A multi-signal fusion monitoring method for partial discharge faults of GIS pot-type insulators

Abstract

The present invention discloses a multi-signal fusion monitoring method for partial discharge faults of GIS pot-type insulators, and belongs to the technical field of GIS pot-type insulator fault detection. The method comprises the following steps: 1) designing a GIS pot-type insulator defect simulation test piece, building a simulation device, and installing electrical and optical signal monitoring equipment on the device; 2) applying voltage through a test pressurization device to stimulate partial discharge signals of preset defects of GIS pot-type insulators; 3) connecting an industrial computer with the monitoring equipment to collect optical and electrical signal data when partial discharge occurs in the test GIS pot-type insulator. The present invention can monitor the operating conditions of GIS pot-type insulators in real time without power outages, and collect reliable, accurate, and comprehensive monitoring data for judging the working status of GIS insulators, making up for the shortcoming of poor timeliness of existing monitoring methods.

Description

Technical Field

[0001] The invention relates to the technical field of GIS pot-type insulator fault detection, and more specifically to a multi-signal fusion monitoring method for GIS pot-type insulator partial discharge faults. Background Art

[0002] Surface defects of GIS pot-type insulators may cause partial discharge during GIS operation. Partial discharge signals contain rich equipment insulation status information. By performing partial discharge detection on GIS pot-type insulators, latent insulation faults can be effectively discovered. At present, the most commonly used GIS pot-type insulator operation status monitoring methods include pulse current distribution measurement method, ultra-high frequency signal monitoring, and visible light image monitoring. However, these common monitoring methods have certain limitations. The pulse current distribution measurement method has poor anti-interference ability and low sensitivity in field testing, and its application and promotion are easily restricted; the installation position of the ultra-high frequency signal sensor on site has a great influence on its measurement effect, so the antenna design and signal acquisition system design of the ultra-high frequency signal sensor are extremely demanding; the visible light image monitoring method requires that the installation position must ensure that the monitoring device is visible at a sight distance and cannot be blocked, otherwise there will be a monitoring "blind spot".

[0003] In order to ensure safe and reliable power supply, the focus of power equipment detection strategy has gradually shifted from routine power outage tests to more flexible and effective live detection tests in recent years. In order to make up for the limitations of traditional monitoring methods for partial discharge of GIS pot insulators and achieve high-precision monitoring of the operating status of GIS pot insulators, it is urgent to explore a multi-signal fusion monitoring method for partial discharge faults of GIS pot insulators without power outages. Summary of the invention

[0004] The purpose of this method is to propose a multi-signal fusion monitoring method for partial discharge faults of GIS pot-type insulators to solve the above technical problems.

[0005] To achieve the above object, the present invention provides a multi-signal fusion monitoring method for partial discharge faults of GIS pot-type insulators, characterized in that the method comprises the following steps:

[0006] Step 1: Design a GIS pot-type insulator defect simulation specimen, build a GIS pot-type insulator operation simulation device, and install electrical and optical signal monitoring equipment on the device, including a partial discharge detector, a UHF partial discharge sensor, an ultraviolet imager, and a photomultiplier tube;

[0007] Step 2: applying voltage through a test pressure device to stimulate a partial discharge signal of a preset defect of the GIS pot-type insulator;

[0008] Step 3: Use an industrial computer to connect to the monitoring equipment to collect optical and electrical signal data when partial discharge occurs in the test GIS pot-type insulator.

[0009] Furthermore, the detection circuit of the partial discharge detector in step 1 is connected in parallel with the test product, and the detection circuit realizes the detection of the discharge pulse current signal by connecting the detection impedance in series with the coupling capacitor; the UHF partial discharge sensor is an external microstrip antenna structure, which is installed at the fixed flange outside the GIS pot insulator.

[0010] The UV imaging detector and the photomultiplier tube are installed at the observation window. The specific installation height of the UV imaging detector and the photomultiplier tube is kept on the same horizontal line with the center point of the observation window of the air-filled pressurized cavity. The minimum horizontal distance l1 from the installation point to the center of the GIS pot insulator is calculated as follows:

[0011]

[0012] Where, l1 is the minimum distance that meets the imaging range requirements, in mm; k1 is the correction factor for the installation height of the UV imaging detector; r1 is the radius of the observation window, in mm; θ1 is the horizontal field of view of the UV imaging detector, in °; θ2 is the vertical field of view of the UV imaging detector, in °; l gc is the length of the observation window structure, in mm;

[0013] The maximum horizontal distance l2 from the installation point to the center of the GIS pot insulator is calculated as follows:

[0014]

[0015] Wherein, l2 is the maximum installation horizontal distance that meets the imaging accuracy requirements, in mm; r1 is the observation window radius, in mm; v is the imaging distance of the ultraviolet imaging detector, in mm; f is the focal length of the objective lens of the ultraviolet imaging detector, in mm; a is the setting gain value of the ultraviolet imaging detector;

[0016] The horizontal distance l from the installation point of the UV imaging detector and the photomultiplier tube to the center of the GIS basin insulator must meet l1 <l<l2。

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The present invention monitors the electrical signals of GIS pot-type insulators in real time through a partial discharge detector and a UHF partial discharge sensor, and monitors the optical signals of GIS pot-type insulators in real time through an ultraviolet imaging detector and a photomultiplier tube, thereby realizing real-time monitoring of the state of GIS pot-type insulators without power outage, providing reliable, accurate and comprehensive monitoring data for judging the working state of GIS pot-type insulators, and making up for the shortcoming of poor timeliness of existing monitoring methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is an implementation flow chart of the multi-signal fusion monitoring method for partial discharge fault of GIS pot-type insulator in the present invention;

[0020] Figure 2 It is a schematic diagram of a multi-signal fusion monitoring device for partial discharge faults of GIS pot-type insulators in the present invention;

[0021] Figure 3 It is a schematic diagram of the installation of the ultra-high frequency partial discharge sensor in the present invention;

[0022] Figure 4 It is a schematic diagram of the installation of the ultraviolet imaging detector and the photomultiplier tube in the present invention;

[0023] In the figure, 1. GIS pot-type insulator defect simulation specimen; 2. Test pressurization device; 3. Inflatable pressurization chamber; 4. High-voltage bushing; 5. Internal guide rod; 6. Equalizing cover; 7. Host computer; 8. Partial discharge detector; 9. Detection impedance; 10. Coupling capacitor; 11. No. 1 UHF partial discharge sensor; 12. No. 2 UHF partial discharge sensor; 13. Ultraviolet imaging detector; 14. Photomultiplier tube; 15. Observation window; 16. Fixed flange. DETAILED DESCRIPTION

[0024] The following is a clear and complete description of the technical solution in the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0025] Embodiment 1

[0026] This embodiment proposes a multi-signal fusion monitoring method for partial discharge faults of GIS pot-type insulators. Figure 1 As shown, the method comprises the following steps:

[0027] Step 1. Design GIS pot-type insulator defect simulation specimen 1, design 220kV 3 times scaled pot-type insulator defect specimen and 110kV real pot-type insulator defect specimen. Defect specimen defect types include common defects such as air gap defects, insert burr defects, single metal particle defects and metal particle group defects. Among them, air gap defects and insert burr defects are internal defects and need to be built-in during the production process of pot-type insulator specimens. Single metal particle defects and metal particle group defects are external defects and can be placed on the surface of normal pot-type insulator specimens. In order to facilitate the observation of optical phenomena during the development of internal defects, when making GIS pot-type insulator defect simulation specimens, the specimens are made into transparent specimens by controlling the material casting process.

[0028] A GIS pot-type insulator operation simulation device is built, which includes a test pressurization device 2, a gas-filled pressurization cavity 3, a high-voltage bushing 4, an internal guide rod 5, a GIS pot-type insulator defect simulation specimen 1, a voltage-equalizing cover 6, and a host computer 7. A 110kv high-voltage bushing is installed inside the gas-filled pressurization cavity 3, and a reducing flange is arranged in the cavity, which can be compatible with 110kv and 220kv real pot-type insulators and a 3-fold scale model of a 220kv pot-type insulator. The test pressurization device 2, the high-voltage bushing 4, the GIS pot-type insulator defect simulation specimen 1 and the voltage-equalizing cover 6 are connected in sequence to ensure that the test high-voltage output can apply voltage to the GIS pot-type insulator defect simulation specimen 1 through the high-voltage bushing 4 and the internal guide rod 5 of the cavity.

[0029] Electrical and optical signal acquisition equipment is installed on the device. The detection of the partial discharge detector 8 adopts a parallel test circuit. The detection circuit is connected to ground through a detection impedance 9 in series with a coupling capacitor 10. The signal transmission line connects the detection circuit and the host computer 7 to realize the collection of discharge pulse current signals. The ultra-high frequency partial discharge sensor is an external microstrip antenna structure. The first ultra-high frequency partial discharge sensor 11 and the second ultra-high frequency partial discharge sensor 12 are respectively installed at the fixed flanges 16 on both sides of the outer side of the GIS basin insulator, and are connected to the host computer 7 via the signal transmission line to realize the ultra-high frequency partial discharge signal collection.

[0030] The ultraviolet imaging detector 13 and the photomultiplier tube 14 are installed at the observation window. The specific installation height of the ultraviolet imaging detector 13 and the photomultiplier tube 14 is kept on the same horizontal line with the center point of the observation window 15 of the air-filled pressurized cavity. The minimum horizontal distance l1 from the installation point to the center of the GIS pot insulator is calculated as follows:

[0031]

[0032] Wherein, l1 is the minimum distance meeting the imaging range requirement, with the unit of mm; k1 is the installation height correction coefficient of the ultraviolet imaging detector, k1 = 1.42; r1 is the radius of the observation window, with the unit of mm; θ1 is the horizontal field of view angle of the ultraviolet imaging detector, with the unit of °; θ2 is the vertical field of view angle of the ultraviolet imaging detector, with the unit of °; l gc is the length of the observation window structure, with the unit of mm.

[0033] The calculation method of the maximum horizontal distance l2 from its installation point to the center of the GIS pot insulator is as follows:

[0034]

[0035] Wherein, l2 is the maximum installation horizontal distance meeting the imaging accuracy requirement, with the unit of mm; r1 is the radius of the observation window, with the unit of mm; v is the imaging image distance of the ultraviolet imaging detector, with the unit of mm; f is the objective focal length of the ultraviolet imaging detector, with the unit of mm; a is the set gain value of the ultraviolet imaging detector, a = 260.

[0036] The horizontal distance l from the installation points of the ultraviolet imaging detector 13 and the photomultiplier tube 14 to the observation window needs to satisfy l1 < l < l2. The ultraviolet imaging detector 13 and the photomultiplier tube 14 are connected to the upper computer 7 through signal transmission lines to realize the acquisition of partial discharge optical signals.

[0037] Step 2: Apply voltage through the test voltage application device 2 to excite the partial discharge signal of the preset defect of the GIS pot insulator.

[0038] The test voltage application device 2 applies voltage. The partial discharge inception test voltage of the test model is set to 61.3 kV. During the test process, the step-up voltage method is adopted until surface flashover occurs on the GIS pot insulator in the gas-filled pressure chamber. The duration of each test stage is 60 minutes, and the voltage difference between test stages is 5.5 kV. When the voltage rises to 94.0 kV, surface flashover occurs on the insulator after 90 seconds, and the test terminates.

[0039] Step 3: The upper computer 7 with acquisition software is connected to four acquisition devices, and uses the partial discharge detector 8, the first ultra-high frequency partial discharge sensor 11 and the second ultra-high frequency partial discharge sensor 12 to collect the electrical signal data during the discharge process of the GIS pot insulator, and uses the ultraviolet imager 13 and the photomultiplier tube 14 to collect the optical signal data during the discharge process of the GIS pot insulator.

[0040] The above content is only an explanation of the structure of the present invention. Those skilled in the art of this technology make various modifications or supplements to the described specific structure. As long as they do not deviate from the structure of the invention or exceed the scope defined by this claim book, they should all fall within the protection scope of the present invention.

Claims

1. A multi-signal fusion monitoring method for partial discharge fault of GIS pot-type insulator, characterized in that: The method comprises the following steps: Step 1: Design a GIS pot-type insulator defect simulation specimen, build a GIS pot-type insulator operation simulation device, and install electrical and optical signal monitoring equipment on the device, including a partial discharge detector, a UHF partial discharge sensor, an ultraviolet imager, and a photomultiplier tube; The detection circuit of the partial discharge detector is connected in parallel with the test object, and the detection circuit realizes the detection of the discharge pulse current signal by connecting the detection impedance in series with the coupling capacitor; the UHF partial discharge sensor is an external microstrip antenna structure, which is installed at the fixed flange outside the GIS basin insulator; The ultraviolet imaging detector and the photomultiplier tube are installed at the observation window. The specific installation height of the ultraviolet imaging detector and the photomultiplier tube is kept on the same horizontal line with the center point of the observation window of the air-filled pressurized cavity. The minimum horizontal distance l1 from the installation point to the center of the GIS pot insulator is calculated as follows: Where, l1 is the minimum distance that meets the imaging range requirements, in mm; k1 is the correction factor for the installation height of the UV imaging detector; r1 is the radius of the observation window, in mm; θ1 is the horizontal field of view of the UV imaging detector, in °; θ2 is the vertical field of view of the UV imaging detector, in °; l gc is the length of the observation window structure, in mm; The maximum horizontal distance l2 from the installation point to the center of the GIS pot insulator is calculated as follows: Wherein, l2 is the maximum installation horizontal distance that meets the imaging accuracy requirements, in mm; r1 is the observation window radius, in mm; v is the imaging distance of the ultraviolet imaging detector, in mm; f is the focal length of the objective lens of the ultraviolet imaging detector, in mm; a is the setting gain value of the ultraviolet imaging detector; The horizontal distance l from the installation point of the UV imaging detector and the photomultiplier tube to the center of the GIS basin insulator must meet l1 <l<l2; Step 2: applying voltage through a test pressure device to stimulate a partial discharge signal of a preset defect of the GIS pot-type insulator; Step 3: Use an industrial computer to connect to the monitoring equipment to collect optical and electrical signal data when partial discharge occurs in the test GIS pot-type insulator.

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