JPH11297145A - Insulator dirt detecting device - Google Patents
Insulator dirt detecting deviceInfo
- Publication number
- JPH11297145A JPH11297145A JP9782998A JP9782998A JPH11297145A JP H11297145 A JPH11297145 A JP H11297145A JP 9782998 A JP9782998 A JP 9782998A JP 9782998 A JP9782998 A JP 9782998A JP H11297145 A JPH11297145 A JP H11297145A
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- JP
- Japan
- Prior art keywords
- insulator
- current
- electrode
- ground
- voltage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R31/00—Arrangements for testing electric properties; Arrangements for locating electric faults; Arrangements for electrical testing characterised by what is being tested not provided for elsewhere
- G01R31/12—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing
- G01R31/1227—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials
- G01R31/1245—Testing dielectric strength or breakdown voltage ; Testing or monitoring effectiveness or level of insulation, e.g. of a cable or of an apparatus, for example using partial discharge measurements; Electrostatic testing of components, parts or materials of line insulators or spacers, e.g. ceramic overhead line cap insulators; of insulators in HV bushings
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Insulators (AREA)
- Testing Relating To Insulation (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、送変電機器又は電
力設備に用いる碍子の汚損を検知する装置に関するもの
である。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for detecting contamination of insulators used in power transmission and transformation equipment or power equipment.
【０００２】[0002]
【従来の技術】送変電機器又は電力設備に用いる碍子
は、その碍子沿面に海塩などが付着することにより絶縁
性能が低下し、最終的にフラッシュオーバのような重大
な事故に至ることがある。このような事故を防止するた
めに、碍子の汚損状態を監視し、汚損を検知したときに
碍子の洗浄などの必要な措置がとられる。2. Description of the Related Art Insulators used for power transmission and transformation equipment or power equipment have a problem in that insulation performance is deteriorated due to sea salt or the like adhering to the surface of the insulator, and eventually a serious accident such as flashover may occur. . In order to prevent such an accident, the state of contamination of the insulator is monitored, and upon detection of the contamination, necessary measures such as cleaning of the insulator are taken.
【０００３】この碍子の汚損の検知方法として従来より
種々のものが提案されている。その１例について、図１
及び図２を用いて説明する。図１は碍子汚損検知装置の
回路図を示し、図２はその等価回路を示す。碍子１は、
碍子用架台３上に搭載され、上部端子８で高圧電線２を
支持する。碍子１の接地線１５に貫通タイプの変流器１
６が設けられる。変流器１６は、接地線１５に流れる電
流を計測し、その出力は検知装置１９に入力される。な
お、碍子用架台３は碍子用絶縁架台４により接地電位部
と絶縁されているため、碍子１に流れる電流は全て接地
線１５に流れる。Various methods have been proposed for detecting the contamination of the insulator. One example is shown in FIG.
This will be described with reference to FIG. FIG. 1 shows a circuit diagram of an insulator fouling detection device, and FIG. 2 shows an equivalent circuit thereof. Insulator 1
The high voltage electric wire 2 is mounted on the insulator base 3 and supported by the upper terminal 8. Through-type current transformer 1 connected to ground wire 15 of insulator 1
6 are provided. The current transformer 16 measures the current flowing through the ground line 15, and its output is input to the detection device 19. Since the insulator base 3 is insulated from the ground potential portion by the insulator insulating base 4, all the current flowing through the insulator 1 flows through the ground line 15.
【０００４】碍子１の沿面に海塩が付着するなどして、
碍子汚損が発生すると、碍子沿面の汚損部分は抵抗体Ｒ
B となり、この抵抗体ＲB を通って電流ＩR が流れる。
この電流ＩR の値は汚損の進行に伴って増大する。ま
た、碍子１には静電容量ＣB が存在するので、接地線１
５には、静電容量ＣB による電流ＩB と汚損による電流
ＩR の合計値が流れる。[0004] When sea salt adheres to the surface of the insulator 1,
When insulator contamination occurs, the soiled portion on the surface of the insulator becomes a resistor R
B, and the current flows I R through the resistor R B.
The value of the current I R increases with the progress of the contamination. Further, since the insulator 1 there is capacitance C B, the ground line 1
5, the sum of the current I R by fouling the current I B due to the capacitance C B flows.
【０００５】検知装置１９では、変流器１６により計測
した電流から、汚損による電流ＩRを分離して、その電
流値が所定値を超えたときに、碍子１が汚損をしたと判
定する。この判定により、碍子洗浄などの必要な措置が
とられる。The detector 19 separates the current I R due to contamination from the current measured by the current transformer 16 and determines that the insulator 1 has been damaged when the current value exceeds a predetermined value. Based on this determination, necessary measures such as insulator cleaning are taken.
【０００６】[0006]
【発明が解決しようとする課題】上記従来の碍子汚損検
知装置では、変流器により碍子沿面に流れる電流を計っ
ているだけである。これに対し、碍子が汚損したときの
影響は、碍子全体の電圧分布の変化による。したがっ
て、碍子沿面に流れる電流を計測するだけでは、危険碍
子を正確に検知できない。In the above-mentioned conventional insulator fouling detecting device, only the current flowing along the insulator surface is measured by the current transformer. On the other hand, the effect of the insulator being contaminated is due to a change in the voltage distribution of the entire insulator. Therefore, a dangerous insulator cannot be accurately detected only by measuring the current flowing along the surface of the insulator.
【０００７】また、上記従来の碍子汚損検知装置では、
変流器１６の測定電流（ＩR ＋ＩB）から漏れ電流ＩR
だけを取り出す必要があり、装置の構成が複雑なものと
なる。本発明は、碍子汚損時の碍子沿面における電圧分
布を把握して、正確に碍子の汚損を検知できる汚損検知
装置を提供することを目的とするものである。[0007] Further, in the conventional insulator fouling detecting device,
From the measured current (I R + I B ) of the current transformer 16, the leakage current I R
, And the configuration of the device becomes complicated. SUMMARY OF THE INVENTION An object of the present invention is to provide a contamination detection device capable of grasping a voltage distribution on a surface of an insulator when the insulator is contaminated and accurately detecting the contamination of the insulator.
【０００８】[0008]
【課題を解決するための手段】本発明は、上記目的を達
成するために、汚損を検知しようとする碍子の接地部分
の近傍において高電圧部分に向けて配置された電極と、
電極と接地間に接続されて前記電極と前記接地間に流れ
る電流を測定する変流器とから碍子汚損検知装置を構成
する。SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides an electrode disposed near a grounded portion of an insulator for detecting a fouling and facing a high voltage portion.
A current detector connected between the electrode and the ground and measuring a current flowing between the electrode and the ground constitutes an insulator fouling detecting device.
【０００９】上記構成により電極と高電圧部の間に静電
容量Ｃ0 が生じ、この静電容量Ｃ0により発生する電流
Ｉ0 は、変流器を通して接地に流れる。したがって、変
流器は、碍子の無汚損時には、電極と高電圧部の間に発
生する静電容量Ｃ0 による電流Ｉ0 を計測する。碍子が
汚損をすると、碍子の沿面における汚損部分は一種の抵
抗体となり、碍子沿面に電圧降下を発生させる。この電
圧降下後の電圧ＶS と電極間に静電容量ＣS が発生し、
この静電容量ＣS により電極と接地間に電流ＩS が流れ
る。この結果、碍子汚損時には、電極と接地間には、電
極と高電圧部との間の静電容量Ｃ 0 による電流Ｉ0 と、
碍子汚損時に発生する静電容量ＣS による電流ＩS の合
計値が流れる。With the above configuration, an electrostatic charge is applied between the electrode and the high voltage portion.
Capacity C0And the capacitance C0Current generated by
I0Flows to ground through a current transformer. Therefore,
When the insulator is not contaminated, a current flow occurs between the electrode and the high-voltage section.
Generated capacitance C0Current I0Is measured. Insulator
When soiling occurs, the soiled area on the surface of the insulator is a kind of resistance.
It becomes an antibody, causing a voltage drop across the insulator. This
Voltage V after pressure dropSAnd the capacitance C between the electrodesSOccurs,
This capacitance CSThe current I between the electrode and groundSFlows
You. As a result, when the insulator is contaminated, there is no electrical connection between the electrode and ground.
Capacitance C between pole and high voltage part 0Current I0When,
Capacitance C generated when insulator is soiledSCurrent ISIf
The measured value flows.
【００１０】この碍子汚損時に発生する電流ＩS は、碍
子無汚損時に流れる電流Ｉ0 と比較すると、はるかに大
きい値を示す。したがって、変流器が計測した碍子無汚
損時の電流Ｉ0 と碍子汚損時の電流Ｉ0 ＋ＩS を比較す
ることにより、碍子の汚損を簡単に検知することができ
る。また、この電流の変化は、碍子沿面の電圧分布の変
化に応じたもので、碍子汚損による影響を正確に反映し
たものである。本発明においては、碍子の汚損時、無汚
損時のいずれにおいても、碍子の静電容量ＣB により流
れる電流ＩB は直接接地へ流れるので、変流器はこの電
流ＩB を計測せず、この電流の影響を受けない。The current I S generated when the insulator is contaminated has a much larger value than the current I 0 flowing when the insulator is not contaminated. Therefore, by current transformer for comparing the current I 0 + I S during current I 0 and insulator fouling during insulators no fouling measured, it is possible to easily detect the fouling of the insulator. The change in the current is in accordance with the change in the voltage distribution on the surface of the insulator, and accurately reflects the effect of insulator contamination. In the present invention, when the insulator of fouling in either the time of no fouling, since the current I B that flows through the capacitance C B of the insulator flows directly to ground, the current transformer does not measure this current I B, It is not affected by this current.
【００１１】[0011]
【発明の実施の形態】本発明の実施形態について図３〜
図６を用いて説明する。図３は碍子無汚損時の碍子汚損
検知装置の回路構成を示し、図４はその等価回路を示
す。図５は碍子の汚損時の碍子汚損検知装置の回路構成
を示す。図６はその等価回路を示す。碍子１は、碍子用
架台３上に搭載され、上部端子８が高圧電線２を支持す
る。碍子下端は接地線５を介して接地される。碍子用架
台３は、碍子用絶縁架台４に搭載される。碍子１は、図
１の従来例と同様に、浮遊静電容量ＣB を有している。DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention are shown in FIGS.
This will be described with reference to FIG. FIG. 3 shows a circuit configuration of the insulator fouling detection device when the insulator is not stained, and FIG. 4 shows an equivalent circuit thereof. FIG. 5 shows a circuit configuration of the insulator fouling detecting device when the fouling of the insulator occurs. FIG. 6 shows an equivalent circuit thereof. The insulator 1 is mounted on the insulator base 3, and the upper terminal 8 supports the high-voltage wire 2. The lower end of the insulator is grounded via a ground line 5. The insulator gantry 3 is mounted on the insulator gantry 4. Insulator 1, as in the conventional example of FIG. 1 has a stray capacitance C B.
【００１２】碍子１の下端に近接して電極７が設けられ
る。この電極７は高圧電線２に対向して配置され、高圧
電線２との間に浮遊静電容量Ｃ0 が発生する。また、電
極７と碍子用架台３との間に変流器６の１次側が接続さ
れる。変流器６の２次側は検知装置９に接続される。な
お、この変流器６は、接地線５に流れる電流が小さいた
め、図１に示した従来の貫通タイプの変流器６ではな
く、複巻タイプの変流器が使用される。An electrode 7 is provided near the lower end of the insulator 1. The electrode 7 is arranged so as to face the high-voltage wire 2, and a floating capacitance C 0 is generated between the electrode 7 and the high-voltage wire 2. The primary side of the current transformer 6 is connected between the electrode 7 and the insulator base 3. The secondary side of the current transformer 6 is connected to the detecting device 9. Since the current flowing through the ground wire 5 is small, the current transformer 6 is not a conventional through-type current transformer 6 shown in FIG. 1 but a compound current transformer.
【００１３】高圧電線２と電極７の間に発生する静電容
量Ｃ0 により流れる電流Ｉ0 は、変流器６を通して接地
に流れる。変流器６は、碍子１に流れる電流ＩB は計測
せず、高圧電線２と接地間の静電容量Ｃ0 に流れる電流
ＩB のみを計測する。碍子１が汚損すると、図５に示す
ように、碍子１の沿面に海塩が付着するなどして汚損し
た範囲１０が発生する。この範囲１０は、抵抗体ＲS と
みなされる。この碍子１の汚損により新たに発生した抵
抗体ＲS と電極７との間に浮遊静電容量ＣS が発生す
る。このときの等価回路が図６に示される。抵抗体ＲS
による電圧降下後の電圧ＶS と静電容量ＣS により、電
極７と接地間に電流ＩS が流れる。この結果、変流器６
は、２つの静電容量Ｃ0 及びＣS による電流の合計値Ｉ
S0（＝ＩS ＋Ｉ0 ）を計測する。The current I 0 flowing between the high voltage electric wire 2 and the electrode 7 due to the capacitance C 0 flows through the current transformer 6 to the ground. Current transformer 6, the current I B that flows through the insulator 1 without measurement, measuring only current I B flowing through the electrostatic capacitance C 0 between the ground and the high-voltage wire 2. When the insulator 1 is soiled, as shown in FIG. 5, a soiled area 10 is generated due to sea salt adhering to the surface of the insulator 1. This range 10 is regarded as the resistor R S. The floating capacitance C S is generated between the resistor R S and the electrode 7 newly generated due to the contamination of the insulator 1. FIG. 6 shows an equivalent circuit at this time. Resistor R S
Due to the voltage V S and the capacitance C S after the voltage drop due to the above, a current I S flows between the electrode 7 and the ground. As a result, the current transformer 6
Is the sum of the currents I due to the two capacitances C 0 and C S,
S0 (= I S + I 0 ) to measure.
【００１４】碍子１の汚損が進行すると、汚損により発
生した静電容量ＣS による電流ＩSが増加する。一方、
静電容量Ｃ0 及び電流Ｉ0 は、汚損の程度に関係なく一
定である。したがって、変流器６に流れる電流ＩS0（＝
ＩS ＋Ｉ0 ）は、碍子１の汚損の進行に伴って増加す
る。この電流ＩS0は、高圧電線２の印加電圧などにより
異なるが、例えば、碍子無汚損時に静電容量Ｃ0 による
電流Ｉ0 が数μＡであるとすると、汚損時のＩSO（＝Ｉ
S ＋Ｉ0 ）は数百μＡから数ｍＡに達する。When the pollution of the insulator 1 proceeds, the current I S due to the capacitance C S generated by the pollution increases. on the other hand,
The capacitance C 0 and the current I 0 are constant regardless of the degree of contamination. Therefore, the current I S0 (=
I S + I 0 ) increases as the contamination of the insulator 1 progresses. The current I S0 varies due the applied voltage of the high-voltage electric wire 2, for example, when the current I 0 by the electrostatic capacitance C 0 when the insulator no fouling and the number .mu.A, when fouling I SO (= I
(S + I 0 ) ranges from several hundred μA to several mA.
【００１５】このように、碍子無汚損時と汚損時とでは
電流値が大幅に異なるため、汚損の検知が容易に行え
る。検知装置９は、変流器６が計測した電流ＩS0の値が
所定のしきい値を超えたときに、碍子１に汚損が発生し
たと判断して、外部に所定の信号を出力する。この信号
が出力されると、碍子１の洗浄などの必要な措置がとら
れる。As described above, since the current value is significantly different between when the insulator is not stained and when the insulator is stained, it is possible to easily detect the stain. When the value of the current I S0 measured by the current transformer 6 exceeds a predetermined threshold value, the detection device 9 determines that the insulator 1 has been contaminated, and outputs a predetermined signal to the outside. When this signal is output, necessary measures such as cleaning of the insulator 1 are taken.
【００１６】以上説明した検知装置においては、変流器
６に流れる電流ＩS0を計測することにより、碍子１の沿
面汚損による電圧分布の変化を検知している。このた
め、碍子の汚損による碍子沿面の電圧分布を正確に把握
して、汚損による影響を容易に検知することができる。
電極７について更に詳細に説明をする。In the detection device described above, the change of the voltage distribution due to the surface contamination of the insulator 1 is detected by measuring the current I S0 flowing through the current transformer 6. Therefore, it is possible to accurately grasp the voltage distribution on the surface of the insulator due to the contamination of the insulator, and easily detect the influence of the contamination.
The electrode 7 will be described in more detail.
【００１７】電極７は、高圧電線２及び碍子１の沿面に
対向して、それらの間に浮遊静電容量Ｃ0 、ＣS が発生
するように配置される。また、碍子１の下端近傍に配置
するときは、電極７に地絡をしないように、碍子の下端
から十分な距離だけ離して配置される。さらに、電極７
は、高電圧部の電界の影響を受けない形状とされる。図
７、図８は、電極７の構造例を示す。The electrode 7 is disposed so as to face the high-voltage electric wire 2 and the insulator 1 so as to generate stray capacitances C 0 and C S therebetween. Further, when it is arranged near the lower end of the insulator 1, it is arranged at a sufficient distance from the lower end of the insulator so as not to ground the electrode 7. Further, the electrode 7
Have a shape that is not affected by the electric field of the high voltage portion. 7 and 8 show a structural example of the electrode 7.
【００１８】図７において、左側は正面図、右側は断面
図を示す。図７（Ａ）は、電極を平板により構成した例
を示す。平板の各角部にはＲを持たせて、電界から影響
を受けないようにしている。図７（Ｂ）は、電極をリン
グにより構成した例を示す。リングの断面は円形とされ
て、電界から影響を受けないようにしている。In FIG. 7, the left side is a front view, and the right side is a sectional view. FIG. 7A shows an example in which the electrode is formed of a flat plate. Each corner of the flat plate is provided with an R so as not to be affected by the electric field. FIG. 7B shows an example in which the electrodes are formed by rings. The cross-section of the ring is circular so that it is not affected by the electric field.
【００１９】図７（Ｃ）は、電極をリングにより構成し
た例を示す。リングの断面は楕円形とされて、電界から
影響を受けないようにしている。図８は、電極をリング
状に構成し、このリングを碍子１の下端を囲うように配
置した例を示す。FIG. 7C shows an example in which the electrodes are formed by rings. The cross section of the ring is elliptical, so that it is not affected by the electric field. FIG. 8 shows an example in which the electrodes are formed in a ring shape and this ring is arranged so as to surround the lower end of the insulator 1.
【図１】従来の碍子汚損検知装置の回路構成図。FIG. 1 is a circuit configuration diagram of a conventional insulator contamination detection device.
【図２】図１の等価回路図。FIG. 2 is an equivalent circuit diagram of FIG.
【図３】本発明を適用した碍子汚損検知装置の回路構成
図（碍子無汚損時）。FIG. 3 is a circuit diagram of an insulator fouling detection device to which the present invention is applied (when the insulator is not fouled).
【図４】図３の等価回路図。FIG. 4 is an equivalent circuit diagram of FIG. 3;
【図５】本発明を適用した碍子汚損検知装置の回路構成
図（碍子汚損時）。FIG. 5 is a circuit diagram of an insulator fouling detection device to which the present invention is applied (when the insulator is fouled).
【図６】図５の等価回路図。FIG. 6 is an equivalent circuit diagram of FIG. 5;
【図７】本発明に使用する電極の構成を示す図。FIG. 7 is a diagram showing a configuration of an electrode used in the present invention.
【図８】本発明に使用する電極の変形例を示す図。FIG. 8 is a diagram showing a modification of the electrode used in the present invention.
１…碍子 ２…高圧電線 ３…碍子用架台 ４…碍子用絶縁架台 ５…接地線 ６…変流器 ７…電極 ８…上部端子 ９…検知装置 １０…汚損範囲 DESCRIPTION OF SYMBOLS 1 ... Insulator 2 ... High voltage electric wire 3 ... Insulator stand 4 ... Insulator stand 5 ... Grounding wire 6 ... Current transformer 7 ... Electrode 8 ... Upper terminal 9 ... Detector 10 ... Soil range
Claims (1)
おいて高電圧部分に向けて配置された電極と、 この電極と接地間に接続されて前記電極と前記接地間に
流れる電流を測定する変流器とを具備することを特徴と
する碍子汚損検知装置。An electrode disposed near a grounded portion of an insulator for detecting fouling and directed toward a high-voltage portion, a transformer connected between the electrode and a ground and measuring a current flowing between the electrode and the ground. An insulator fouling detection device comprising a flow device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9782998A JPH11297145A (en) | 1998-04-09 | 1998-04-09 | Insulator dirt detecting device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9782998A JPH11297145A (en) | 1998-04-09 | 1998-04-09 | Insulator dirt detecting device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH11297145A true JPH11297145A (en) | 1999-10-29 |
Family
ID=14202622
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9782998A Pending JPH11297145A (en) | 1998-04-09 | 1998-04-09 | Insulator dirt detecting device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH11297145A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1175623A1 (en) * | 1999-04-02 | 2002-01-30 | Lindsey Manufacturing Company | Insulator support current sensor |
| CN1320366C (en) * | 2001-11-05 | 2007-06-06 | 北京深浪电子技术有限公司 | Detection method and device for live insulator in high-voltage transmission line |
-
1998
- 1998-04-09 JP JP9782998A patent/JPH11297145A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1175623A1 (en) * | 1999-04-02 | 2002-01-30 | Lindsey Manufacturing Company | Insulator support current sensor |
| EP1175623A4 (en) * | 1999-04-02 | 2003-01-15 | Lindsey Mfg Company | Insulator support current sensor |
| US6555999B1 (en) | 1999-04-02 | 2003-04-29 | Lindsey Manufacturing Company | Insulator support current sensor |
| CN1320366C (en) * | 2001-11-05 | 2007-06-06 | 北京深浪电子技术有限公司 | Detection method and device for live insulator in high-voltage transmission line |
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