JPS5829873B2 - Method for determining insulation deterioration of rotating machine stator windings - Google Patents
Method for determining insulation deterioration of rotating machine stator windingsInfo
- Publication number
- JPS5829873B2 JPS5829873B2 JP51032751A JP3275176A JPS5829873B2 JP S5829873 B2 JPS5829873 B2 JP S5829873B2 JP 51032751 A JP51032751 A JP 51032751A JP 3275176 A JP3275176 A JP 3275176A JP S5829873 B2 JPS5829873 B2 JP S5829873B2
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- Japan
- Prior art keywords
- discharge
- voltage
- test
- maximum
- charge
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- 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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- Testing Relating To Insulation (AREA)
- Tests Of Circuit Breakers, Generators, And Electric Motors (AREA)
- Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)
Description
【発明の詳細な説明】
本発明は回転機固定子巻線の絶縁劣化判定方法に関する
ものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for determining insulation deterioration of a stator winding of a rotating machine.
電力系統に接続される発電機、調和機その他の回転機の
固定子巻線を、系統に発生する異常電圧から保護するた
めには、異常電圧を考慮した電圧値(我国では(2E+
1)KV(E:定格電圧)に定められている。In order to protect the stator windings of generators, harmonizers, and other rotating machines connected to the power grid from abnormal voltages that occur in the grid, voltage values that take abnormal voltages into account (in Japan (2E+
1) Defined in KV (E: rated voltage).
)に耐える絶縁状態を維持させることが必要であり、こ
のためには定期的な点検により所望の絶縁状態に保たれ
ているかを絶えず監視する必要がある。), it is necessary to maintain an insulation state that can withstand high temperatures, and for this purpose, it is necessary to constantly monitor whether the desired insulation state is maintained through periodic inspections.
この場合前記の電圧値によって試験を行うのは実際上程
々の制約を伴うため、それより低い試験電圧(例えば最
高1.25E/fiの電圧)によって劣化の判定を行え
ることが望ましく、その方法として我国では損失角試験
、電流特性試験、部分放電試験の三種類の試験の結果か
ら絶縁劣化の程度の判定を行う方法が広く実用されてい
る。In this case, carrying out the test using the above-mentioned voltage value is actually quite restrictive, so it is desirable to be able to judge the deterioration using a lower test voltage (for example, a maximum voltage of 1.25E/fi). In Japan, a method is widely used in which the degree of insulation deterioration is determined from the results of three types of tests: loss angle test, current characteristic test, and partial discharge test.
ところで方法の第1である損失角、電流を利用する方法
は、絶縁劣化にもとづき巻線の絶縁部の内部に生ずる間
隙部において発生する部分放電、所謂ボイド放電による
損失の増大にもとづく損失角、交流電流の増加率(Jt
anδ)、(JI)を判定項目とするものである。By the way, the first method, which uses the loss angle and current, is based on the loss angle, which is based on the increase in loss due to partial discharge, so-called void discharge, that occurs in the gap inside the insulated part of the winding due to insulation deterioration. Rate of increase in alternating current (Jt
and (JI) as the determination items.
また部分放電試験によるものは、電荷が電圧に比例(Q
=CV)するのを利用して、絶縁劣化の目安となるボイ
ド放電時発生する放電パルスの最大電圧値から放電電荷
Qamax(これを一般には最大放電電荷と称している
。In addition, in partial discharge tests, the charge is proportional to the voltage (Q
=CV), the discharge charge Qamax (this is generally referred to as the maximum discharge charge) is calculated from the maximum voltage value of the discharge pulse generated during void discharge, which is a measure of insulation deterioration.
)を求め、これを判定項目とするものであって、これら
の方法は前記損失角の増加率(Jtanδ)、電流の増
加率(JI)、最大放電電荷(Qamax)を、供試固
定子巻線と同一絶縁階級、同一電圧階級の多数の固定子
巻線について求められた判定規準値(JtanδS)、
(JIs)、(Qamaxs )と照合し、判定規準値
に対する大小から劣化の状態を判定するものである。) and use this as the judgment item. These methods calculate the rate of increase in loss angle (Jtanδ), rate of increase in current (JI), and maximum discharge charge (Qamax) for the stator winding under test. Judgment standard value (Jtan δS) obtained for a large number of stator windings of the same insulation class and the same voltage class as the line,
(JIs) and (Qamaxs), and the state of deterioration is determined based on the magnitude relative to the determination standard value.
しかしこれら従来の方法では判定結果に相異を来すこと
があり、特に最大放電電荷による方法は他の2法と差を
生ずることが多い。However, these conventional methods may produce different judgment results, and in particular, the method using the maximum discharge charge often produces differences from the other two methods.
従って3種の結果を総合して判定を行うが、これでも第
1表中(後記)に示す発電機Cの結果のように絶縁耐力
試験によって得られた結果と相異することがあり、未だ
充分な信頼性を得るに至っていない。Therefore, a judgment is made by integrating the three types of results, but even this may differ from the results obtained by the dielectric strength test, such as the results for generator C shown in Table 1 (see below), and there are still cases where It has not yet achieved sufficient reliability.
本発明は最大放電電荷を判定項目とする方法を利用して
固定子巻線の絶縁劣化を高い確度をもって判定し得る方
法を提供し、信頼性の向上を図ったものである。The present invention aims to improve reliability by providing a method for determining insulation deterioration of stator windings with high accuracy using a method using maximum discharge charge as a determination item.
次に詳細に説明する。本発明者の研究によれば、従来方
法の判定結果と実際の絶縁耐力の結果とが相異する主た
る理由は、固定子巻線の表面に発生する放電所謂沿面放
電にもとづくものであることが明らかにされた。This will be explained in detail next. According to the research conducted by the present inventors, the main reason for the difference between the judgment results of the conventional method and the actual dielectric strength results is due to the so-called creeping discharge that occurs on the surface of the stator winding. revealed.
固定子巻線表面における放電の発生は発電機が製作され
た当初においては、例えば放電防止塗料の塗布によって
防止されているが、年を経るに従いその効果は次第に薄
れ、しかもその程度は発電機の使用状況などによって異
ってくる。When the generator was first manufactured, the occurrence of electrical discharge on the stator winding surface was prevented, for example, by applying anti-discharge paint, but as the years passed, this effect gradually faded, and the extent of this was limited by the It varies depending on usage conditions, etc.
このため損失角、電流の増加率を判定項目とする方法で
は、それだけ損失が犬となって判定結果を悲観的な方向
に傾むけ、また判定結果のばらつきを生じさせる。For this reason, in a method in which the loss angle and the rate of increase in current are used as judgment items, the loss increases accordingly, tilting the judgment results in a pessimistic direction and causing variations in the judgment results.
また前記のように放電パルス電圧値から求めた最大放電
電荷を判定項目とする部分放電試験による方法では、沿
面放電による放電電荷量がボイド放電による最大放電電
荷量を上廻るような場合には、検出された最大放電電荷
は沿面放電によるものを示すことになるので、この場合
沿面放電の影響は増加率を判定項目とするものに比べて
遥かに大きくなり、劣化判定に当って他の三者と相異を
生じさせる結果となる。In addition, in the partial discharge test method in which the maximum discharge charge determined from the discharge pulse voltage value is used as a judgment item as described above, if the amount of discharge charge due to creeping discharge exceeds the maximum discharge charge amount due to void discharge, The maximum discharge charge detected indicates that due to creeping discharge, so in this case the influence of creeping discharge is much greater than when the increase rate is the criterion item, and the other three factors are not considered when determining deterioration. This results in a difference.
本発明は最大放電電荷を判定項目とする劣化判定の方法
において、ボイド放電と沿面放電の性状の相異を利用す
ることにより、沿面放電による影響を回避して判定の確
度を向上しうろことを着想してなされたものである。The present invention aims to avoid the influence of creeping discharge and improve the accuracy of the determination by utilizing the difference in the properties of void discharge and creeping discharge in a method of determining deterioration in which the maximum discharge charge is the criterion item. It was conceived and done.
ボイド放電は絶縁劣化の原因となる巻線内部の空隙、即
ち閉塞空間において発生するものであるので、一旦放電
を生じた場合には試験電圧が上昇しても、放電自体はそ
れ以上発展せず放電回数が増大するのみである。Void discharge occurs in the void inside the winding, that is, in a closed space, which causes insulation deterioration, so once a discharge occurs, the discharge itself will not develop any further even if the test voltage increases. The number of discharges only increases.
従って仮に複数個の空隙の空隙長が同一であるとした場
合には試験電圧と最大放電電荷の関係は第1図aに示す
実線の如くなり、また空隙長が小となるに伴い最大放電
電荷は図中点線のように変化する(空隙長が小さくなる
と放電電圧は下がるが、絶縁体が充実した状態になるの
で絶縁体の分担電圧は高くなり、放電開始電圧は上がる
)。Therefore, if the gap lengths of multiple gaps are the same, the relationship between the test voltage and the maximum discharge charge will be as shown by the solid line shown in Figure 1a, and as the gap length becomes smaller, the maximum discharge charge changes as shown by the dotted line in the figure (as the gap length decreases, the discharge voltage decreases, but as the insulator becomes more complete, the voltage shared by the insulator increases, and the discharge starting voltage increases).
また空隙長の異なる空隙が複数個存在する実巻線では空
隙長が小さいものから放電するから最大放電電荷値は第
1図a中の一点鎖線のように変化する。Furthermore, in a real winding wire in which there are a plurality of gaps having different gap lengths, discharge occurs from the one with the smallest gap length, so the maximum discharge charge value changes as shown by the dashed-dotted line in FIG. 1a.
−力漕面放電は開放空間における放電であるので、試験
電圧の上昇と共に次第に発展して第1図すのように最大
放電電荷が次第に犬となる傾向を呈する。- Since the surface discharge is a discharge in an open space, it gradually develops as the test voltage increases, and the maximum discharge charge tends to gradually become smaller as shown in FIG.
しかも一般に試験電圧が高くなるに伴い放電は急速な広
がりを見せ、沿面放電にもとづく最大放電電荷がボイド
放電による最大放電電荷を上廻るケースは、最高試験電
圧の附近において発生する。Furthermore, discharge generally spreads rapidly as the test voltage increases, and cases in which the maximum discharge charge due to creeping discharge exceeds the maximum discharge charge due to void discharge occur near the highest test voltage.
これらの事実は、判定に当って従来のように沿面放電に
よる影響を受けるおそれの多い、最高試験電圧値に近い
ところの一点の最大放電電荷のみに着目するのではなく
、ボイド放電の発生している電圧領域全域の最大放電電
荷の挙動に着目して判定すれば沿面放電による影響を少
なく判定できることを示唆している。These facts mean that when making judgments, instead of focusing only on the maximum discharge charge at a point near the highest test voltage value, which is likely to be affected by creeping discharge, as in the past, This suggests that it is possible to reduce the influence of creeping discharge by focusing on the behavior of the maximum discharge charge over the entire voltage range.
本発明は最大放電電荷と試験電圧の対数をそれぞれとり
、両者の関係を目盛紙上に図示することにより、上記関
係曲線を直線でほぼ近似しうろことを見出し、また最高
試験電圧をiooφ、最高試験電圧における最大放電電
荷を100%表示し、関係曲線の原点を最高試験電圧点
としたとき、前記したボイド放電と沿面放電の性状の差
から関係曲線が第2図の傾向を呈し、ボイド放電が発生
する領域における関係曲線の傾斜度を判定基準曲線の傾
斜度と照合することによって確度高く判定できることを
着想したものである。The present invention calculates the logarithm of the maximum discharge charge and the test voltage, and plots the relationship between the two on a scale paper, thereby approximating the above relationship curve with a straight line and finding a scale. When the maximum discharge charge at voltage is expressed as 100% and the origin of the relational curve is taken as the highest test voltage point, the relational curve exhibits the tendency shown in Figure 2 due to the difference in the properties of void discharge and creeping discharge as described above, indicating that void discharge The idea is that a highly accurate determination can be made by comparing the slope of the relational curve in the region where the problem occurs with the slope of the determination reference curve.
第2図は絶縁耐力が運転に耐えられないA発電機と、こ
れより絶縁耐力は高いがやはり運転に耐えられないB発
電機、運転に耐えられる絶縁耐力をもつC発電機、およ
びC発電機より更に絶縁耐力の高いD発電機を用いて、
最大放電電荷と試験電圧の関係を実測した結果である。Figure 2 shows generator A whose dielectric strength cannot withstand operation, generator B which has a higher dielectric strength but still cannot withstand operation, generator C whose dielectric strength can withstand operation, and generator C. Using a D generator with even higher dielectric strength,
This is the result of actually measuring the relationship between the maximum discharge charge and the test voltage.
この図を見て明らかな如く、絶縁耐力が不良即ちボイド
放電による最大放電電荷量が大きいA関係曲線において
、沿線放電による最大放電電荷が上廻り、部分的に曲線
の傾斜度が大となっても(A曲線のA1部分参照)、関
係曲線としては最高試験電圧点01とボイド放電発生点
02とを結んだ直線の傾斜度と殆ど近似する。As is clear from this figure, in the A-related curve where the dielectric strength is poor, that is, the maximum discharge charge due to void discharge is large, the maximum discharge charge due to lineside discharge exceeds it, and the slope of the curve becomes large in some parts. (see A1 section of curve A), the relational curve almost approximates the slope of the straight line connecting the highest test voltage point 01 and the void discharge generation point 02.
またこの傾向は他の曲線についても同様にいえることか
ら、本発明のように関係曲線を表示することにより沿面
放電による影響を少なくできることを示している。Furthermore, this tendency can be said to be true for other curves as well, which indicates that the influence of creeping discharge can be reduced by displaying related curves as in the present invention.
しかも関係曲線の傾斜の度合は最大放電電荷の大きいも
の程緩やかとなる傾向を示す。Moreover, the degree of slope of the relational curve tends to become gentler as the maximum discharge charge becomes larger.
従ってこの傾斜の度合を多数の巻線を用いて予め作られ
た判定基準曲線Sと照合し、例えば供試発電機の関係曲
線が基準曲線の右側に位置するか、或いは左側に位置す
るかを知れば劣化の判定を容易に行うことができる。Therefore, the degree of this inclination is compared with a judgment standard curve S prepared in advance using a large number of windings, and it can be determined, for example, whether the relational curve of the test generator is located on the right side or the left side of the standard curve. If you know this, you can easily judge the deterioration.
また関係曲線の原点01とボイド放電発生点02を結ぶ
直線の傾斜の度合Qnは
ただし vx:関係曲線の直線領域における試験電圧
Q a m a x v z :試験電圧vxにおける
最大放電電荷で表わされるから、これによって計算され
た各関係曲線の傾斜度Qnと、予め作られた判定基準直
線Sの傾斜度Qsとを数値的に照合し、Qsからの大小
を求めれば劣化を判定できる。In addition, the degree of inclination Qn of the straight line connecting the origin 01 of the relational curve and the void discharge generation point 02 is expressed as follows: vx: test voltage in the linear region of the relational curve Q a m a x vz: maximum discharge charge at the test voltage vx Therefore, deterioration can be determined by numerically comparing the slope Qn of each relational curve thus calculated with the slope Qs of the determination reference straight line S created in advance and determining the magnitude from Qs.
第1表は上記した本発明方法による発電機A、B、Cお
よびDの判定結果を絶縁耐力試験によって求めた結果と
を対比したものである。Table 1 compares the determination results of generators A, B, C, and D according to the method of the present invention described above with the results determined by the dielectric strength test.
これから明らかなように判定結果は絶縁耐力試験の結果
と全く一致している。As is clear from this, the judgment results are completely consistent with the results of the dielectric strength test.
なお第2図の関係曲線の傾斜度QnはA発電機が0.5
4、Bが1.25、Cが2.8、Dが3.8であり、判
定基準となる傾斜度は1.5が妥当であった。Incidentally, the slope Qn of the relational curve in Fig. 2 is 0.5 for generator A.
4, B was 1.25, C was 2.8, and D was 3.8, and the slope used as the criterion was 1.5.
次に本発明の原理による簡単な判定装置の一例を第3図
によって説明する。Next, an example of a simple determination device based on the principles of the present invention will be explained with reference to FIG.
第3図において1は誘導電圧調整器、2は試験用高圧変
圧器、2aはその1次巻線、2bは2次巻線、2cは3
次巻線、3は供試発電機の固定子巻線、4は放電による
パルス電圧を検出する結合コンデンサ、5は交流分を除
去するバイパスフィルタ、6 a > 6 bは対数変
換用の非線形増幅器、7はX−Yレコーダである。In Figure 3, 1 is an induced voltage regulator, 2 is a high voltage transformer for testing, 2a is its primary winding, 2b is its secondary winding, and 2c is 3
The next winding, 3 is the stator winding of the generator under test, 4 is the coupling capacitor that detects the pulse voltage due to discharge, 5 is the bypass filter that removes the alternating current component, 6 a > 6 b is the nonlinear amplifier for logarithmic conversion , 7 is an X-Y recorder.
この装置においては誘導電圧調整器1による1次巻線2
aの供給電圧の調整により、固定子巻線3の一端と対地
間に2次巻線2bの出力電圧が加えられる。In this device, the primary winding 2 by the induced voltage regulator 1
By adjusting the supply voltage of a, the output voltage of the secondary winding 2b is applied between one end of the stator winding 3 and the ground.
課電により生じた放電により巻線端に生じた放電パルス
は結合コンデンサ4によって検出され、バイパスフィル
タ5により交流分を除去されて対数変換用の非線形増幅
器6aに入り、ここで圧縮増幅されて直流に変換される
。The discharge pulse generated at the end of the winding due to the discharge caused by the application of electricity is detected by the coupling capacitor 4, and the AC component is removed by the bypass filter 5, and then enters the nonlinear amplifier 6a for logarithmic conversion, where it is compressed and amplified to convert it into DC. is converted to
従ってその出力側には対数化された最大放電電荷に相当
する直流出力が送出され、この出力はX−Yレコーダ7
のY軸入力端子に加えられる。Therefore, a DC output corresponding to the logarithmized maximum discharge charge is sent to the output side, and this output is sent to the X-Y recorder 7.
is added to the Y-axis input terminal of
一方変圧器2の3次巻線電圧は対数変換用の非線形増幅
器部に入り、放電パルスと同様に圧縮増幅され更に直流
変換される。On the other hand, the tertiary winding voltage of the transformer 2 enters a nonlinear amplifier section for logarithmic conversion, is compressed and amplified in the same way as the discharge pulse, and is further converted into DC.
従ってその出力側には対数化された試験電圧に相当する
直流出力が送出され、この出力はX−Yレコーダ7のX
軸入力端子に加えられろうそこで今誘導電圧調整器1に
より変圧器2の2次巻線電圧を最高試験電圧とし、対数
変換用非線形増幅器6a + 6bの出力調整装置を調
整して、最高試験電圧における最大放電電荷をX−Yレ
コーダ7の目盛紙7aのY軸の1oo%目盛に合わせ、
また最高試験電圧をX軸目盛の1001%に合わせて、
試験電圧を順次降下させる。Therefore, a DC output corresponding to the logarithmized test voltage is sent to the output side of the X-Y recorder 7.
Then, the secondary winding voltage of the transformer 2 is set to the maximum test voltage by the induction voltage regulator 1, and the output adjustment device of the logarithmic conversion nonlinear amplifier 6a + 6b is adjusted to the maximum test voltage. Adjust the maximum discharge charge at the 10% scale on the Y axis of the scale paper 7a of the X-Y recorder 7,
Also, set the maximum test voltage to 1001% on the X-axis scale,
The test voltage is gradually lowered.
するとX−Yレコーダ7の目盛紙上には最高放電電荷と
試験電圧の関係曲線が画かれる。Then, a relationship curve between the maximum discharge charge and the test voltage is drawn on the scale paper of the X-Y recorder 7.
そこで予め目盛紙上に記された判定基準線と照合すれば
、傾斜度を計算するような面倒な操作を必要とすること
なく、簡単に絶縁劣化の判定を行うことができる。Therefore, by comparing the reference line marked on the scale paper in advance, insulation deterioration can be easily determined without the need for troublesome operations such as calculating the degree of inclination.
なおこの場合ブラウン表示器を用いうろことはいうまで
もない。In this case, it goes without saying that a brown indicator is used.
以上の説明から明らかなように、本発明によれば部分放
電試験によって発電機などの回転機の固定子巻線の絶縁
耐力の劣化程度を確度高く判定できるすぐれた利点を有
するもので、発電機などの保守管理上における効果には
著しいものがある。As is clear from the above description, the present invention has an excellent advantage in that the degree of deterioration of the dielectric strength of the stator winding of a rotating machine such as a generator can be determined with high accuracy through a partial discharge test. The effects on maintenance management are remarkable.
第1図a、bは発電機固定子巻線におけるボイド放電時
と沿面放電時における最大放電電荷と印加電圧の関係を
示す図、第2図は本発明を説明するための両対数目盛上
に多表示した最大放電電荷と試験電圧の関係図、第3図
は本発明による絶縁劣化判定装置の回路図である。Figures 1a and b are diagrams showing the relationship between the maximum discharge charge and applied voltage during void discharge and creeping discharge in the generator stator winding, and Figure 2 is a graph on a logarithmic scale for explaining the present invention. FIG. 3 is a diagram illustrating the relationship between the maximum discharge charge and the test voltage displayed in multiple numbers, and is a circuit diagram of the insulation deterioration determination device according to the present invention.
Claims (1)
関係曲線の傾きの度合を判定基準曲線の傾きの度合と照
合して、巻線が運転に必要な絶縁耐力を有するか否かを
判定することを特徴とする回転機固定子巻線の絶縁劣化
判定方法。1 Check whether the winding has the dielectric strength necessary for operation by comparing the slope of the relationship curve between the logarithmically displayed maximum discharge charge and the test voltage with the slope of the judgment standard curve. A method for determining insulation deterioration of a stator winding of a rotating machine.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP51032751A JPS5829873B2 (en) | 1976-03-25 | 1976-03-25 | Method for determining insulation deterioration of rotating machine stator windings |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP51032751A JPS5829873B2 (en) | 1976-03-25 | 1976-03-25 | Method for determining insulation deterioration of rotating machine stator windings |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS52115303A JPS52115303A (en) | 1977-09-27 |
JPS5829873B2 true JPS5829873B2 (en) | 1983-06-25 |
Family
ID=12367540
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP51032751A Expired JPS5829873B2 (en) | 1976-03-25 | 1976-03-25 | Method for determining insulation deterioration of rotating machine stator windings |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS5829873B2 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPWO2020105557A1 (en) * | 2018-11-20 | 2021-09-27 | 三菱電機プラントエンジニアリング株式会社 | Remaining life diagnosis method for rotary electric machines and remaining life diagnosis device for revolving electric machines |
-
1976
- 1976-03-25 JP JP51032751A patent/JPS5829873B2/en not_active Expired
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPWO2020105557A1 (en) * | 2018-11-20 | 2021-09-27 | 三菱電機プラントエンジニアリング株式会社 | Remaining life diagnosis method for rotary electric machines and remaining life diagnosis device for revolving electric machines |
Also Published As
Publication number | Publication date |
---|---|
JPS52115303A (en) | 1977-09-27 |
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