JP2871075B2 - Insulation diagnostic circuit and device - Google Patents
Insulation diagnostic circuit and deviceInfo
- Publication number
- JP2871075B2 JP2871075B2 JP2315594A JP31559490A JP2871075B2 JP 2871075 B2 JP2871075 B2 JP 2871075B2 JP 2315594 A JP2315594 A JP 2315594A JP 31559490 A JP31559490 A JP 31559490A JP 2871075 B2 JP2871075 B2 JP 2871075B2
- Authority
- JP
- Japan
- Prior art keywords
- voltage
- power supply
- insulation
- transformer
- test
- 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
- 238000009413 insulation Methods 0.000 title description 25
- 239000012212 insulator Substances 0.000 claims description 15
- 230000006866 deterioration Effects 0.000 claims description 13
- 239000003990 capacitor Substances 0.000 claims description 10
- 230000000903 blocking effect Effects 0.000 claims description 4
- 238000003745 diagnosis Methods 0.000 description 8
- 238000010586 diagram Methods 0.000 description 5
- 230000015556 catabolic process Effects 0.000 description 4
- 239000007789 gas Substances 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000007689 inspection Methods 0.000 description 2
- 230000001737 promoting effect Effects 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 101100115156 Caenorhabditis elegans ctr-9 gene Proteins 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- -1 magnetism Substances 0.000 description 1
- 230000005389 magnetism Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 229920013716 polyethylene resin Polymers 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Testing Relating To Insulation (AREA)
Description
【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION
この発明は、高電圧用として使用されている開閉器、
変圧器、コンデンサ、或いは電力ケーブル等の絶縁診断
をするための装置に関する。The present invention relates to a switch used for high voltage,
The present invention relates to a device for performing insulation diagnosis of a transformer, a capacitor, a power cable, or the like.
従来、高電圧用として使用されている開閉器、変圧
器、コンデンサ、電力ケーブル等（総称して、高電圧機
器という。）について絶縁診断をしようとする場合は、
それら高電圧機器に直流高電圧を課電し、その時、当該
高電圧機器の劣化部分に発生する漏れ電流を測定するこ
とで診断している。Conventionally, when performing insulation diagnosis for switches, transformers, capacitors, power cables, etc. (collectively referred to as high-voltage equipment) that have been used for high voltage,
DC high voltage is applied to these high-voltage devices, and at that time, diagnosis is performed by measuring a leakage current generated in a deteriorated portion of the high-voltage devices.
しかしながら、上記手法で高電圧機器の絶縁診断を実
施した場合、往々にして課電した直流高電圧によって高
電圧機器を絶縁破壊させてしまったり、高電圧機器の劣
化部分に直流電集の残留電荷が残り検査終了時に接地し
た際、残留電荷によって劣化部分に電気トリーを発生さ
せてしまって、その結果絶縁劣化を更に促進させてしま
い、検査終了後に再び交流使用電圧を印加した際に絶縁
体を破壊に至らしめしまう事がある等の問題がある。 このように、従来は、高電圧機器の絶縁診断のため当
該機器を絶縁破壊させてしまい、その復旧に長時間に亘
って停電を余儀無くされたり、本来軽度であった絶縁劣
化を徒に促進させてしまうと言った問題があった。 従って、この発明は、上記した従来技術の問題点を解
消して高電圧機器の絶縁診断ができる装置の提供を目的
とする。However, when the insulation diagnosis of high-voltage equipment is performed by the above method, the high-voltage equipment often causes insulation breakdown of the high-voltage equipment, or the residual charge of the DC current collector is deteriorated in the high-voltage equipment. When grounding is performed at the end of the remaining inspection, electric trees are generated in the deteriorated portion due to residual charges, and as a result, insulation deterioration is further promoted, and the insulator is destroyed when the AC working voltage is applied again after the inspection is completed And so on. As described above, conventionally, the insulation of a high-voltage device has been broken down due to the insulation diagnosis, and a power outage has been forced for a long time to recover the device, and the insulation deterioration, which was originally mild, has been promoted. There was a problem that said. Accordingly, an object of the present invention is to provide an apparatus capable of solving the above-mentioned problems of the prior art and performing insulation diagnosis of high-voltage equipment.
即ち、この発明は、被測定体である高電圧機器に交流
常規電圧を印加する試験用交流トランスと、上記試験用
交流トランスの２次コイル低電圧側と大地間に設置され
た交流電流通過用コンデンサと、上記交流電流通過用コ
ンデンサと並列に接続された保護抵抗（もしくはブロッ
キングコイル）、直流電圧重畳用電源、及び上記高電圧
機器の絶縁体の劣化に伴って発生するシグナルである直
流成分を測定する直流成分測定装置とからなり、上記直
流電圧重畳用電源には印加する直流電圧の極性を切り換
えるスイッチ及び当該電源を回路から電気的に切り離す
スイッチが備えられてなることを特徴として構成された
ものである。That is, the present invention provides a test AC transformer for applying an AC normal voltage to a high-voltage device which is a device under test, and an AC current passing between a low voltage side of a secondary coil of the test AC transformer and the ground. A capacitor, a protection resistor (or a blocking coil) connected in parallel with the AC current passing capacitor, a DC voltage superimposing power supply, and a DC component which is a signal generated due to deterioration of an insulator of the high voltage device. And a switch for switching the polarity of a DC voltage to be applied and a switch for electrically disconnecting the power supply from the circuit. Things.
この発明の絶縁診断装置を用いれば、試験用交流トラ
ンスを通じて高電圧機器に交流常規電圧を課電した時に
当該機器の絶縁劣化部分を通して発生する直流成分と、
上記交流常規上記電圧に直流電圧重畳用電源を通して直
流電圧をバイアスして上記直流成分を測定することで、
交流課電によって活性化した上記高電圧機器の絶縁体か
らの絶縁劣化シグナル（直流成分）を直流電圧の重畳に
より増大させて測定できるので、上記絶縁体の絶縁破壊
を防止しつつ、また絶縁体の劣化を徒に促進させること
もなく、高電圧機器の絶縁劣化の状態を確実に診断でき
る。With the use of the insulation diagnostic device of the present invention, a DC component generated through an insulation-degraded portion of the high-voltage device when an AC normal voltage is applied to the high-voltage device through a test AC transformer,
By measuring the DC component by biasing a DC voltage to the AC normal voltage through a DC voltage superimposing power supply,
Since the insulation deterioration signal (DC component) from the insulator of the high-voltage device activated by the AC application can be increased and measured by superimposing a DC voltage, the insulation breakdown of the insulator can be prevented and the insulator can be prevented. It is possible to surely diagnose the state of insulation deterioration of high-voltage equipment without promoting deterioration of the insulation.
以下、この発明の実施例を図面を参照して説明する。 第１図及び第２図は、この発明に係る絶縁診断装置の
実施例を示すブロック回路図である。 第１図おいて、１は交流常規電圧を課電するための試
験用交流トランスで、２はその２次コイル低電圧側と大
地間に設置された交流電流通過用コンデンサである。1
4,5,7はそれぞれ上記コンデンサ２に並列に接続された
保護抵抗，直流電圧重畳用電源，直流成分測定装置であ
る。４は直流電圧重畳用電源５を上記交流電流通過用コ
ンデンサ２→保護抵抗14→直流成分測定装置７の回路か
ら電気的に分離するスイッチであり、このスイッチ４を
ONにすることで上記電源５は上記回路から電気的に分離
され、このスイッチ４をOFFにすることで上記電源５は
上記回路に電気的接続される。即ち、上記スイッチ４を
OFFにすることで、試験用交流トランス１を通じて後述
の高電圧機器に交流常規電圧を課電した時に当該機器の
絶縁劣化部分から発生する劣化シグナルである直流成分
が上記装置７で測定でき、このスイッチ４をONにするこ
とで直流電圧重畳用電源５を通して直流電圧をバイアス
して上記直流成分を測定することができる。６は上記直
流電圧重畳用電源５から印加する直流電圧の極性を切り
換えるスイッチである。なお、上記直流電圧重畳用電源
５から印加する直流電圧をどの程度とすればよいか、ま
た、その直流電圧の極性を切り換えることの理由等につ
いては、本出願人が左に出願し既に公知となっている特
開昭59−202073号公報に詳しく記載されているので、そ
れを参照されたい。 12は被測定体である高電圧機器（電力ケーブル）であ
り、11は上記試験用交流トランス１の２次コイル高電圧
側と高電圧機器12間を接続するリードケーブルである。 ８は上記直流成分測定装置７に接続されたCPUで、当
該測定装置７で測定された直流成分を記憶し、この記憶
したデータを処理して、CTR9に表示すると共にプリンタ
10でプリントアウトする。 第２図は、第１図おいて用いられた保護抵抗14に代え
てブロッキングコイル15を用いた他の実施例である。 第３図は、第１図及び第２図に示す実施例において用
いられた試験交流トランス１の具体的構成図である。 この図において、２次コイル22はサポート絶縁物21
（例えば、含水性のない磁気、セラミック、ポリエチレ
ン樹脂、エポキシ樹脂等の高体電圧材で構成されてい
る。）の上に設置されている。１次コイル24は上記２次
コイル22の周りにコイル絶縁物23を介して設けられてい
る。この２次コイル22の高電圧側は高電圧ブッシング25
に接続され、低電圧側は低電圧ブッシング28に接続され
る。２次コイル低電圧側22と低電圧ブッシング28の間の
接続線26には絶縁被覆が施されている。１次コイル24と
電源ブッシング31の間の接続は、２次コイル22と低電圧
ブッシング28の間の接続線26と一定以上の距離を持たせ
て構成することで絶縁されている。高電圧ブッシング25
と低電圧ブッシング28には、それぞれケーブル30が接続
されている。このケーブル30にはそれぞれストレスコー
ン27が設けられて絶縁補強がなされている。 そして、筐体33内には絶縁油（OF油等）32等が充填さ
れている。なお、筐体33内に絶縁油32が充填されるに先
立って、筐体33内は例えば90℃の高温下で1/100mmHg以
下の気圧になるまで脱気用真空引きポンプで脱気され、
筐体33内部が十分に脱気されたところで絶縁油32が注入
充填される。 さらに、試験用交流トランス１には、絶縁油32の温度
膨張を吸収するためのガス室29が筐体33の上部に設けら
れている。このガス室29内部は、0.2〜0.5kg/cm2Gの乾
燥した窒素等の不活性ガスを充填した状態で密閉されて
いる。 こうして、１次コイル24と２次コイル22の間、及び２
次コイル22と筐体33の間に高度な絶縁抵抗を備えた試験
用交流トランス１が構成される。 上記試験用交流トランス１の２次コイル22の高電圧側
に接続された高電圧ブッシング25を通じて被測定体であ
る高電圧機器12に交流常規電圧を課電しながら、２次コ
イル22の低電圧側に接続された低電圧ブッシング28を通
じて交流常規電圧課電時の直流成分を測定することで、
当該高電圧機器12の絶縁体からの絶縁劣化シグナル（直
流成分）を検知できる。Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIGS. 1 and 2 are block circuit diagrams showing an embodiment of the insulation diagnostic apparatus according to the present invention. In FIG. 1, reference numeral 1 denotes a test AC transformer for applying an AC normal voltage, and reference numeral 2 denotes an AC current passing capacitor provided between the secondary coil low voltage side and the ground. 1
Reference numerals 4, 5, and 7 denote a protection resistor, a DC voltage superimposing power supply, and a DC component measuring device connected in parallel to the capacitor 2, respectively. Reference numeral 4 denotes a switch for electrically separating the DC voltage superimposing power supply 5 from the AC current passing capacitor 2 → protective resistor 14 → DC component measuring device 7 circuit.
Turning on the switch electrically disconnects the power supply 5 from the circuit, and turning off the switch 4 electrically connects the power supply 5 to the circuit. That is, the switch 4
By turning OFF, the DC component which is a deterioration signal generated from the insulation deterioration portion of the high voltage equipment described later when the AC normal voltage is applied through the test AC transformer 1 can be measured by the device 7, When the switch 4 is turned on, the DC voltage can be biased through the DC voltage superimposing power supply 5 to measure the DC component. A switch 6 switches the polarity of the DC voltage applied from the DC voltage superimposing power supply 5. It should be noted that the level of the DC voltage to be applied from the DC voltage superimposing power supply 5 and the reason for switching the polarity of the DC voltage, etc., are filed by the present applicant on the left and are already known. For details, refer to Japanese Patent Application Laid-Open No. 59-202073. Reference numeral 12 denotes a high-voltage device (power cable) as an object to be measured, and reference numeral 11 denotes a lead cable for connecting the high voltage side of the secondary coil of the test AC transformer 1 to the high-voltage device 12. Reference numeral 8 denotes a CPU connected to the DC component measuring device 7, which stores the DC component measured by the measuring device 7, processes the stored data, displays the data on the CTR 9, and displays the data on the printer.
Print out with 10. FIG. 2 shows another embodiment in which a blocking coil 15 is used in place of the protection resistor 14 used in FIG. FIG. 3 is a specific configuration diagram of the test AC transformer 1 used in the embodiment shown in FIG. 1 and FIG. In this figure, the secondary coil 22 is a support insulator 21
(For example, it is made of a high-voltage material such as magnetism, ceramic, polyethylene resin, epoxy resin, etc., which does not contain water.) The primary coil 24 is provided around the secondary coil 22 via a coil insulator 23. The high voltage side of the secondary coil 22 is connected to a high voltage bushing 25.
And the low voltage side is connected to a low voltage bushing 28. The connecting wire 26 between the secondary coil low voltage side 22 and the low voltage bushing 28 is provided with an insulating coating. The connection between the primary coil 24 and the power supply bushing 31 is insulated by providing a connection line 26 between the secondary coil 22 and the low-voltage bushing 28 with a certain distance or more. High voltage bushing 25
And a low voltage bushing 28, a cable 30 is connected to each. Each of the cables 30 is provided with a stress cone 27 for insulation reinforcement. The casing 33 is filled with insulating oil (OF oil or the like) 32 or the like. Prior to filling the casing 33 with the insulating oil 32, the inside of the casing 33 is deaerated by a deaeration vacuum pump at a high temperature of 90 ° C. until the pressure becomes 1/100 mmHg or less, for example.
When the inside of the housing 33 is sufficiently degassed, the insulating oil 32 is injected and filled. Further, a gas chamber 29 for absorbing the thermal expansion of the insulating oil 32 is provided in the upper part of the housing 33 in the test AC transformer 1. The inside of the gas chamber 29 is sealed in a state filled with 0.2 to 0.5 kg / cm 2 G of an inert gas such as dry nitrogen. Thus, between the primary coil 24 and the secondary coil 22, and
The test AC transformer 1 having a high insulation resistance is configured between the secondary coil 22 and the housing 33. A high voltage bushing 25 connected to a high voltage side of the secondary coil 22 of the test AC transformer 1 applies an AC normal voltage to the high voltage device 12 as a device under test while the low voltage of the secondary coil 22 is applied. By measuring the DC component at the time of applying the AC normal voltage through the low voltage bushing 28 connected to the side,
An insulation deterioration signal (DC component) from the insulator of the high-voltage device 12 can be detected.
以上説明したとおり、この発明の絶縁診断装置を用
い、交流電圧課電によって活性化した状態で高電圧機器
12の絶縁体の劣化に伴って発生した微弱なシグナル（直
流成分）に対し、直流電圧をバイアスすることで、上記
シグナルを増大させて測定することができ、また、この
時のシグナル（直流成分）の増大量の大小によって上記
絶縁体の劣化状態を判定できる。 従って、この発明の絶縁診断装置を用いれば、従来の
手法（高電圧機器に直流高電圧を課電し、その時、当該
高電圧機器の劣化部分に発生する漏れ電流を測定するこ
とで診断を行う手法。）における諸々の問題を一掃でき
る。その結果、高電圧機器12の絶縁体の絶縁破壊を防止
し、さらに絶縁体の劣化を促進させることもなく、高電
圧機器12の絶縁劣化の状態を確実に診断できる。As described above, using the insulation diagnostic apparatus of the present invention, a high-voltage device activated by an AC voltage application
By biasing the DC voltage against the weak signal (DC component) generated due to the deterioration of the insulator in Fig. 12, the above signal can be increased and measured, and the signal (DC component) The deterioration state of the insulator can be determined based on the magnitude of the increase in ()). Therefore, by using the insulation diagnosis apparatus of the present invention, diagnosis is performed by applying a DC high voltage to a high-voltage device and measuring a leakage current generated in a deteriorated portion of the high-voltage device at that time. Method)). As a result, insulation breakdown of the insulator of the high-voltage device 12 can be prevented, and the state of insulation degradation of the high-voltage device 12 can be diagnosed without promoting deterioration of the insulator.
【第１図】 本発明の実施例のブロック回路の構成を示す回路図であ
る。FIG. 1 is a circuit diagram showing a configuration of a block circuit according to an embodiment of the present invention.
【第２図】 本発明の他の実施例のブロック回路の構成を示す回路図
である。FIG. 2 is a circuit diagram showing a configuration of a block circuit according to another embodiment of the present invention.
【第３図】 本発明の実施例において用いられる試験用交流トランス
の具体例を示す説明図である。FIG. 3 is an explanatory diagram showing a specific example of a test AC transformer used in an embodiment of the present invention.
１……試験用交流トランス ２……交流電流通過用コンデンサ ４……直流電圧重畳用電源を分離するスイッチ ５……直流電圧重畳用電源 ６……直流電圧の極性を切り換えるスイッチ ７……直流成分測定装置 ８……CPU ９……CRT 10……プリンタ 11……リードケーブル 12……高電圧機器 14……保護抵抗 15……ブロッキングコイル 21……サポート絶縁物 22……２次コイル 23……コイル絶縁物 24……１次コイル 25……高電圧ブッシング 26……接続線 27……ストレスコーン 28……低電圧ブッシング28 29……ガス室 30……ケーブル 31……電源ブッシング 32……絶縁油 33……筐体 DESCRIPTION OF SYMBOLS 1 ... AC transformer for test 2 ... Capacitor for passing AC current 4 ... Switch for separating the power supply for DC voltage superposition 5 ... Power supply for DC voltage superposition 6 ... Switch for switching the polarity of DC voltage 7 ... DC component Measuring device 8 CPU 9 CRT 10 Printer 11 Lead cable 12 High-voltage equipment 14 Protective resistor 15 Blocking coil 21 Support insulator 22 Secondary coil 23 Coil insulator 24 Primary coil 25 High voltage bushing 26 Connection line 27 Stress cone 28 Low voltage bushing 28 29 Gas chamber 30 Cable 31 Power bushing 32 Insulation Oil 33 ... housing
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 平３−206976（ＪＰ，Ａ) 特開 昭62−172272（ＪＰ，Ａ) 特開 昭61−234371（ＪＰ，Ａ) 特開 昭59−202073（ＪＰ，Ａ) 特開 昭58−92871（ＪＰ，Ａ) (58)調査した分野(Int.Cl.6，ＤＢ名) G01R 31/14 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-206976 (JP, A) JP-A-62-172272 (JP, A) JP-A-61-234371 (JP, A) JP-A-59-1984 202073 (JP, A) JP-A-58-92871 (JP, A) (58) Fields investigated (Int. Cl. 6 , DB name) G01R 31/14
Claims (1)
規電圧を印加する試験用交流トランス（１）と、上記試
験用交流トランス（１）の２次コイル低電圧側と大地間
に設置された交流電流通過用コンデンサ（２）と、上記
交流電流通過用コンデンサ（２）と並列に接続された保
護抵抗（14）（もしくはブロッキングコイル（15））、
直流電圧重畳用電源（５）、及び上記高電圧機器（12）
の絶縁体の劣化に伴って発生するシグナルである直流成
分を測定する直流成分測定装置７とからなり、上記直流
電圧重畳用電源（５）には印加する直流電圧の極性を切
り換えるスイッチ（６）及び当該電源（５）を回路から
電気的に切り離すスイッチ（４）が備えられてなること
を特徴とする絶縁診断装置。1. A test AC transformer (1) for applying an AC normal voltage to a high-voltage device (12) to be measured, and between a secondary coil low-voltage side of the test AC transformer (1) and the ground. An AC current passing capacitor (2) installed in the power supply, a protection resistor (14) (or a blocking coil (15)) connected in parallel with the AC current passing capacitor (2),
DC voltage superimposing power supply (5) and high-voltage equipment (12)
A DC component measuring device 7 for measuring a DC component which is a signal generated due to deterioration of the insulator, and a switch (6) for switching the polarity of the DC voltage applied to the DC voltage superimposing power supply (5). And a switch (4) for electrically disconnecting the power supply (5) from the circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2315594A JP2871075B2 (en) | 1990-11-20 | 1990-11-20 | Insulation diagnostic circuit and device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2315594A JP2871075B2 (en) | 1990-11-20 | 1990-11-20 | Insulation diagnostic circuit and device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04184272A JPH04184272A (en) | 1992-07-01 |
| JP2871075B2 true JP2871075B2 (en) | 1999-03-17 |
Family
ID=18067238
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2315594A Expired - Lifetime JP2871075B2 (en) | 1990-11-20 | 1990-11-20 | Insulation diagnostic circuit and device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2871075B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103257306B (en) * | 2012-10-25 | 2015-06-24 | 国网电力科学研究院武汉南瑞有限责任公司 | Method for diagnosing direct current partial discharging insulation state of converter transformer and measurement system |
| CN104345254A (en) * | 2014-11-21 | 2015-02-11 | 西安伯龙高铁电气有限公司 | Train insulation detection control device |
-
1990
- 1990-11-20 JP JP2315594A patent/JP2871075B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04184272A (en) | 1992-07-01 |
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