An optical voltage sensor mounting device for GIS bus voltage measurement

Abstract

The present invention discloses an optical voltage sensor mounting device for measuring GIS bus voltage, comprising a mounting device housing, a matching sensor bracket and a pressure plate arranged in the mounting device housing for mounting an optical voltage sensor, an optical fiber flange arranged on the device housing and used in conjunction with the optical voltage sensor, and a connecting plate for fixing the mounting device housing to the GIS housing flange; the mounting device housing is designed with an opening surface that fits with a pot-type insulator and a GIS housing flange; the optical voltage sensor is crimped and fixed to the bracket by adjusting the fastening screws at both ends of the pressure plate. The present invention fixes the optical voltage sensor on the outer surface of the insulating part of the GIS pot-type insulator by means of the mounting device housing and the connecting plate, and uses the optical voltage sensor to measure the electric field distribution therein, which can not only realize the measurement of the GIS bus voltage, but also realize the installation, disassembly, operation and maintenance of the sensor without affecting the operation of the primary equipment.

Description

Technical Field

[0001] The invention belongs to the technical field of electrical measurement, and relates to an optical voltage sensor for an ultra-high voltage alternating current power transmission and transformation system, and in particular to an optical voltage sensor hanging device for measuring GIS bus voltage. Background Art

[0002] Gas Insulated Switchgear (GIS) in ultra-high voltage AC transmission and transformation systems has significant advantages such as small footprint, good sealing, low environmental impact, high operating reliability, long maintenance cycle, and low operating costs. It has been widely used in my country's power grid. The operating GIS not only faces threats such as resonance and lightning overvoltage from the power system, but also has to withstand the fast transient overvoltage (VFTO) generated by its own disconnector, grounding switch and circuit breaker operation. The existence of these overvoltages seriously threatens the stable operation of GIS substations and even power systems. The existing voltage measurement equipment in substations has a low frequency response and cannot meet the measurement requirements of transient overvoltages.

[0003] At present, many research institutions have proposed voltage measurement methods based on the Pokels effect. The patent application document with application number CN201510187781.4 discloses an all-optical overvoltage monitoring device for power systems, which has high measurement reliability and a wide frequency range, consistent response at power frequency and overvoltage frequency, and can take into account the measurement of power frequency voltage as well as internal and external overvoltage.

[0004] Based on this type of measurement method, "Optical voltage transformer integrated in GIS cavity" (patent application number CN201110288616.X) and "An optical VFTO measurement system based on Pockels effect" (patent application number CN201410285845.X) both proposed installing optical voltage sensors inside GIS to measure bus voltage. However, the built-in optical voltage sensor not only greatly increases the design and installation costs, but also brings difficulties to the operation and maintenance of the equipment.

[0005] Therefore, built-in optical voltage sensors have become a major obstacle to the development and application of optical voltage sensors on GIS. It is urgent to develop a convenient, fast, safe and stable installation method to realize the installation and application of optical voltage sensors on GIS. Summary of the invention

[0006] In view of the problems existing in the prior art such as inconvenient installation and maintenance and high cost caused by the built-in optical voltage sensor, the present invention proposes an optical voltage sensor hanging device for GIS bus voltage measurement, which can conveniently, safely and firmly fix the optical voltage sensor on the GIS casing to realize the measurement of GIS bus voltage.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions.

[0008] The present invention provides an optical voltage sensor mounting device for measuring GIS bus voltage, which fixes the optical voltage sensor on the outer surface of the insulating part of the GIS pot-type insulator, and uses the optical voltage sensor to measure the electric field distribution at the location, thereby realizing the measurement of the GIS bus voltage. The mounting device includes a mounting device housing, a matching sensor bracket and a pressure plate arranged in the mounting device housing for mounting the optical voltage sensor, an optical fiber flange arranged on the mounting device housing and used in conjunction with the optical voltage sensor, and a connecting plate for fixing the mounting device housing to the GIS housing flange; the mounting device housing is designed with an opening surface that fits the pot-type insulator and the GIS housing flange; the number of the brackets and the pressure plate are both two, and the brackets are symmetrically distributed at the center of the bottom surface of the mounting device housing, and the distance between the two is less than the length or width of the optical voltage sensor, and the optical voltage sensor is crimped and fixed to the bracket by adjusting the fastening screws at both ends of the pressure plate.

[0009] The optical voltage sensor hanging device for GIS busbar voltage measurement can be designed as a rectangular stainless steel box with one side open for easy installation and effective shielding of electromagnetic interference in the substation. A pair of contact edges on the opening surface are designed as straight lines parallel to the width direction of the GIS pot-type insulator, and their length is slightly larger than the width of the outer surface of the GIS pot-type insulator. The other pair of contact edges are designed as arcs that match the curvature of the outer surface of the GIS pot-type insulator, thereby achieving a close fit between the opening surface of the hanging device shell and the pot-type insulator and the GIS shell flange.

[0010] The optical voltage sensor mounting device for measuring GIS busbar voltage needs to have a design height of the bracket determined according to the mounting device housing depth and the curvature of the outer surface of the GIS pot-type insulator, so that the optical voltage sensor is as close to the outer surface of the GIS pot-type insulator as possible without contacting it, and maintains a distance of about 3 to 5 cm from the inner wall of the mounting device housing. In a preferred implementation, the gap between the optical voltage sensor and the outer surface of the GIS pot-type insulator is within 1 cm.

[0011] The optical voltage sensor mounting device for GIS bus voltage measurement has two optical fiber flanges, the inward interfaces of the two optical fiber flanges are respectively connected to the input and output optical fiber interfaces of the optical voltage sensor, and the outward interfaces are connected to the transmission optical fiber interface. The input and output optical fibers of the optical voltage sensor are led out to the outside of the mounting device through the two optical fiber flanges, thereby realizing the connection between the optical voltage sensor and its matching laser source and light detector.

[0012] The optical voltage sensor mounting device for measuring GIS bus voltage is designed with slots on the connecting plate. The first bolts and the second bolts on the pot-type insulator and the GIS housing flange provided on the outer side of the mounting device housing are fixed in the slots of the connecting plate through nuts matched therewith, so that the mounting device housing and the GIS housing are connected to the same potential. The diameters of the first bolt and the second bolt are equal. The material of the connecting plate is flat steel. The width of the slots of the connecting plate is equal to the diameters of the first bolt and the second bolt.

[0013] In order to prevent the electric field around the optical voltage sensor from being distorted, the above-mentioned optical voltage sensor hanging device for GIS bus voltage measurement is made of insulating materials with a small relative dielectric constant, such as nylon, polytetrafluoroethylene, etc., as the bracket, pressure plate and fastening screws used to fix the bracket and pressure plate.

[0014] In order to achieve effective measurement of GIS bus voltage, the appropriate installation position of the hanging device and the optical voltage sensor can be selected according to the different structures of GIS equipment. When it is applied to single-pole single-box GIS equipment with open pot insulators, the hanging device is suitable for hanging at any position on the outer surface of the pot insulator. When it is applied to three-pole common box GIS equipment with open pot insulators, three hanging devices need to be placed at the same time, and they are placed on the surface of the pot insulator closest to the three-phase bus. When it is applied to single-pole single-box GIS equipment with metal ring pot insulators, it needs to be hung at the casting hole of the pot insulator.

[0015] Compared with the prior art, the optical voltage sensor mounting device for GIS bus voltage measurement of the present invention has the following beneficial effects:

[0016] (1) The mounting device provided by the present invention fixes the optical voltage sensor on the outer surface of the insulating part of the GIS pot-type insulator through the mounting device housing and the connecting plate, and uses the optical voltage sensor to measure the electric field distribution at the location, which can not only measure the GIS bus voltage, but also realize the installation, disassembly and operation and maintenance of the sensor without affecting the operation of the primary equipment;

[0017] (2) The hook device provided by the present invention, the fixed connection between the hook device housing and the GIS housing flange, and the fixed connection between the optical voltage sensor bracket, the pressure plate and the hook device housing can ensure that the optical voltage sensor does not move during the measurement process, thereby ensuring the accuracy of the measurement result;

[0018] (3) The hook device provided by the present invention has a shell of a stainless steel semi-enclosed structure with one side open, and the hook device shell and the GIS shell flange are connected to each other at the same potential, which can effectively shield the electromagnetic interference in the substation;

[0019] (4) The hooking device provided by the present invention fixes the hooking device shell to the GIS shell flange through bolts and connecting plates, which has the advantages of easy loading and unloading and the ability to change the position of the measuring point as needed, and is suitable for promotion and use in this field. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the installation of the optical voltage sensor hanging device and the GIS pot-type insulator in Example 1 of the present invention.

[0021] Figure 2 for Figure 1 Enlarged view of part A.

[0022] Figure 3 for Figure 2 Side view of.

[0023] Figure 4 This is a schematic diagram of the installation of the optical voltage sensor hanging device and the GIS pot-type insulator in Example 2 of the present invention.

[0024] Figure 5 This is a schematic diagram of the installation of the optical voltage sensor hanging device and the GIS pot-type insulator in Example 3 of the present invention.

[0025] In the figure, 1-hook device housing, 2-first bolt, 3-connecting plate, 3-1-slot hole, 4-bracket, 5-pressure plate, 6-optical fiber flange, 7-pot insulator, 8-second bolt, 9-GIS housing flange, 10-optical voltage sensor, 11-grounding flat steel, 12-casting hole. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0027] Example 1

[0028] This embodiment takes the optical voltage sensor hanging device applied to the single-pole single-box GIS equipment with open pot insulator as an example to explain in detail the hanging device structure and use method provided by the present invention. In the open pot insulator environment, the main structures affecting the measurement include the GIS pot insulator 7, the GIS shell flange 9 located on both sides of the edge of the pot insulator 7, and a number of second bolts 8 evenly arranged along its annular surface for connecting the GIS shell flange 9 on both sides of the edge of the pot insulator 7. The GIS shell flange is usually provided with a grounding flat steel 11, which is fixed to the GIS shell flange 9 by the second bolt 8 and the matching nut.

[0029] like Figures 1 to 3 As shown, the optical voltage sensor mounting device for GIS bus voltage measurement provided in this embodiment includes a mounting device housing 1, a matching sensor bracket 4 and a pressure plate 5 arranged in the mounting device housing and used to set up the optical voltage sensor, an optical fiber flange 6 arranged on the mounting device housing and used in conjunction with the optical voltage sensor, and a connecting plate 3 for fixing the mounting device housing 1 to the GIS housing flange 9.

[0030] like Figure 2 As shown, the housing 1 of the hooking device is a stainless steel rectangular box with one side open, and the open surface is tightly fitted with the surface of the pot insulator and the GIS housing flange 9. A pair of contact edges of the open surface are designed as straight lines, which are parallel to the width direction of the GIS pot insulator, and whose length is slightly larger than the width of the outer surface of the GIS pot insulator and slightly smaller than the distance between the edges of the housing flanges on both sides of the GIS pot insulator; the other pair of contact edges are designed as arcs, and their curvature is the same as that of the outer surface of the GIS pot insulator.

[0031] like Figure 2 and Figure 3 As shown, there are two brackets 4 and two pressure plates 5, which are symmetrically distributed at the center of the bottom surface of the hook device housing, and the distance between the two is less than the length or width of the optical voltage sensor. The design height of the bracket 4 needs to be determined according to the depth of the hook device housing and the curvature of the outer surface of the GIS pot-type insulator. In this embodiment, the gap between the optical voltage sensor and the outer surface of the GIS pot-type insulator is within 1 cm, so that the optical voltage sensor is as close to the outer surface of the GIS pot-type insulator as possible without contact, and the distance between the optical voltage sensor and the inner wall of the hook device housing is about 3 to 5 cm, so that the electric field strength around the sensor is large enough, continuous, and not distorted. The bracket 4 is a frame-type structure, and screw holes that cooperate with fastening screws are designed on the upper and lower end faces to achieve the fixation of the bracket to the housing, and the bracket to the pressure plate.

[0032] like Figure 2 and Figure 3As shown, the length of the pressing plate 5 matches the length of the bracket, and the pressing plate is provided with screw holes corresponding to the positions of the bracket. The optical voltage sensor 10 is placed on the bracket 4, and then the pressing plate 5 is connected to the bracket 4 by tightening screws to achieve crimping fixation of the sensor.

[0033] In order to prevent the electric field distribution around the sensor from being distorted, the bracket, pressure plate and fastening screws are all made of polytetrafluoroethylene with a small relative dielectric constant.

[0034] like Figure 2 and Figure 3 As shown, two fiber optic flanges 6 are provided at the bottom of the hook device housing 1, and the inward interfaces of the two fiber optic flanges 6 are respectively connected to the input and output fiber optic interfaces of the optical voltage sensor 10, and the outward interfaces are connected to the transmission fiber optic interface. The input and output optical fibers of the optical voltage sensor 10 are led out to the outside of the hook device through the two fiber optic flanges 6, so that the optical voltage sensor 10 is connected to its matching laser source and light detector to achieve the measurement of the GIS bus voltage.

[0035] like Figure 2 As shown, there are four connecting plates, which are divided into two groups and are located on both sides of the hooking device housing 1. The two connecting plates on each side are connected with the first bolt 2 and the second bolt 8 on the same side, so that the hooking device housing is fixed on the GIS housing. There are four first bolts 2, which are divided into two groups and are symmetrically arranged on both sides of the hooking device housing. The position of the first bolt on the hooking device housing should cooperate with the second bolt 8 and the connecting plate 3, so that the opening surface of the hooking device housing is tightly fitted with the surface of the pot insulator and the GIS housing flange. There are two second bolts 8, which penetrate the pot insulator and the GIS housing flange and are fastened to the housing flange by the original nuts. Both ends of the bolts protrude about 2 cm and are threaded. The diameters of the first bolt 2 and the second bolt 8 are equal. The length of the first bolts on both sides ensures that the sum of the width of the first bolt and the hooking device housing is equal to the length of the second bolt 8. The connecting plate is made of flat steel, and a slot 3-1 is designed on the connecting plate 3. The width of the connecting plate slot is equal to the diameter of the first bolt and the second bolt, so that the first bolt 2 and the second bolt 8 can be inserted therein, and the length thereof is appropriately larger than the spacing between the first bolt 2 and the corresponding second bolt 8. The connecting plate and the GIS shell flange 9, and the connecting plate and the hanging device shell are connected and fixed by tightening the nut, thereby achieving the purpose of fixing the hanging device shell and the GIS shell flange and equipotential connection.

[0036] The installation method of the above-mentioned hanging device is as follows: first, the bracket 4 is fixed to the bottom of the hanging device shell by fastening screws, and then the optical voltage sensor 10 is crimped onto the bracket 4 by the pressure plate 5 and the fastening screws, and the input and output optical fibers of the sensor are respectively connected to the two optical fiber flanges, and then the hanging device shell is placed on the outer surface of the basin insulator and fit, and the hanging device shell is fixed to the GIS shell by using the connecting plate 3, the first bolt 2, the second bolt 8 and the matching nut.

[0037] The above-mentioned hooking device is more suitable for indoor GIS equipment. In order to be applied to outdoor GIS equipment, it is necessary to perform waterproof sealing treatment on the contact edges between the hooking device housing and the pot-type insulator and the GIS housing.

[0038] For the single-pole single-box GIS equipment with an open pot-type insulator in this embodiment, the hanging device can be installed at any position on the outer surface of the pot-type insulator. For the convenience of installation, the position where the grounding flat steel 11 is located can be avoided.

[0039] Example 2

[0040] This embodiment is aimed at a three-pole common box GIS device with an open pot-type insulator. The outer surface of the pot-type insulator and its surrounding structure are the same as those of the single-pole single-box GIS device in Example 1. In order to measure the GIS bus voltage of this type of equipment, three optical voltage sensor mounting devices for GIS bus voltage measurement are required, such as Figure 4 As shown, the three hanging devices are respectively located at positions a, b, and c on the surface of the pot insulator closest to the A, B, and C three-phase busbars.

[0041] The structure of the hooking device in this embodiment is the same as that of the hooking device given in Embodiment 1, and will not be described again here.

[0042] The above three devices are respectively located at a, b, and c. The method of hanging will cause each sensor to receive a composite signal, which includes the signals coupled from the other two non-measurement phases. In order to obtain the real voltage of the measurement phase, this composite signal needs to be decoupled and processed. For the specific processing method, please refer to the application document with application number CN201010209837.9.

[0043] Through the hooking device provided in this embodiment, the application of the optical voltage sensor in the bus voltage measurement of the three-pole common box GIS is realized for the first time.

[0044] Example 3

[0045] This embodiment is directed to a single-pole single-box GIS device with a metal ring pot insulator. The metal ring wraps the outer circumferential surface of the pot insulator. The metal ring is designed with a pot insulator pouring hole 12. The pouring hole 12 of the original GIS device is covered with an iron sheet. Before installing the hanging device, the iron sheet is removed. A number of second bolts 8 are evenly arranged along the ring surface of the metal ring, but their positions do not overlap with the pouring hole, so they do not affect the measurement.

[0046] The structure of the hooking device used in this embodiment is the same as the structure of the hooking device given in Embodiment 1, and will not be described in detail here.

[0047] The hanging device is installed outside the pouring hole of the pot insulator. Since the pouring hole is small, the electric field signal on the surface of the pot insulator with metal ring will be much smaller than that of the open pot insulator, so it is necessary to properly adjust the height of the sensor bracket 4 to make the sensor closer to the surface of the pot insulator. In the preferred implementation, the gap between the optical voltage sensor and the outer surface of the GIS pot insulator is within 0.5 cm.

[0048] Those skilled in the art will appreciate that the embodiments described herein are intended to help readers understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations that do not deviate from the essence of the present invention based on the technical revelations disclosed by the present invention, and these variations and combinations are still within the protection scope of the present invention.

Claims

1. An optical voltage sensor mounting device for GIS bus voltage measurement, characterized in that The invention comprises a hook device housing (1), a matching sensor bracket (4) and a pressure plate (5) arranged in the hook device housing and used to set up an optical voltage sensor, an optical fiber flange (6) arranged on the hook device housing and used in conjunction with the optical voltage sensor, and a connecting plate (3) for fixing the hook device housing (1) to a GIS housing flange (9); the hook device housing is designed with an opening surface that fits with a basin insulator and a GIS housing flange; the bracket (4) and the pressure plate (5) are both two in number, and the brackets are symmetrically distributed at the center of the bottom surface of the hook device housing, with the two brackets spaced 1 / 4 from each other. The distance is smaller than the length or width of the optical voltage sensor, and the optical voltage sensor is crimped and fixed to the bracket by adjusting the fastening screws at both ends of the pressure plate; a slot (3-1) is designed on the connecting plate (3), and a first bolt (2) arranged on the outer side of the hanging device shell and a second bolt (8) on the pot-type insulator and the GIS shell flange are fixed in the connecting plate slot through a matching nut, so that the hanging shell and the GIS shell are connected to the same potential; the connecting plate (3) is made of flat steel; the bracket (4), the pressure plate (5) and the fastening screws used to fix the bracket and the pressure plate are all made of insulating materials.

2. The optical voltage sensor mounting device for GIS bus voltage measurement according to claim 1 is characterized in that The opening surface of the hanging device housing (1) is designed with an arc-shaped contact edge that matches the curvature of the outer surface of the GIS pot-type insulator.

3. The optical voltage sensor mounting device for GIS bus voltage measurement according to claim 1 or 2, characterized in that The design height of the bracket (4) ensures that the gap between the optical voltage sensor and the outer surface of the GIS pot-type insulator is within 1 cm.

4. The optical voltage sensor mounting device for GIS bus voltage measurement according to claim 1 is characterized in that There are two optical fiber flanges (6), the inward interfaces of the two optical fiber flanges are respectively connected to the input and output optical fiber interfaces of the optical voltage sensor, and the outward interfaces are connected to the transmission optical fiber interface.

5. The optical voltage sensor mounting device for GIS bus voltage measurement according to claim 1 is characterized in that The first bolt (2) and the second bolt (8) have the same diameter.

6. The optical voltage sensor mounting device for GIS bus voltage measurement according to claim 5 is characterized in that The width of the connecting plate slot is equal to the diameter of the first bolt and the second bolt.

7. The optical voltage sensor mounting device for GIS bus voltage measurement according to claim 1 is characterized in that When the hanging device is applied to a single-pole single-box GIS device with an open pot-type insulator, the hanging device is hung at any position on the outer surface of the pot-type insulator; when the hanging device is applied to a three-pole common-box GIS device with an open pot-type insulator, a hanging device is placed at each position on the surface of the pot-type insulator closest to the three-phase busbar; when the hanging device is applied to a single-pole single-box GIS device with a metal ring pot-type insulator, the hanging device is hung at the casting hole of the pot-type insulator.

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