CN1115566C - Partial discharge detector of gas-insulated apparatus - Google Patents

Partial discharge detector of gas-insulated apparatus Download PDF

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Publication number
CN1115566C
CN1115566C CN 97182201 CN97182201A CN1115566C CN 1115566 C CN1115566 C CN 1115566C CN 97182201 CN97182201 CN 97182201 CN 97182201 A CN97182201 A CN 97182201A CN 1115566 C CN1115566 C CN 1115566C
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China
Prior art keywords
partial discharge
air insulating
mentioned
detecting device
discharge detecting
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Expired - Lifetime
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CN 97182201
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CN1254416A (en
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加藤达朗
大下阳一
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Hitachi Ltd
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Hitachi Ltd
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Abstract

A compact antenna with a wide band and high sensitivity is used for detecting an electromagnetic wave caused by partial discharge which occurs in the interior abnormality of gas-insulated equipment. Two semicircular boards in a metal container 3 of the gas-insulated equipment are assembled on a plane to form a circular antenna receiving part 4 which is utilized to use the wide band and the high sensitivity to detect the electromagnetic wave with the partial electricity. Detected signals pass through a coaxial seal terminal 7 and a coaxial cable 8 and are measured by a measuring device 10. In addition, because the antenna receiving part of the semicircular boards is made to have a large area, the electric capacity between the antenna receiving part and an electric potential measuring part can be increased; accordingly, electric potentials can be measured with high sensitivity.

Description

The partial discharge detecting device of air insulating device
Technical field
The present invention relates to the partial discharge detecting device of air insulating device, relating to that the utmost point is suitable in filling air insulating devices such as gas-break switch that insulating gas uses, gas-insulated switchgear device, gas insulated bus from the inner Abnormal Insulation that takes place of canister external detection canister is the partial discharge signal supervisory instrument of partial discharge.
Background technology
As at the employed power equipment of power transformation, gas-insulated switchgear device, gas insulated bus, gas-insulated transformer etc. are arranged.These power equipments are air insulating devices that high-voltage conductor has been supported on insulation ground in having filled the airtight canister of insulating gas, when having inherent vice such as metallic foreign body, will form high electric field partly, thus the generation partial discharge.If the partial discharge that takes place is tossed aside, will cause insulation breakdown, thereby might cause big accident.Therefore, must early detection such in the inner partial discharge that takes place of canister and take certain countermeasure.Can predict insulation breakdown by the test section discharge signal, this is known to everybody in advance, and the test section discharge comes into one's own as the method for preventing and protecting of air insulating device.
Yet, SF 6Partial discharge in the gas is the high-tension phenomena that the pulse current of point takes place, and the electromagnetic wave that is taken place by partial discharge is propagated in canister instantaneously to space radiation.Therefore, can predict Abnormal Insulation by detecting this electromagnetic wave, but, owing to be closed container, electromagnetic wave hardly can be from the canister internal radiation to the outside, so, proposed at the inner detection signal of closed container, used the partial discharge detecting device of the air insulating device that airtight terminal detects by the measurement mechanism of outside.
For example, known method has, as Japanese kokai publication hei 3-56016 communique is described, in the canister of air insulating device, tours antenna is set, detect the electromagnetic method of the partial discharge radiation that takes place by this tours antenna, and as Japanese kokai publication hei 3-164023 communique is described, the method that detects with slot aerial from the canister outside.
In addition, for air insulating device, in checking that running voltage determination that whether has added normal voltage and the surge voltage of checking thunder and lightning or switch surge are measured,, also need voltage check device in order to detect voltage.As the detection method of the noncontact mode of this voltage determination, the known method that the described such static partial-pressure of Japanese kokai publication hei 8-248065 communique is arranged.
The partial discharge detection method of the air insulating device that has earlier is exactly above-described method, but, the partial discharge signal is very faint, owing to be subjected to the influence of external noise, the detection sensitivity of partial discharge signal differs and satisfies needed precision surely, so, expect to have more highly sensitive partial discharge detection method.In addition, the position that partial discharge takes place not simultaneously, not only the size of signal but also the output of each frequency also may differ widely.In order to demarcate the position that partial discharge takes place, requiring all has very high detection sensitivity in the very wide frequency band of 0~number GHz.
In addition, in voltage determination, in order to carry out correct mensuration, the determinator maximization that becomes, thereby need simply and correctly method for measuring.
The 1st purpose of the present invention aims to provide the partial discharge detecting device of broadband, highly sensitive air insulating device.
The 2nd purpose of the present invention aims to provide the partial discharge detecting device of the air insulating device that can measure running voltage and surge voltage.
The 3rd purpose of the present invention aims to provide broadband, high sensitivity, can measure the partial discharge detecting device of the air insulating device of running voltage and surge voltage.
Disclosure of an invention
In order to achieve the above object, the invention provides a kind of partial discharge detecting device that is used to have the canister of enclosing insulating gas and wherein comprises the air insulating device of the high-voltage conductor of supporting by insulation supporter, comprising: the signal receiving antenna portion that in above-mentioned canister, is provided with; What be connected with this signal receiving antenna portion passes through the concentric cable that coaxial hermetic terminal electrically is drawn out to above-mentioned canister outside; And the determinator that is connected with this concentric cable, it is characterized in that: signal receiving antenna has been set to a gap by 2 tabular conductive electrodes of semicircle and has relatively formed, and represents heart yearn and the outside line of the signal wire of this concentric cable to be connected with arbitrary electrode in the 2 tabular conductive electrodes of semicircle on every side of this gap of the round center that forms thus respectively.
The simple declaration of accompanying drawing
Fig. 1 is the longitudinal diagram of partial discharge detecting device of the air insulating device of expression one embodiment of the present of invention.
Fig. 2 is the longitudinal diagram that expression is applied to the example of gas isolated potential measurement.
Fig. 3 is the longitudinal diagram of the variation of presentation graphs 2.
Fig. 4 is the longitudinal diagram of the variation of presentation graphs 1.
Fig. 5 is the part longitudinal diagram of the variation of presentation graphs 1.
Fig. 6 is the longitudinal diagram of the variation of expression antenna acceptance division.
Fig. 7 is the longitudinal diagram of the variation of presentation graphs 2.
Fig. 8 is the longitudinal diagram that expression is provided with the example of reflecting plate.
The optimised form that carries out an invention
Below, with reference to Fig. 1~Fig. 8 one embodiment of the present of invention are described.Fig. 1 is the longitudinal diagram of the partial discharge detecting device of expression one embodiment of the present of invention, Fig. 2 is the longitudinal diagram that expression is applied to the example of gas isolated potential measurement, Fig. 3 is the longitudinal diagram of the variation of presentation graphs 2, Fig. 4 is the part longitudinal diagram of the variation of presentation graphs 1, Fig. 5 is the part longitudinal diagram of the variation of presentation graphs 1, Fig. 6 is the longitudinal diagram of the variation of expression antenna acceptance division, Fig. 7 is the longitudinal diagram of the variation of presentation graphs 2, and Fig. 8 is the longitudinal diagram that expression is provided with the example of reflecting plate.
Example shown in Figure 1, expression is applied to situation as a phase of the gas insulated bus of air insulating device called optical imaging with the partial discharge detecting device of present embodiment.The canister 3 that forms tubulose becomes earthing potential, and in this canister 3, high-voltage conductor 2 is supported by insulation supporter 1.In addition, in canister 3, enclose the SF of excellent insulation performance 6Deng insulating gas.On the housing section of canister 3, hand hole is set, in this hand hole, antenna acceptance division 4 is set.The flange 5 that is used to seal is set to hand hole.Antenna acceptance division 4 is configured to plane by the circular slab that 2 semicircular plates are combined into and constitutes.These 2 semicircular plates use copper or the aluminium as good conductor, form conductive electrode.Antenna acceptance division 4 is installed to the antenna that is fixed on the flange 5 and is arranged in the hand hole and supports on the platform 6.Therefore, antenna is fixed in the canister 3 as grounding container by the insulant electricity with floating.Support the central portion of platform 6 that the little concentric cable of impedance variation 8 is set at antenna.Antenna acceptance division 4 is connected with the heart yearn of coaxial terminal 2 semicircular plates near the center of circle respectively near it is provided with the position with out conductor, thereby is connected with concentric cable 8.Concentric cable 8 is connected with canister 3 concentric cable 8 outward by the coaxial hermetic terminal 7 that is arranged on the flange 5, and then is connected with determinator 10 by coaxial connector.
In the partial discharge detecting device of the air insulating device that constitutes like this, when in canister 3 partial discharge taking place, with the current impulse that takes place up to the high frequency of number GHz, electromagnetic wave is propagated in canister 3.When the electromagnetic wave of this propagation is received by antenna acceptance division 4, just on antenna acceptance division 4, induce voltage.The voltage of induction is by being installed in the outside that hermetic terminal 6 on the flange 5 outputs to canister 3, and sends determinator 10 to by concentric cable 8.Antenna acceptance division 4 as detecting device is that 2 semicircular plates are made up conglobate structure, it is the shape of area that increases the acceptance division of doublet antenna, increase the electric capacity between high-voltage conductor 2 and ground connection, thereby can measure the current potential in the air insulating device.In addition, by adopting the structure of coaxial configuration, can make the above signal of 100MHz of reception be sent to determinator unattenuatedly, thereby can be measured to the high frequency band of several GHz from antenna acceptance division transmission signal.In addition, owing to the space that holds antenna acceptance division 4 in canister 3 is restricted, so, by using such antenna acceptance division 4, in narrow space, just can receive wide band signal.
In addition, by antenna acceptance division 4 ground connection are used, antenna itself is used with earthing potential as floating electrode, thereby also can reduce the generation obstacle even be arranged on air insulating device inside.
Like this, just can the wide band partial discharge of high-sensitivity detection, not only can realize the prevention and maintain of high-precision air insulating device but also 1 wide ranges that antenna can detect in the air insulating device, so, a plurality of antennas needn't be set, thereby also be worthwhile economically.
In Fig. 2, Fig. 3, expressed the example of the potential measurement that is applicable to air insulating device.At this moment, do not use antenna to support platform, and support antenna acceptance division 4 with the coaxial circles bobbin.As shown in Figure 2, between antenna acceptance division 4 and high-voltage conductor 2, form capacitor C 1, between antenna acceptance division 4 and ground, form capacitor C 2.This capacitor C 1 and capacitor C 2 are the values that can measure in advance, can measure the current potential that passes through the electric capacity static partial-pressure with antenna acceptance division 4.According to the current potential of this mensuration, can be determined at voltage on the high-voltage conductor 2 by static partial-pressure.When measuring current potential by static partial-pressure, the big more sensitivity of electric capacity is high more.This enforcement is on the contrary by above-mentioned such antenna acceptance division 4 that constitutes, so, be applicable to the area big detecting device of acceptance division.
In addition, example shown in Figure 3 represents to be used for the structure example with higher sensitivity determination current potential.In this embodiment, the heart yearn of concentric cable 8 that is arranged on the outside of canister 3 is connected with out conductor, capacitor C3 is inserted between heart yearn and the ground.Be far longer than capacitor C 2 by the electric capacity that makes capacitor C3, promptly C2<<C3, just can carry out highly sensitive voltage determination.
When in air insulating device, using above-mentioned semicircular plate antenna, must consider because the situation of the concentrated insulation reduction that causes of electric field, so the position of setting has just become problem.Insulation reduction owing to preventing to cause owing to electric field is concentrated under the influence of this antenna is arranged on low electric field parts such as particle collector, absorbent container or hand hole, simultaneously, has carried out Fig. 4~research shown in Figure 6.
Example shown in Figure 4 forms fillet with the edge part of peripheral part that forms the semicircular plate of antenna acceptance division 4.By adopting such structure, can not reduce receiving sensitivity and prevent that electric field from concentrating.
Example shown in Figure 5 is that metal guarded electrode 16 as cover cap is arranged on the outside that antenna is supported platform 6, and this guarded electrode 16 forms to the center side bending, and will constitute the part covering of peripheral part of the semicircular plate of antenna acceptance division 4.Such structure can prevent that also electric field is concentrated.
Example shown in Figure 6 forms antenna acceptance division 4 and the consistent shape of curvature of the drum of the inside surface of canister 3, is set to the inside of canister 3.At this moment, needn't be arranged in the hand hole, so, as shown in Figure 6, can form the hole identical, thereby the size of flange 5 can be reduced with the external diameter of hermetic terminal 7.Antenna acceptance division 4 can be arranged on 2 antennas the left and right sides of hermetic terminal 7, at this moment, not only can adopt semicircular plate, and can adopt the tabular antenna of shapes such as half elliptic, rectangle.Like this, by forming antenna with curvature bending ground along the inside surface of canister 3, even be not do not put into antenna like that the hand hole of size also can install.In addition, the insulation reduction that can not reduce receiving sensitivity and prevent to cause owing to electric field is concentrated.
Example shown in Figure 7, be considered away from position situation about measuring, being provided with the transtation mission circuit 11 that match circuit and amplifier are housed will be sent by the signal that the antenna acceptance divisions in the canister 34 receive.Front end at the concentric cable 8 that is connected with transtation mission circuit 11 is provided with transmitting antenna.Determinator 10 is arranged on the position away from canister 3, and receiving antenna 12 is arranged on the determinator 10 by concentric cable 8.The partial discharge signal that is detected by antenna acceptance division 4 carries out impedance matching and amplification by transtation mission circuit 11, and sends with form of electromagnetic wave from transmitting antenna 13.By the signal that transmitting antenna 13 sends,, measure by determinator 10 by receiving antenna 12 receptions that are arranged on away from the position of air insulating device.Here, as the strong antenna of receiving antenna 12 user tropisms, utilize 1 receiving antenna 12 also can detect a plurality of partial discharge detecting devices that are installed on the air insulating device thus and partial discharge has partly taken place at which.
Example shown in Figure 8 is to make the sensitivity of antenna acceptance division 4 reach more highly sensitive example.Hemispheric reflecting plate 15 is set between antenna acceptance division 4 and flange 5, and this reflecting plate 15 forms the size identical with the internal diameter of hand hole.By adopting such structure,, can not allow the electromagnetic wave that passes through miss to 4 reflections of antenna acceptance division by reflecting plate 15 even the electromagnetic wave of propagating in air insulating device is not received by antenna acceptance division 4 and passed through yet.As a result, by assembling the electromagnetic wave that receives previously of failing effectively, just can improve sensitivity at antenna acceptance division 4.
The possibility of industrial utilization
As mentioned above, according to the partial discharge detecting device of air insulating device of the present invention, Partial discharge that can be in wide frequency band high sensitivity ground detects air insulating device. In addition, Can utilize the current potential in the static partial-pressure mensurated gas composition insulator arrangement with ground. In addition, can Prevent owing to the electric field that the air insulating device inside that antenna reception section causes is set is concentrated, Thereby can be identical with doublet antenna or be wider than in the broadband of doublet antenna also And the electromagnetic wave that in high sensitivity test section discharge takes place.

Claims (12)

1. a partial discharge detecting device that is used to have the canister of enclosing insulating gas and wherein comprises the air insulating device of the high-voltage conductor of being supported by insulation supporter comprises: the signal receiving antenna portion that is provided with in above-mentioned canister; What be connected with this signal receiving antenna portion passes through the concentric cable that coaxial hermetic terminal electrically is drawn out to above-mentioned canister outside; And the determinator that is connected with this concentric cable, it is characterized in that: signal receiving antenna has been set to a gap by 2 tabular conductive electrodes of semicircle and has relatively formed, and represents heart yearn and the outside line of the signal wire of this concentric cable to be connected with arbitrary electrode in the 2 tabular conductive electrodes of semicircle on every side of this gap of the round center that forms thus respectively.
2. by the partial discharge detecting device of the described air insulating device of claim 1, it is characterized in that: described signal receiving antenna portion is arranged on the low electric field intensity part that comprises absorbent container, particle collector or hand hole of air insulating device inside.
3. by the partial discharge detecting device of claim 1 or 2 described air insulating devices, it is characterized in that: between one of the signal wire of above-mentioned concentric cable and ground, insert capacitor.
4. by the partial discharge detecting device of claim 1 or 2 described air insulating devices, it is characterized in that: the every cube electrode in the conductive electrode that above-mentioned 2 semicircles are tabular forms the inside surface along above-mentioned canister.
5. by the partial discharge detecting device of claim 1 or 2 described air insulating devices, it is characterized in that: the marginal portion of the outer circumferential side of the every cube electrode in the conductive electrode that above-mentioned 2 semicircles are tabular forms fillet.
6. by the partial discharge detecting device of claim 1 or 2 described air insulating devices, it is characterized in that: the guarded electrode that the outer circumferential side covering of the every cube electrode in the conductive electrode that above-mentioned 2 semicircles are tabular is set.
7. by the partial discharge detecting device of claim 1 or 2 described air insulating devices, it is characterized in that: the said determination device is connected with concentric cable by coaxial connector.
8. by the partial discharge detecting device of claim 1 or 2 described air insulating devices, it is characterized in that: one of conductive electrode that above-mentioned 2 semicircles are tabular ground connection.
9. by the partial discharge detecting device of claim 1 or 2 described air insulating devices, it is characterized in that: above-mentioned signal receiving antenna portion is supported on the above-mentioned canister by insulant.
10. by the partial discharge detecting device of claim 1 or 2 described air insulating devices, it is characterized in that also comprising:
The transtation mission circuit that is connected with above-mentioned concentric cable, have impedance matching circuit and amplifier;
The signal transmitting antenna that is connected with this concentric cable;
The electromagnetic signal receiving antenna that reception sends from this signal transmitting antenna, this signal receiving antenna is connected to the said determination device.
11. by the partial discharge detecting device of the described air insulating device of claim 10, it is characterized in that: the each several part at air insulating device is provided with a plurality of above-mentioned signal transmitting antennas, and is provided with 1 above-mentioned signal receiving antenna at the said determination device.
12. partial discharge detecting device by claim 1 or 2 described air insulating devices, it is characterized in that: in above-mentioned signal receiving antenna portion and be connected between the flange of the hand hole opening that is arranged on the above-mentioned canister, also be provided with the hemispheric plate of electromagnetic wave being assembled to signal receiving antenna portion by reflection.
CN 97182201 1997-05-21 1997-05-21 Partial discharge detector of gas-insulated apparatus Expired - Lifetime CN1115566C (en)

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Application Number Priority Date Filing Date Title
CN 97182201 CN1115566C (en) 1997-05-21 1997-05-21 Partial discharge detector of gas-insulated apparatus

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Application Number Priority Date Filing Date Title
CN 97182201 CN1115566C (en) 1997-05-21 1997-05-21 Partial discharge detector of gas-insulated apparatus

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CN1115566C true CN1115566C (en) 2003-07-23

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014008718A1 (en) * 2012-07-10 2014-01-16 宁夏电力公司电力科学研究院 Signal extraction device and method for ultrahigh-frequency partial discharge sensor implanted in sulfur hexafluoride current transformer

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FR2942543B1 (en) * 2009-02-25 2011-03-25 Areva T & D Ag CAPACITIVE DEVICE AND SYSTEM FOR MEASURING THE VOLTAGE OF A HIGH-VOLTAGE ELEMENT, AND GAS-INSULATED ELECTRICAL POSITION USING THE SAME
JP5491819B2 (en) * 2009-10-02 2014-05-14 株式会社東芝 Partial discharge detector for gas-insulated electrical equipment
KR101095778B1 (en) * 2009-12-28 2011-12-21 주식회사 효성 Apparatus for partial dishcarge detection to power transformer
CN102129019A (en) * 2011-03-04 2011-07-20 上海华乘电气科技有限公司 Sensor for insulation detection of switching equipment
CN102955106B (en) * 2012-05-21 2015-08-26 厦门华电开关有限公司 Pick-up unit and insulator are put in Cubicle Gas-Insulated Switchgear office
CN102707207B (en) * 2012-06-12 2014-09-17 杭州西湖电子研究所 Simulating device for various discharges inside GIS (Gas Insulated Switchgear)
FR3024240B1 (en) * 2014-07-28 2018-02-16 Alstom Technology Ltd PARTIAL DISCHARGE DETECTION DEVICE WITH FRACTALLY ARCHITECTURED ANTENNA
CN104614645B (en) * 2015-01-16 2018-02-23 国家电网公司 GIS and its Integral grounding type superfrequency partial discharge sensor optimization method
CN113702818A (en) * 2021-08-12 2021-11-26 广东电网有限责任公司广州供电局 GIS equipment and partial discharge ultrahigh frequency monitoring assembly
CN117092455A (en) * 2022-11-01 2023-11-21 特变电工山东鲁能泰山电缆有限公司 Partial discharge detection device and partial discharge detection system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014008718A1 (en) * 2012-07-10 2014-01-16 宁夏电力公司电力科学研究院 Signal extraction device and method for ultrahigh-frequency partial discharge sensor implanted in sulfur hexafluoride current transformer

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