A UHF Partial Discharge Sensor for GIS

Abstract

The utility model relates to the technical field of online monitoring of electric power equipment, specifically a UHF partial discharge sensor for GIS. It comprises a GIS insulating basin body, the circumferential outer wall of the GIS insulating basin body is covered with a metal ring, the GIS insulating basin body has a metal auxiliary electrode near the metal ring, a plurality of grounding points evenly distributed along the circumferential direction are reserved on the metal auxiliary electrode, a UHF sensor is installed at one grounding point, the UHF sensor is connected to a coaxial cable through a three-way connector, and the other end of the three-way connector is connected to an overvoltage protector. The sensor has strong anti-interference ability, high sensitivity and high reliability, and can realize efficient and accurate monitoring of partial discharge phenomena of GIS equipment.

Description

Technical Field

[0001] The utility model relates to the technical field of online monitoring of electric power equipment, in particular to an ultra-high frequency partial discharge sensor for GIS. Background Art

[0002] GIS (gas insulated switchgear) is widely used in high-voltage power systems due to its excellent insulation performance and small footprint. However, the high electric field strength and limited insulation margin inside the GIS means that once insulation defects occur, it may cause equipment failure or even power outages. Partial discharge is an early sign of insulation aging or damage in GIS equipment, which can be detected by UHF sensors. This sensor can capture the UHF electromagnetic waves generated by partial discharge, thereby monitoring the insulation status inside the equipment. The UHF sensor is the core component of the partial discharge online monitoring system, and its performance directly affects the sensitivity and accuracy of the detection system. The design and optimization of the sensor is crucial to improving the detection frequency band and sensitivity.

[0003] The existing GIS partial discharge UHF detection device uses external UHF sensors and internal UHF sensors to collect signals. External UHF sensors, that is, UHF sensors installed outside the metal shell of GIS, are susceptible to electromagnetic interference from external radio stations or wireless communications, have low monitoring sensitivity, insufficient coverage, and potential risks of partial discharge signal leakage. Internal sensors may be limited by the internal structure of GIS, and it is difficult to ensure the safe insulation distance of GIS, which may cause signal attenuation and affect the signal collection effect. In addition, the installation and maintenance of internal sensors may be more complicated and difficult than external sensors. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a UHF partial discharge sensor for GIS, which has strong anti-interference ability, high sensitivity and high reliability, so as to realize efficient and accurate monitoring of partial discharge phenomenon of GIS equipment.

[0005] In order to solve the technical problem, the technical solution adopted by the utility model is: a UHF partial discharge sensor for GIS, including a GIS insulating basin body, the circumferential outer wall of the GIS insulating basin body is covered with a metal ring, the GIS insulating basin body has a metal auxiliary electrode near the metal ring, a plurality of grounding points evenly distributed along the circumferential direction of the metal auxiliary electrode are reserved on the metal auxiliary electrode, a UHF sensor is installed at one grounding point, the UHF sensor is connected to a coaxial cable through a three-way connector, and the other end of the three-way connector is connected to an overvoltage protector.

[0006] Furthermore, the metal auxiliary electrode is cast in the epoxy resin of the GIS insulation basin body.

[0007] Further, the metal ring and the metal auxiliary electrode are connected together through a spring and a screw passing through a grounding point.

[0008] Furthermore, a sealing ring is provided at the connection position between the UHF sensor and the GIS insulating basin body.

[0009] Furthermore, the three-way connector and the coaxial cable are connected via a coaxial cable connector assembly, and the coaxial cable connector assembly includes a male connector and a female connector that are correspondingly inserted.

[0010] Further, the three-way connector is connected to the female connector, and the coaxial cable adapter is connected to the male connector.

[0011] Furthermore, the metal ring is a metal aluminum ring.

[0012] Furthermore, three grounding points evenly distributed along the circumference of the metal auxiliary electrode are reserved.

[0013] Beneficial effects of the utility model: The utility model provides a UHF partial discharge sensor for GIS with strong anti-interference ability and accurate positioning, so as to realize efficient and accurate monitoring of partial discharge phenomenon of GIS equipment. The UHF partial discharge sensor is compatible with all pot-type insulators of the same size structure, and can effectively detect partial discharge signals in the equipment within a certain frequency band. The sensing body does not use electronic devices such as resistors and capacitors, and will not cause GIS electric field distortion and endanger the safety of the body during installation. Compared with the prior art, the device described in the utility model can more accurately capture and identify partial discharge phenomenon of GIS equipment, improve the anti-interference ability, and can accurately locate the position of partial discharge, which provides convenience for the maintenance and repair of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the structure of the utility model;

[0015] Figure 2 It is a structural schematic diagram of a UHF sensor;

[0016] In the figure: 1. GIS insulating basin body, 2. Metal aluminum ring, 3. Metal auxiliary electrode, 4. Spring and screw, 5. UHF sensor, 6. Sealing ring, 7. T-joint, 8. Coaxial cable, 9. Overvoltage protector. DETAILED DESCRIPTION

[0017] The utility model is further described below in conjunction with the accompanying drawings and specific embodiments.

[0018] Example 1

[0019] This embodiment discloses a UHF partial discharge sensor for GIS, referring to Figure 1 , 2 , including a GIS insulating basin body 1, the circumferential outer wall of the GIS insulating basin body 1 is covered with a metal aluminum ring 2, a metal auxiliary electrode 3 is provided near the metal aluminum ring 2 on the GIS insulating basin body 1, three grounding points evenly distributed along the circumferential direction of the metal auxiliary electrode 3 are reserved, a UHF sensor 5 is installed at one grounding point, the UHF sensor 5 is connected to a coaxial cable 8 through a three-way connector 7, and the other end of the three-way connector 7 is connected to an overvoltage protector 9.

[0020] In this embodiment, the metal auxiliary electrode 3 is cast in the epoxy resin of the GIS insulating basin body 1. The metal aluminum ring 2 and the metal auxiliary electrode 3 are connected together by a spring and a screw 4 passing through the grounding point, and the screw is grounded. The spring is elastic and can automatically adjust the connection tightness between the screw and the grounding electrode to a certain extent, ensuring good contact between the screw and the electrode and maintaining a stable grounding connection; it can effectively buffer and absorb shock and vibration to avoid damage to the metal auxiliary electrode 3. The screw seals the position. The function of the metal auxiliary electrode 3 is to compensate or evenly distribute static electricity, and to eliminate the influence of possible air pockets between the epoxy material and the aluminum ring. Epoxy resin has high chemical stability, thermal stability, and reliable sealing performance, which can effectively ensure the sealing of the gas in the GIS room.

[0021] A sealing ring 6 is provided at the connection portion between the UHF sensor 5 and the GIS insulating basin body 1 to ensure that no debris or rainwater can penetrate in severe weather and environment.

[0022] In this embodiment, the three-way connector 7 and the coaxial cable 8 are connected through a coaxial cable connector assembly, and the coaxial cable connector assembly includes a male connector and a female connector that are correspondingly inserted. Specifically, the three-way connector 7 is connected to the female connector, and the coaxial cable converter is connected to the male connector. The coaxial cable 8 connected to the UHF sensor is realized through the three-way connector 7, and the overvoltage protector 9 is installed at the other end of the three-way connector to realize the grounding of the power frequency signal and the effective transmission of the UHF signal.

[0023] The UHF partial discharge sensor of this embodiment forms a UHF coupling antenna to couple the UHF partial discharge signal generated in the GIS through the connected sensor 5, metal auxiliary electrode 3 and metal aluminum ring 2. The function of the metal auxiliary electrode 3 is to compensate or evenly distribute the static electricity and eliminate the air pockets that may exist between the epoxy material and the aluminum ring. The function of the metal aluminum ring 2 is to improve the distributed voltage and electric field distribution of the insulator and improve the measurement accuracy.

[0024] The above description is only the basic principle and preferred embodiments of the present invention. Improvements and substitutions made by those skilled in the art based on the present invention belong to the protection scope of the present invention.

Claims

1. A UHF partial discharge sensor for GIS, comprising a GIS insulating basin body, characterized in that: The outer circumferential wall of the GIS insulating basin body is covered with a metal ring, and a metal auxiliary electrode is provided near the metal ring on the GIS insulating basin body. A plurality of grounding points evenly distributed along the circumferential direction are reserved on the metal auxiliary electrode. A UHF sensor is installed at one grounding point. The UHF sensor is connected to the coaxial cable through a three-way connector, and the other end of the three-way connector is connected to the overvoltage protector.

2. The ultra-high frequency partial discharge sensor for GIS according to claim 1, characterized in that: The metal auxiliary electrode is cast in the epoxy resin of the GIS insulation basin body.

3. The ultra-high frequency partial discharge sensor for GIS according to claim 1 or 2, characterized in that: The metal ring and the metal auxiliary electrode are connected together by a spring and a screw passing through the grounding point.

4. The ultra-high frequency partial discharge sensor for GIS according to claim 1, characterized in that: A sealing ring is provided at the connection position between the UHF sensor and the GIS insulating basin body.

5. The ultra-high frequency partial discharge sensor for GIS according to claim 1, characterized in that: The three-way connector and the coaxial cable are connected through a coaxial cable connector assembly, and the coaxial cable connector assembly includes a male connector and a female connector that are correspondingly inserted.

6. The ultra-high frequency partial discharge sensor for GIS according to claim 5, characterized in that: The tee connector is connected to the female connector and the coaxial cable adapter is connected to the male connector.

7. The ultra-high frequency partial discharge sensor for GIS according to claim 1, characterized in that: The metal ring is a metal aluminum ring.

8. The ultra-high frequency partial discharge sensor for GIS according to claim 1, characterized in that: Three grounding points evenly distributed along the circumference of the metal auxiliary electrode are reserved.

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