensing performance test method is realized based on a partial discharge ultrasonic signal and UHF signal simultaneous sensing performance test circuit, and the test circuit comprises: a discharge insulation defect model shell, a detection impedance, a comparative UHF sensor, a metal layer, an integrated sensor, a band-pass filter, an oscilloscope, a comparative ultrasonic sensor and an ultrasonic amplifier; the discharge insulation defect model shell is made of a non-metal material; the test method comprises the following steps: Step 21: remove a part of the metal layer attached to the discharge insulation defect model shell, so that a part of the integrated sensor is in contact with the discharge insulation defect model shell and another part is in contact with the metal layer, so that the integrated sensor senses the UHF signal generated by the partial discharge; Step 22: place the comparative UHF sensor on the side of the discharge insulation defect model shell, stick the comparative ultrasonic sensor and the integrated sensor to the surface of the metal layer, and seal the outside of the integrated sensor with the metal layer to simulate that the integrated sensor is built-in in the power equipment, wherein the metal layer avoids contact with the surface electrode of the integrated sensor, the integrated sensor and the comparative ultrasonic sensor are connected to the ultrasonic amplifier and the oscilloscope; Step 23: knock the discharge insulation defect model shell before pressurization, and observe whether there is a knocking pulse signal output on the integrated sensor channel and the comparative ultrasonic sensor channel of the oscilloscope to confirm that the circuit connection is normal; Step 24: pressurize the experimental platform, the pressure does not exceed the breakdown pressure, and stabilize at the voltage for a certain period of time, the discharge insulation defect does not appear breakdown phenomenon, connect the detection impedance to the oscilloscope, record the discharge amount under the voltage, then connect the comparative UHF sensor, the comparative ultrasonic sensor connected with the ultrasonic amplifier and the integrated sensor connected with the same model ultrasonic amplifier to the oscilloscope respectively, adjust the sampling rate of the oscilloscope to collect the partial discharge UHF signal sensed by the comparative UHF sensor, when the pulse signals of the comparative UHF sensor channel, the comparative ultrasonic sensor channel and the integrated sensor channel appear at the same time, collect the data of the three channels; Step 25: analyze the collected data by time delay method, the time difference between the time domain waveform of the comparative ultrasonic signal and the time domain waveform of the comparative UHF signal in the collected data waveform is recorded as time difference 1, the size of the time difference 1 is the same as the time of ultrasonic wave propagation from the partial discharge source to the comparative ultrasonic sensor in the medium; if the pulse signal time domain waveform detected by the integrated sensor exists time difference, recorded as time difference 2, and the time difference 2 is the same as the time difference 1, then the integrated sensor simultaneously senses the ultrasonic signal and the UHF signal generated by the partial discharge. Step 26, after testing a discharge insulation defect, replace the discharge insulation defect, repeat steps 21-25, test the performance of the integrated sensor under different discharge insulation defects for simultaneously sensing partial discharge ultrasonic signals and UHF signals.

2. The method according to claim 1, wherein the method is characterized in that: The partial discharge UHF signal sensing performance test method is realized based on a partial discharge UHF signal sensing performance test circuit, which includes: a discharge insulation defect model shell, a detection impedance, a comparative UHF sensor, an integrated sensor, a band-pass filter, and an oscilloscope; the discharge insulation defect model shell is made of non-metallic material; the test method includes the following steps: Step 01, first, the integrated sensor is pasted to the surface of the discharge insulation defect model shell with ultrasonic coupling agent and insulating tape, and the comparative UHF sensor is placed on the side of the discharge insulation defect model shell, or a flexible UHF sensor is pasted to the surface of the discharge insulation defect model shell using insulating tape; Step 02, after checking the circuit, the experimental platform is pressurized, not exceeding the breakdown voltage, and the voltage is stabilized for a certain period of time, when the discharge insulation defect does not appear breakdown phenomenon, the detection impedance is connected to the oscilloscope, and the discharge quantity under the voltage is recorded, the comparative UHF sensor and the integrated sensor are connected to the oscilloscope, and the sampling rate is adjusted to meet the UHF spectrum analysis requirements, when the comparative UHF sensor channel and the integrated sensor channel appear pulse signals at the same time, the data is recorded; Step 03, Fourier transform is performed on the collected data, and comparative analysis is performed on the signals collected by the integrated sensor and the comparative UHF sensor, if the energy distribution frequency bands of the signals collected by the integrated sensor and the comparative UHF sensor are similar, then the integrated sensor can effectively sense the UHF signals generated by partial discharge; Step 04, after testing a discharge insulation defect, replace the discharge insulation defect, repeat steps 01-03, test the sensing performance of the integrated sensor under different discharge insulation defects for partial discharge UHF signals.

3. The method according to claim 1, wherein the method is characterized in that: The partial discharge ultrasonic signal sensing performance test method is realized based on a partial discharge ultrasonic signal sensing performance test circuit, which includes: a discharge insulation defect model shell, a detection impedance, a metal layer, an integrated sensor, a band-pass filter, an oscilloscope, a comparative ultrasonic sensor, and an ultrasonic amplifier; the discharge insulation defect model shell is made of non-metallic material; the test method includes the following steps: Step 11, the metal layer is pasted to the surface of the discharge insulation defect model shell and grounded, which is used to simulate the metal shell of the power equipment; the integrated sensor and the comparative ultrasonic sensor are pasted to the outer surface of the metal layer using ultrasonic coupling agent and insulating tape, wherein the metal layer is sealed outside the integrated sensor and avoids contact between the metal layer and the surface electrode of the integrated sensor; Step 12, connect the integrated sensor and the comparative ultrasonic sensor to the ultrasonic amplifier, and then to the oscilloscope, and adjust the sampling rate of the oscilloscope to meet the ultrasonic spectrum analysis; Step 13, knock the discharge insulation defect model shell before pressurization, observe whether there is a knock pulse signal output on the oscilloscope integrated sensor channel and the contrast ultrasonic sensor channel, and confirm that the circuit connection is normal; Step 14, before pressurization, pull out the equipment connected with the oscilloscope, pressurize the experimental platform, and do not exceed the breakdown pressure. The discharge insulation defect does not appear breakdown phenomenon, connect the detection impedance to the oscilloscope, record the discharge amount under the voltage; connect the contrast ultrasonic sensor with ultrasonic amplifier and the integrated sensor with the same type ultrasonic amplifier to the oscilloscope, adjust the sampling rate and the ultrasonic amplifier amplification multiple to meet the requirements, and record the data when the pulse signal appears in the contrast ultrasonic sensor channel and the integrated sensor channel at the same time; Step 15, Fourier transform the collected data, compare and analyze the signals collected by the integrated sensor and the contrast ultrasonic sensor, if the energy distribution frequency bands of the signals collected by the integrated sensor and the contrast ultrasonic sensor are similar, the integrated sensor can effectively perceive the ultrasonic signals generated by the partial discharge; Step 16, after testing one kind of discharge insulation defect, replace the discharge insulation defect, repeat steps 11-15, and test the perception performance of the integrated sensor to the ultrasonic signals of the partial discharge under different discharge insulation defects.

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