CN104459491A - Arc sensor for partial discharge detection of high-voltage conductors in GIS - Google Patents
Arc sensor for partial discharge detection of high-voltage conductors in GIS Download PDFInfo
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- CN104459491A CN104459491A CN201410764932.3A CN201410764932A CN104459491A CN 104459491 A CN104459491 A CN 104459491A CN 201410764932 A CN201410764932 A CN 201410764932A CN 104459491 A CN104459491 A CN 104459491A
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Abstract
The invention discloses an arc sensor for partial discharge detection of high-voltage conductors in a GIS. The arc sensor comprises an insulator and three auxiliary electrodes corresponding to the three-phase high-voltage conductors. The insulator is provided with a metal flange. The three auxiliary electrodes are of a circular arc shape and of the same structure. The three auxiliary electrodes are distributed on the circumference of the same circle. The three auxiliary electrodes and the insulator are concentric. The auxiliary electrodes are formed in epoxy resin of the insulator in a pouring mode, and the auxiliary electrodes and the insulator are integrated. After the high-voltage conductors are arranged in the insulator in a sleeved mode, the auxiliary electrodes are also arranged on the outer sides of the high-voltage conductors in a sleeving mode. The two ends of each auxiliary electrode are each provided with a terminal, wherein one terminal is a grounding terminal, and the other terminal is a detection terminal; the detection terminal stretches out of the insulator and is used for being connected with a detection device. The arc sensor can detect electromagnetic waves generated during partial discharge of the high-voltage conductors in the GIS and is high in ante-interference capability and detection sensitivity.
Description
Technical field
The present invention relates to the checkout equipment of electrical equipment in electric system, specifically refer to GIS internal high voltage conductor Partial Discharge Detection arc sensor.
Background technology
Because reliability is high, the advantages such as superior performance are widely used in electric system gas isolated metal closed combined electrical appliance (gas-insulated metal-enclosed switchgear is called for short GIS).But when insulation fault occurs GIS, its servicing time is long, and influence area is large, and consequence is serious.The insulation diagnosis of GIS is mainly reflected in the detection of shelf depreciation.The structure of SF6 and equipment has a certain impact for the characteristic of shelf depreciation.The current impulse produced can reach nanometer scale, causes electromagnetic wave in the propagation of the scope of Gigahertz.Thus, the sensor detected for GIS partial discharge needs to have sufficiently high sensitivity and good frequency response characteristic.
GIS generally can be divided into single-phase single-cylinder type and three-phase cartridge type two kinds of forms altogether.Three-phase element and conductor are arranged by " product " font and are concentrated in a larger cylinder by three-phase altogether cartridge type, make phase insulation make full use of the superior insulating property of SF6 gas.Compare the structure of single-phase single-cylinder type, it is little that it has overall volume, installs, maintenance is convenient, the advantage such as to save time.At present, 110KV electric pressure and bus can make three-phase cartridge type altogether, 220KV and the single-phase single-cylinder type of above more employing.The present invention designs a kind of Novel built-in type local discharge sensor being total to cartridge type for three-phase.
Be devoted to the research that GIS partial discharge detects both at home and abroad, many traditional measurement of partial discharge sensors are developed out, but its security, sensitivity etc. are lower, and expensive, should not promote always.Due to the complicacy of technology and technical requirement very high, its skill level is ripe not enough, and there are problems needs to solve.
GIS partial discharge sensing mainly contains built-in sensing and external sensing two kinds of modes.External sensing mode is particularly suitable for the GIS manufactured, but its sensitivity is lower, and can run into relatively larger spatial electromagnetic interference, and the outer sensor of research at present mainly contains type UHF sensor, biconical antenna and slot antenna etc.Built-in sensing mode has highly sensitive, that antijamming capability is strong outstanding advantages, and the built-in sensors of research at present mainly contains plate shaped sensor, cone-shaped sensor and disc sensor.
University Of Chongqing is for GIS structure and inner shelf depreciation feature, laboratory GIS analogue means devises a kind of built-in circular loop antenna of structure innovation, and theoretical analysis and actual measurement are carried out to its response characteristic: the frequency response characteristic adopting square-wave response analyte sensors and whole test macro from capacitive coupling principle angle, from antenna model angle analysis amplitude-frequency response characteristic.
Some researchs in past show, the disc insulator of GIS all cover by metal outer ring, thus the electromagnetic wave that the middle shelf depreciation of GIS produces has quite a few, thus seriously hinders UHF signal to external leakage, greatly reduces the sensitivity of external detection method.In addition, external sensor chi footpath is large, and be subject to spatial electromagnetic interference, effect is not good at the scene.
Because the Earlier designs of GIS technology does not provide extra arrangement space, traditional built-in sensor needs to increase on original housing to arrange window to carry out the installation of sensor.Therefore, sensor can only receive the signal leaked by installing window, and its monitoring range and sensitivity are subject to dropping to restriction; And extra installing space easily causes GIS poorly sealed, causes the leakage of SF6 gas; The increase of window and sensor also makes GIS cost greatly improve.In addition, because the increase of window and sensor becomes uneven, insulation margin can be reduced, the safe reliability that GIS runs can not be ensured at GIS original coaxial configuration uniform electric field.Although the window that the circular loop antenna of University Of Chongqing need not be extra is arranged, the antenna of its open loop structure also also exists installs the problems such as difficult, installation cost is high, can not drop into Site Detection application.
In order to address these problems, need development of new sensor, make sensor when mounted without the need to removing the encapsulation of GIS and degassed, also can not destroy original Electric Field Distribution; While its security of guarantee and sensitivity, reduce the cost and risk that it is installed and used as far as possible.
Summary of the invention
The object of this invention is to provide GIS internal high voltage conductor Partial Discharge Detection arc sensor, this sensor antijamming capability is strong and detection sensitivity is high.
Above-mentioned purpose of the present invention realizes by following technical solution: GIS internal high voltage conductor Partial Discharge Detection arc sensor, it is characterized in that: described arc sensor comprises insulator and corresponds to three sections of auxiliary electrodes of three-phase high-voltage conductor, described insulator has metal flange, three sections of described auxiliary electrodes are the circular arc that structure is identical, three sections of auxiliary electrodes are distributed in same circle circumferentially, and it is concentric with described insulator, described auxiliary electrode is cast in the epoxy inner of insulator, become one with insulator, after insulator suit high-pressure conductor, described auxiliary electrode is also placed on the outside of high-pressure conductor, the two ends of every section of auxiliary electrode all have a terminal, one of them terminal is ground terminal, for ground connection after being connected with metal flange, another terminal is detection terminal, described detection terminal stretches out outside insulator, for being connected with pick-up unit, described circular arc sensor can detect the electromagnetic wave that GIS internal high voltage conductor shelf depreciation produces, and the electromagnetic wave detected is flowed to pick-up unit, thus judge whether GIS internal high voltage conductor exists shelf depreciation.
In the present invention, described insulator is disc insulator.
In the present invention, described ground terminal is earthing screw.
In the present invention, described detection terminal is for detecting screw.
In the present invention, the material of described ground terminal, detection terminal is aluminium.
Detection terminal of the present invention is connected with pick-up unit by lead-in wire, and its diameter is relatively thick, to reduce its impedance, reduces the impact on measurement result.
The circular arc auxiliary electrode that the present invention is cast in casting epoxide resin material is connected with the shell of ground connection by screw, and its fundamental purpose balances and the distribution of UNIFORM ELECTROSTATIC FIELD and the insulation effect of clearance that may exist between the epoxy resin insulation material of elimination and aluminium flange joint.There is an acceptance point that can be used to collection signal each arc-shaped electrode one end, can be connected, thus reach measurement object as one section of antenna by lead-in wire with pick-up unit.
Insulator in the present invention is vertically set in the grounding shell of GIS, the electrode of sensor is arranged to circular arc and is cast in the epoxy inner of insulator, simultaneously, columniform high-pressure conductor arranges along grounding shell axis and passes insulator, and the sensor in this structure can expand monitoring area; The motor of sensor is circular arc, can effectively even field intensity, avoids wedge angle to produce electric field intensity sudden change; The position of sensor be in insulator earth potential side and with grounding shell metal short circuit, designed shape and position calculate through refined analysis, can improve the electric field intensity at this place, improve GIS original insulation margin; Radome is set in the both sides of insulator and can improves the electric field intensity at this place of insulator and the coupling bolt shielded within the scope of its encirclement, prevent that electric field intensity is uneven causes insulation fault.
Compared with prior art, sensor of the present invention has following remarkable result:
(1) safe reliability is high.What this sensor adopted is wireless working method, avoids the impact of wiring on GIS built-in electrical insulation; Sensor utilizes the electromagnetic wave signal energy supply received, and does not need additionally to provide power supply, avoid GIS inside get can difficulty and power supply be arranged on the potential safety hazard that causes of GIS inside.
(2) antijamming capability is strong.This sensor can receive the signal of superfrequency frequency band, shows that its anti-electromagnetic interference capability is strong, normally can work in the electromagnetic environment of complexity through on-the-spot test.
(3) receiving sensitivity is high.Compare traditional external and built-in sensor, and pure hoop antenna, there is higher sensitivity.
(4) be not only often used as receiving antenna at hyper band, also can receive the signal of some strength in low-frequency range.
(5) sensor of the present invention be embedded in insulator, installing space that need not be extra, cost is low, and stability is high, and does not need the energy supply of sensor side, easy to maintenance.Arc structure compares pure cirque structure more simple and flexible, and can save certain cost can reduce a large amount of material resources, financial resources and manpower for kiowatt, increases economic efficiency, and ensures the security of operation of power equipment.This all will agree with and serve the strong intelligent grid great strategy of unification that current China grid company implements.
Accompanying drawing explanation
Below in conjunction with the drawings and specific embodiments, the present invention is described in further details.
Fig. 1 is the cut-away view of GIS, the position of display internal high voltage conductor, insulator and shell;
Fig. 2 is the structural representation of arc sensor of the present invention;
Fig. 3 is the frequency spectrum wave figure of the 20pC discharge signal that existing external sensor detects, measurement be point discharge signal on bus;
Fig. 4 is the frequency spectrum wave figure of the 20pC discharge signal that existing built-in sensor detects, measurement be point discharge signal on bus;
Fig. 5 is the frequency spectrum wave figure of the 20pC discharge signal that sensor of the present invention detects, measurement be point discharge signal on bus.
Description of reference numerals
1, high-pressure conductor; 2, insulator; 21, metal flange; 3, shell;
4, auxiliary electrode; 41, ground terminal; 42, detection terminal
Embodiment
As Fig. 1, GIS internal high voltage conductor Partial Discharge Detection arc sensor shown in Fig. 2, this arc sensor comprises insulator 2 and corresponds to three sections of auxiliary electrodes 4 of three-phase high-voltage conductor 1, insulator 2 is disc insulator 2, insulator 2 has metal flange 21, three sections of auxiliary electrodes 4 are the circular arc that structure is identical, three sections of auxiliary electrodes 4 are distributed in same circle circumferentially, and it is concentric with insulator 2, auxiliary electrode 4 is cast in the epoxy inner of insulator 2, become one with insulator 2, after insulator 2 is set with high-pressure conductor 1, auxiliary electrode 4 is also placed on the outside of high-pressure conductor 1, the two ends of every section of auxiliary electrode 4 all have a terminal, one of them terminal is ground terminal 41, for ground connection after being connected with metal flange 21, be connected with the shell 3 of the GIS of ground connection after being specifically connected with metal flange 21, reach the effect of ground connection, another terminal is detection terminal 42, detection terminal 42 stretches out outside insulator 2, do not contact with metal flange 21, detection terminal 42 is for being connected with pick-up unit, circular arc sensor can detect the electromagnetic wave that GIS internal high voltage conductor 1 shelf depreciation produces, and the electromagnetic wave detected is flowed to pick-up unit, thus judge whether GIS internal high voltage conductor 1 exists shelf depreciation.Here pick-up unit is the external oscillograph be connected with detection terminal 42 by wire.
High-pressure conductor 1 in the present embodiment comprises the internal part such as isolating switch, bus, disconnector of GIS inside, and arc sensor of the present invention can measure the ultrahigh frequency electromagnetic wave signal of the point discharge, bubble electric discharge, metallic particles electric discharge, creeping discharge, bubble electric discharge etc. of GIS device inside.
In the present embodiment, three-phase high-voltage conductor 1 is enclosed in a circular cylindrical chamber, adopts Threephase common-box structure.Its advantage is that shell eddy current loss is little, and correspondingly current-carrying capacity is large.High-pressure conductor 1 basin shape insulator is fixed, and the conductor part cover of insulator both sides has grading ring, to avoid electric discharge.
In the present embodiment, ground terminal 41 is earthing screw, and detection terminal 42 is for detecting screw, and the material of ground terminal 41, detection terminal 42 is aluminium.Due to the expansion coefficient of aluminium and the epoxy expansion coefficient similar of insulator, so be aluminium by the material selection of two terminals.
Arc sensor of the present invention is built-in built-in type circular arc sensor, sensor and insulator 2 integrated as a whole, the vitals of sensor is as inner in auxiliary electrode 4 is cast in GIS disc insulator 2, for detecting the shelf depreciation electromagnetic wave signal on the high-pressure conductor 1 that transmits in GIS cavity, solve that traditional sensors is arranged on the installation site problem of GIS inside, field intensity is uniformly distributed problem and sensitivity problem.For a large amount of material resources, financial resources and manpower have been saved in electric system, stop due to sensor wiring or got the potential safety hazard that can cause, having improve the safe reliability of Operation of Electric Systems.
The unique texture of circular arc type sensor of the present invention determines its built-in sensor comparing other types and is coupled to more wide band signal, its earthing screw part is equivalent to unipole antenna, may be used for couples high frequency signals, circular arc shaped portion then can be coupled to certain low frequency signal.
Sensor of the present invention, when carrying out experiment test, installs spine discharging model on high-pressure conductor 1 surface.Produce shelf depreciation when being 21kV by power frequency experimental transformer to the trial voltage that spine discharging model applies, shelf depreciation instrument display Apparent discharge magnitude is about 20pC, and sensor of the present invention receives local discharge signal, presents waveform by oscillograph.
Fig. 3, Fig. 4, Fig. 5 are the spectrum waveforms adopting the 20pC discharge signal that each checkout equipment and sensor of the present invention detect in prior art, and the position of measurement is the point discharge signal on GIS internal bus.Wherein, Fig. 3 is the waveform that external sensor measures, and Fig. 4 is the waveform that existing built-in sensor measures, and Fig. 5 is the waveform that sensor of the present invention measures.As can be seen from Fig., identical or equivalent locations place, the signal amplitude that the amplitude that the present invention detects arrives much larger than other three classes antenna detection.Compare with built-in sensors with external, the ability that the present invention detects shelf depreciation is stronger, reason may be that local discharge signal is many at the content of low frequency part, few at the content of HFS, and the present invention in the detectability of low frequency part higher than other a few class sensors.The present invention effectively can monitor GIS inside cavity local discharge signal, and its sensitivity, precision and signal intensity all meet the design of expection.
The above embodiment of the present invention is not limiting the scope of the present invention; embodiments of the present invention are not limited thereto; all this kind is according to foregoing of the present invention; according to ordinary technical knowledge and the customary means of this area; do not departing under the present invention's above-mentioned basic fundamental thought prerequisite; to the amendment of other various ways that said structure of the present invention is made, replacement or change, all should drop within protection scope of the present invention.
Claims (5)
1.GIS internal high voltage conductor Partial Discharge Detection arc sensor, it is characterized in that: described arc sensor comprises insulator and corresponds to three sections of auxiliary electrodes of three-phase high-voltage conductor, described insulator has metal flange, three sections of described auxiliary electrodes are the circular arc that structure is identical, three sections of auxiliary electrodes are distributed in same circle circumferentially, and it is concentric with described insulator, described auxiliary electrode is cast in the epoxy inner of insulator, become one with insulator, after insulator suit high-pressure conductor, described auxiliary electrode is also placed on the outside of high-pressure conductor, the two ends of every section of auxiliary electrode all have a terminal, one of them terminal is ground terminal, for ground connection after being connected with metal flange, another terminal is detection terminal, described detection terminal stretches out outside insulator, for being connected with pick-up unit, described circular arc sensor can detect the electromagnetic wave that GIS internal high voltage conductor shelf depreciation produces, and the electromagnetic wave detected is flowed to pick-up unit, thus judge whether GIS internal high voltage conductor exists shelf depreciation.
2. GIS internal high voltage conductor Partial Discharge Detection arc sensor according to claim 1, is characterized in that: described insulator is disc insulator.
3. GIS internal high voltage conductor Partial Discharge Detection arc sensor according to claim 1, is characterized in that: described ground terminal is earthing screw.
4. GIS internal high voltage conductor Partial Discharge Detection arc sensor according to claim 1, is characterized in that: described detection terminal is for detecting screw.
5. GIS internal high voltage conductor Partial Discharge Detection arc sensor according to claim 1, is characterized in that: the material of described ground terminal, detection terminal is aluminium.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410764932.3A CN104459491A (en) | 2014-12-11 | 2014-12-11 | Arc sensor for partial discharge detection of high-voltage conductors in GIS |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201410764932.3A CN104459491A (en) | 2014-12-11 | 2014-12-11 | Arc sensor for partial discharge detection of high-voltage conductors in GIS |
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| CN104459491A true CN104459491A (en) | 2015-03-25 |
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| CN201410764932.3A Pending CN104459491A (en) | 2014-12-11 | 2014-12-11 | Arc sensor for partial discharge detection of high-voltage conductors in GIS |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105676087A (en) * | 2016-02-02 | 2016-06-15 | 国家电网公司 | Sensing system for detecting ultrahigh-frequency partial discharging of GIS pouring hole |
| CN110581358A (en) * | 2019-09-21 | 2019-12-17 | 华北电力大学（保定） | hollow arc antenna internally arranged in GIS basin-type insulator and design method thereof |
| CN113433430A (en) * | 2021-05-19 | 2021-09-24 | 深圳供电局有限公司 | Partial discharge detection apparatus and method |
| CN113851282A (en) * | 2021-11-09 | 2021-12-28 | 南方电网科学研究院有限责任公司 | GIS basin-type insulator surface charge shielding device |
| CN115032512A (en) * | 2022-08-15 | 2022-09-09 | 国网天津市电力公司电力科学研究院 | GIS basin-type insulator on-line detection sensor |
| CN116973711A (en) * | 2023-08-30 | 2023-10-31 | 武汉朗德电气有限公司 | Auxiliary installation device of GIS partial discharge sensor |
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| CN204359899U (en) * | 2014-12-11 | 2015-05-27 | 广东电网有限责任公司电力科学研究院 | GIS internal high voltage conductor Partial Discharge Detection arc sensor |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105676087A (en) * | 2016-02-02 | 2016-06-15 | 国家电网公司 | Sensing system for detecting ultrahigh-frequency partial discharging of GIS pouring hole |
| CN110581358A (en) * | 2019-09-21 | 2019-12-17 | 华北电力大学（保定） | hollow arc antenna internally arranged in GIS basin-type insulator and design method thereof |
| CN113433430A (en) * | 2021-05-19 | 2021-09-24 | 深圳供电局有限公司 | Partial discharge detection apparatus and method |
| CN113851282A (en) * | 2021-11-09 | 2021-12-28 | 南方电网科学研究院有限责任公司 | GIS basin-type insulator surface charge shielding device |
| CN113851282B (en) * | 2021-11-09 | 2024-01-09 | 南方电网科学研究院有限责任公司 | GIS basin-type insulator surface charge shielding device |
| CN115032512A (en) * | 2022-08-15 | 2022-09-09 | 国网天津市电力公司电力科学研究院 | GIS basin-type insulator on-line detection sensor |
| CN115032512B (en) * | 2022-08-15 | 2022-10-28 | 国网天津市电力公司电力科学研究院 | GIS basin-type insulator on-line detection sensor |
| CN116973711A (en) * | 2023-08-30 | 2023-10-31 | 武汉朗德电气有限公司 | Auxiliary installation device of GIS partial discharge sensor |
| CN116973711B (en) * | 2023-08-30 | 2024-03-19 | 武汉朗德电气有限公司 | Auxiliary installation device of GIS partial discharge sensor |
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