JPH0535390B2 - - Google Patents
Info
- Publication number
- JPH0535390B2 JPH0535390B2 JP59171727A JP17172784A JPH0535390B2 JP H0535390 B2 JPH0535390 B2 JP H0535390B2 JP 59171727 A JP59171727 A JP 59171727A JP 17172784 A JP17172784 A JP 17172784A JP H0535390 B2 JPH0535390 B2 JP H0535390B2
- Authority
- JP
- Japan
- Prior art keywords
- optical fiber
- deterioration
- insulation
- insulating layer
- time
- 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.)
- Expired - Lifetime
Links
- 230000006866 deterioration Effects 0.000 claims description 32
- 239000013307 optical fiber Substances 0.000 claims description 31
- 238000009413 insulation Methods 0.000 claims description 24
- 238000002834 transmittance Methods 0.000 claims description 14
- 238000006243 chemical reaction Methods 0.000 claims description 12
- 238000012806 monitoring device Methods 0.000 claims description 7
- 239000012212 insulator Substances 0.000 claims description 4
- 239000000126 substance Substances 0.000 description 8
- 239000004020 conductor Substances 0.000 description 7
- 238000012360 testing method Methods 0.000 description 7
- 230000007423 decrease Effects 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 238000010998 test method Methods 0.000 description 5
- 230000015556 catabolic process Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000012423 maintenance Methods 0.000 description 3
- 229920002574 CR-39 Polymers 0.000 description 2
- 230000002411 adverse Effects 0.000 description 2
- 238000003745 diagnosis Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000008439 repair process Effects 0.000 description 2
- NNWNNQTUZYVQRK-UHFFFAOYSA-N 5-bromo-1h-pyrrolo[2,3-c]pyridine-2-carboxylic acid Chemical compound BrC1=NC=C2NC(C(=O)O)=CC2=C1 NNWNNQTUZYVQRK-UHFFFAOYSA-N 0.000 description 1
- 230000002159 abnormal effect Effects 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000005253 cladding Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 239000011162 core material Substances 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 239000002243 precursor Substances 0.000 description 1
- 230000003449 preventive effect Effects 0.000 description 1
- 229920005573 silicon-containing polymer Polymers 0.000 description 1
Landscapes
- Testing Relating To Insulation (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、電気機器絶縁の熱劣化度を、実働機
器の運動を停止することなく連続監視する装置に
関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device that continuously monitors the degree of thermal deterioration of electrical equipment insulation without stopping the operation of the equipment.
周知のように、電気機器の絶縁は熱、放電、そ
の他の因子により劣化し、究極的には絶縁破壊に
至るが、機器の信頼、ひいては電気機器を装備し
た設備の信頼性を維持するため、予防保全の一環
として定期的に運動を停止して絶縁診断を行なう
ことが多い。
As is well known, the insulation of electrical equipment deteriorates due to heat, discharge, and other factors, ultimately leading to insulation breakdown, but in order to maintain the reliability of the equipment and, by extension, the reliability of the equipment equipped with the electrical equipment, As part of preventive maintenance, it is common to periodically stop the vehicle and perform insulation diagnosis.
しかし、現状の電気的試験による絶縁診断法
（直流試験法、交流電流試験法、誘電正接試験法、
部分放電試験法、接地線漏れ電流試験法）では、
試験電圧が被測定電気機器の定格電圧までしか印
加できないため、得られる諸特性の変化は小さ
く、加えて、その試験結果は試験時の環境条件、
特に湿度の影響を受けるため、絶縁劣化との安定
した対応がとれないまま、経験的に劣化状況を推
測していることや、機器の運動を停止させての測
定で、劣化の連続監視ができない等の問題があ
る。 However, the current insulation diagnosis methods using electrical tests (DC test method, AC current test method, dielectric loss tangent test method,
partial discharge test method, ground wire leakage current test method),
Since the test voltage can only be applied up to the rated voltage of the electrical equipment under test, changes in the obtained characteristics are small.In addition, the test results are dependent on the environmental conditions at the time of the test,
In particular, since it is affected by humidity, the deterioration status is estimated empirically without being able to take stable measures against insulation deterioration, and continuous monitoring of deterioration is not possible because measurements are made with equipment stopped moving. There are other problems.
これらの問題を解決するために、高圧機器の絶
縁層の表面に電極を設置し、絶縁破壊の前駆現象
としての部分放電パルスを、機器の運転を停止す
ることなく連続的に検出する方法や、絶縁層に超
音波発振子を埋設し、超音波深傷により絶縁劣化
を連続的に検出する方法などが提唱されている。 In order to solve these problems, we have developed a method of installing electrodes on the surface of the insulating layer of high-voltage equipment to continuously detect partial discharge pulses, which are precursors to dielectric breakdown, without stopping equipment operation. A method has been proposed in which an ultrasonic oscillator is embedded in an insulating layer and insulation deterioration is continuously detected by ultrasonic deep damage.
しかしそれらは導電性の材料を絶縁層の表面に
設置するか、導電性の材料を絶縁層の内部に埋設
し、リードを取り出すため、絶縁に悪影響を及ぼ
す場合がある。また絶縁劣化との対応もいまだ十
分ではない。 However, in these methods, a conductive material is placed on the surface of the insulating layer, or a conductive material is buried inside the insulating layer, and the leads are taken out, which may have an adverse effect on the insulation. Furthermore, measures against insulation deterioration are still insufficient.
更に、接地線に流れる漏洩電流を連続的に検出
する方法も提唱されているが、機器の運転電圧下
での情報であり、その変化は小さい。 Furthermore, a method has been proposed in which the leakage current flowing through the grounding wire is continuously detected, but the information is obtained under the operating voltage of the equipment, and its changes are small.
本発明は、従来の方法の、試験中において機器
の運転を停止しなければならないという問題点、
あるいは実際の絶縁劣化との対応性がとれないと
いう問題点を解決しようとするものであり、電気
機器などの保全における修理や更新などの処置を
データベースに信頼度高く行なうことができる絶
縁監視装置を提供することを目的とするものであ
る。
The present invention solves the problem of the conventional method that the operation of the equipment must be stopped during the test,
Another attempt is to solve the problem of not being able to respond to actual insulation deterioration, and to develop an insulation monitoring device that can use a database to perform highly reliable repairs and updates during the maintenance of electrical equipment. The purpose is to provide
本発明の絶縁監視装置は、絶縁層内に埋設した
光フアイバーと、この光フアイバーの一端に設け
た発光部と、前記光フアイバーの他端に設けた受
光部と、化学反応速度式に基づいて得られる光フ
アイバーの透光率の変化と熱劣化の換算時間との
関係を予め記憶し、前記受光部の出力に対応する
換算時間を出力する関数発生部と、この関数発生
部の出力が前記絶縁層を構成する絶縁物の寿命点
での換算時間に相当するものとなつたときに表示
又は警報を行なう表示部とからなるものであり、
光フアイバーの熱劣化による透光率の変化を絶縁
物の劣化の関数としてとらえるようにしたもので
ある。以下具体的に説明する。
The insulation monitoring device of the present invention includes an optical fiber embedded in an insulating layer, a light emitting part provided at one end of the optical fiber, a light receiving part provided at the other end of the optical fiber, and a chemical reaction rate equation. a function generating section that stores in advance the relationship between the change in the light transmittance of the obtained optical fiber and the converted time of thermal deterioration, and outputs the converted time corresponding to the output of the light receiving section; It consists of a display section that displays or gives an alarm when the time corresponds to the lifespan of the insulating material constituting the insulating layer,
The change in light transmittance due to thermal deterioration of the optical fiber is considered as a function of the deterioration of the insulator. This will be explained in detail below.
電気機器の絶縁劣化は、主として熱劣化により
もたらされる。 Insulation deterioration of electrical equipment is mainly caused by thermal deterioration.
一般に、熱劣化による電気機器絶縁物の化学構
造量の変化は、化学反応速度論に従うと言われて
いる。また、本発明において絶縁層内に埋設した
光フアイバーの、熱劣化による化学構造量の変化
も、化学反応速度論に従い、かつ透光率は化学構
造量で一義的に決まると言われている。 It is generally said that changes in the chemical structure of electrical equipment insulators due to thermal deterioration follow chemical reaction kinetics. Further, in the present invention, it is said that the change in the amount of chemical structure due to thermal deterioration of the optical fiber embedded in the insulating layer also follows chemical reaction kinetics, and the light transmittance is uniquely determined by the amount of chemical structure.
即ち、熱劣化による有機光フアイバーと化学構
造量Ｘの変化が化学反応速度論に従うとすれば、
化学構造量Ｘの変化は、
dx／dt＝Ａ・exp（−ΔE／RT）・ｇ(x)……(1)式
で表わされる。ここで、ｔは劣化時間、Ａは頻度
因子、ΔEは活性化エネルギー、Ｒはガス定数、
Ｔは劣化の絶対温度、ｇ(x)は反応機構を表す関数
である。 In other words, if the changes in the organic optical fiber and the chemical structure amount X due to thermal deterioration follow chemical reaction kinetics, then
The change in the chemical structure amount X is expressed by the following formula: dx/dt=A・exp(−ΔE/RT)・g(x) (1). Here, t is the degradation time, A is the frequency factor, ΔE is the activation energy, R is the gas constant,
T is the absolute temperature of deterioration, and g(x) is a function representing the reaction mechanism.
有機光フアイバーの劣化が時間０からｔまで進
み、化学構造量がxpからｘまで変化したとして(1)
式を積分すると
∫x xpdx／ｇ(x)＝A∫t p（−ΔE／RT）dt ……(2)式
となり、右辺の積分は時間の次元となるので、換
算時間θと呼ばれている。 Assuming that the organic optical fiber deteriorates from time 0 to t and the chemical structure changes from x p to x (1)
Integrating the equation yields ∫ x xp dx/g(x)=A∫ t p (−ΔE/RT) dt...(2), and the integral on the right side is the dimension of time, so it is called the reduced time θ. ing.
θ＝∫t pexp（−ΔE／RT）・dt ……(3)式 従つて(2)式は、 ∫x xdx／ｇ(x)＝Ａ・θ ……(4)式 で表わされる。 θ=∫ t p exp (−ΔE/RT)・dt ...Equation (3) Therefore, Equation (2) is expressed as ∫ x x dx/g(x)=A・θ ...Equation (4) .
反応機構を表す関数ｇ(x)と頻度因子Ａが一定の
劣化領域では、種々の温度条件下で劣化が生じて
も、換算時間θが等しければ化学構造量ｘの変化
も等しくなり、
θ−ｆ(x) ……(5)式
と表される。 In a deterioration region where the function g(x) expressing the reaction mechanism and the frequency factor A are constant, even if deterioration occurs under various temperature conditions, if the converted time θ is the same, the change in the chemical structure amount x will be the same, and θ- f(x) ... is expressed as equation (5).
更に、透光率Ｐが化学構造量で一義的に決まる
とすると、
Ｐ＝ｈ(x) ……(6)式
となる。従つて、劣化の換算時間θと透光率Ｐ
は、
θ＝ｆ｛h-1(P)｝ ……(7)式
と表され、有機光フアイバーの透光率Ｐの変化か
ら、熱劣化度の尺度となる劣化の換算時間θを求
めることができる。 Furthermore, assuming that the light transmittance P is uniquely determined by the amount of chemical structure, P=h(x)...Equation (6) is obtained. Therefore, the conversion time θ of deterioration and the light transmittance P
is expressed as θ=f{h -1 (P)}...Equation (7), and the conversion time θ of deterioration, which is a measure of the degree of thermal deterioration, is calculated from the change in the light transmittance P of the organic optical fiber. I can do it.
以下に、回転機絶縁線輪の導体間隙に埋設した
有機光フアイバー、例えばコア剤にアリルジグリ
コールカーボネートポリマー（PRG
INDUSTRIES、Inc.CR−39（登録商標））を、ク
ラツド材にシリコーンポリマーを用いた有機光フ
アイバーより、本発明を具体的に説明する。
The following describes an organic optical fiber embedded in the conductor gap of a rotating machine insulated wire ring, for example, allyl diglycol carbonate polymer (PRG) is used as the core material.
INDUSTRIES, Inc. CR-39 (registered trademark)) is an organic optical fiber using a silicone polymer as a cladding material.
第１図は本発明実施例の概略図、第２図はその
−線断面図である。この実施例では、導体１
と主絶縁４との間隙２に、有機光フアイバー３を
埋設し、補助絶縁５を施した後に、含浸剤を含浸
した線輪から出てくる光フアイバー３の一方を発
光素子６に、他方を受光素子７にそれぞれ接続
し、更に受光素子７の出力を増幅器８で増幅した
後、予め求めた受光量と有機光フアイバーの劣化
度θとの関係を記憶した関数発生部９に信号を入
力し、その関数発生部９の出力を表示・警報回路
１０に接続したものである。 FIG. 1 is a schematic diagram of an embodiment of the present invention, and FIG. 2 is a cross-sectional view taken along the line -2. In this example, conductor 1
An organic optical fiber 3 is buried in the gap 2 between the main insulation 4 and the auxiliary insulation 5, and one of the optical fibers 3 coming out of the coil impregnated with an impregnating agent is connected to the light emitting element 6, and the other is connected to the light emitting element 6. After connecting to the light-receiving elements 7 and amplifying the output of the light-receiving elements 7 with an amplifier 8, a signal is inputted to a function generator 9 that stores the relationship between the amount of received light and the degree of deterioration θ of the organic optical fiber determined in advance. , the output of the function generator 9 is connected to a display/alarm circuit 10.
上記構成の監視装置において、機器の運転によ
り線輪の温度が上昇すると、有機光フアイバーは
劣化を受けて透光率Ｐが小さくなるため、受光素
子６の出力が低下してくる。劣化の尺度となる換
算時間θと透光率Ｐは、前記の(7)式に示したよう
に一義的関係にあり、劣化が進むにつれて、つま
りθが大きくなるほど透光率Ｐは小さくなり、受
光素子の出力は低下してくる。 In the monitoring device having the above configuration, when the temperature of the coil increases due to operation of the device, the organic optical fiber is deteriorated and the light transmittance P becomes small, so that the output of the light receiving element 6 decreases. The converted time θ, which is a measure of deterioration, and the light transmittance P have a unique relationship as shown in equation (7) above, and as the deterioration progresses, that is, as θ increases, the light transmittance P decreases. The output of the light receiving element decreases.
一般的な有機光フアイバーでは、劣化の換算時
間θと受光素子の出力との関係は、第３図に示す
曲線１１のようになる。いま、IEEE117などの試
験法で求めた絶縁線輪の寿命点での換算時間がθe
であるとすると、このθeを第３図の横軸上に1.0
と目盛つて寿命点としておくと、受光素子の出力
から絶縁線輪の余寿命を透光率と時間の関数とし
て推定することができる。また、任意の劣化度の
レベルで警報を発することもできる。 In a general organic optical fiber, the relationship between the converted deterioration time θ and the output of the light receiving element is as shown by a curve 11 shown in FIG. Now, the conversion time θe at the life point of the insulated coil obtained by testing methods such as IEEE117 is
, this θe is plotted as 1.0 on the horizontal axis in Figure 3.
By setting the scale as the life point, the remaining life of the insulated coil can be estimated from the output of the light receiving element as a function of light transmittance and time. It is also possible to issue a warning at any level of deterioration.
この実施例では、有機光フアイバーを埋設した
任意の場所の、局部的な異常劣化が検出できると
ともに、絶縁線輪の全ての導体間隙に有機光フア
イバーを埋設すれば、線輪全体の劣化を検出する
ことができる。 In this example, local abnormal deterioration can be detected at any location where organic optical fibers are buried, and if organic optical fibers are buried in all conductor gaps of the insulated wire ring, deterioration of the entire wire ring can be detected. can do.
なお、有機光フアイバーは絶縁物であり、光フ
アイバー埋設による絶縁への悪影響はないことは
言うまでもない。 Note that the organic optical fiber is an insulator, and it goes without saying that burying the optical fiber does not have any adverse effect on the insulation.
上記実施例で述べた有機道フアイバーの透光率
の低下以外にも、他の有機光フアイバーの透光率
の低下現象も利用できることは勿論、監視する絶
縁システムの耐熱クラスによつては、石英系の光
フアイバーによる検出も可能である。 In addition to the decrease in the light transmittance of organic optical fibers described in the above embodiments, it is possible to utilize the phenomenon of decrease in transmittance of other organic optical fibers, and depending on the heat resistance class of the insulation system to be monitored, Detection using optical fibers in the system is also possible.
また、本発明の監視装置は、電気機器絶縁に限
ることなく、他の分野でも使用できることは言う
までもない。 Furthermore, it goes without saying that the monitoring device of the present invention can be used not only in electrical equipment insulation but also in other fields.
上述したように本発明の絶縁監視装置によれ
ば、絶縁層内に埋設した光フアイバーの透光率の
変化から、絶縁層の劣化の直接的な情報である劣
化の換算時間が得られるとともに、劣化度を機器
の運転中も含めて電気信号として連続的に取り出
せ、保全における修理や更新などの処置を、デー
タベースに信頼度高く、かつタイムリーに行なう
ことができるという効果を奏するものである。
As described above, according to the insulation monitoring device of the present invention, the deterioration conversion time, which is direct information on the deterioration of the insulating layer, can be obtained from the change in the light transmittance of the optical fiber embedded in the insulating layer, and The degree of deterioration can be continuously retrieved as an electrical signal even while the equipment is in operation, and maintenance repairs and updates can be carried out in a highly reliable database and in a timely manner.
第１図は本発明の実施例の構成を示す概略図、
第２図は第１図の−線における断面図、第３
図は換算時間と受光素子の出力との関係を示すグ
ラフである。
１：導体、２：導体・主絶縁間間隙、３：有機
光フアイバー、４：主絶縁、５：補助絶縁、６：
発光素子、７：受光素子、８：増幅器、９：関数
発生部、１０：表示・警報回路。
FIG. 1 is a schematic diagram showing the configuration of an embodiment of the present invention,
Figure 2 is a sectional view taken along the - line in Figure 1;
The figure is a graph showing the relationship between the converted time and the output of the light receiving element. 1: Conductor, 2: Gap between conductor and main insulation, 3: Organic optical fiber, 4: Main insulation, 5: Auxiliary insulation, 6:
Light emitting element, 7: Light receiving element, 8: Amplifier, 9: Function generator, 10: Display/alarm circuit.
Claims (1)
と、この光フアイバーの一端に設けた発光部と、
前記光フアイバーの他端に設けた受光部と、化学
反応速度式に基づいて得られる光フアイバーの透
光率の変化と熱劣化の換算時間との関係を予め記
憶し、前記受光部の出力に対応する換算時間を出
力する関数発生部と、この関数発生部の出力が前
記絶縁層を構成する絶縁物の寿命点での換算時間
に相当するものとなつたときに表示又は警報を行
なう表示部とからなる絶縁監視装置。 ２ 光フアイバーは有機光フアイバーである特許
請求の範囲第１項記載の絶縁監視装置。[Scope of Claims] 1. An optical fiber whose middle part is buried in an insulating layer, a light emitting part provided at one end of this optical fiber,
A light receiving section provided at the other end of the optical fiber is stored in advance, and the relationship between the change in light transmittance of the optical fiber obtained based on the chemical reaction rate equation and the conversion time of thermal deterioration is stored, and the output of the light receiving section is A function generating section that outputs a corresponding converted time, and a display section that displays or issues an alarm when the output of this function generating section corresponds to the converted time at the life point of the insulator constituting the insulating layer. An insulation monitoring device consisting of. 2. The insulation monitoring device according to claim 1, wherein the optical fiber is an organic optical fiber.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17172784A JPS6148772A (en) | 1984-08-17 | 1984-08-17 | Insulation monitoring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17172784A JPS6148772A (en) | 1984-08-17 | 1984-08-17 | Insulation monitoring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6148772A JPS6148772A (en) | 1986-03-10 |
| JPH0535390B2 true JPH0535390B2 (en) | 1993-05-26 |
Family
ID=15928554
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP17172784A Granted JPS6148772A (en) | 1984-08-17 | 1984-08-17 | Insulation monitoring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6148772A (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS498296A (en) * | 1972-05-11 | 1974-01-24 | ||
| JPS51143369A (en) * | 1975-06-04 | 1976-12-09 | Hitachi Ltd | Detection method of dielectric deterioration of electric appliances |
| JPS572431B2 (en) * | 1978-04-07 | 1982-01-16 |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6038202Y2 (en) * | 1980-06-05 | 1985-11-14 | 日立電線株式会社 | Temperature sensor using optical fiber |
-
1984
- 1984-08-17 JP JP17172784A patent/JPS6148772A/en active Granted
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS498296A (en) * | 1972-05-11 | 1974-01-24 | ||
| JPS51143369A (en) * | 1975-06-04 | 1976-12-09 | Hitachi Ltd | Detection method of dielectric deterioration of electric appliances |
| JPS572431B2 (en) * | 1978-04-07 | 1982-01-16 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6148772A (en) | 1986-03-10 |
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