JP2586026B2 - Voltage detector - Google Patents
Voltage detectorInfo
- Publication number
- JP2586026B2 JP2586026B2 JP62028931A JP2893187A JP2586026B2 JP 2586026 B2 JP2586026 B2 JP 2586026B2 JP 62028931 A JP62028931 A JP 62028931A JP 2893187 A JP2893187 A JP 2893187A JP 2586026 B2 JP2586026 B2 JP 2586026B2
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- JP
- Japan
- Prior art keywords
- cylindrical ring
- voltage
- contact
- electro
- cylindrical
- 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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Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、開閉機器の導体電圧を測定する電圧検出装
置に関する。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a voltage detector for measuring a conductor voltage of a switchgear.
従来のこの種の電圧検出装置は、第３図に示すよう
に、中心導体31の外周に同軸状に円筒電極32を設け、中
心導体31と円筒電極32との環状空間及び円筒電極32の外
周に絶縁樹脂33を充填して検出ブッシングを形成してい
た。この構造により、中心導体31と円筒電極32との間に
高圧側の静電容量C1を形成し、この容量C1と器外の低圧
側コンデンサC2とにより容量性分圧器を構成して、中心
導体の電圧を測定するようにしていた。As shown in FIG. 3, a conventional voltage detecting device of this type is provided with a cylindrical electrode 32 coaxially around an outer periphery of a central conductor 31, and an annular space between the central conductor 31 and the cylindrical electrode 32 and an outer periphery of the cylindrical electrode 32. Is filled with an insulating resin 33 to form a detection bushing. This structure, the capacitance C 1 of the high-pressure side is formed between the center conductor 31 and the cylindrical electrode 32, constitute a capacitive voltage divider by a low-pressure side capacitor C 2 of the capacitor C 1 and Utsuwagai The voltage of the center conductor was measured.
このような容量性分圧器による電圧測定装置において
は、高圧側及び低圧側の静電容量C1及びC2が一定である
ことが望ましいが、中心導体31と円筒電極32との間に充
填した絶縁樹脂33に、円筒電極32の界面においてクラッ
クが発生し、高圧側の静電容量が変化し、正確な電圧を
測定することができなかった。また、従来においては器
外に低圧側コンデンサを設けなければならないため、設
置スペースを要し、また周囲の温度変化による影響が少
ないように、特性の安定した信頼性の高いものを選択し
て使用しなければならなかった。In the voltage measuring device due to such capacitive voltage divider is the capacitance C 1 and C 2 of the high pressure side and low pressure side is desirably constant, was filled between the central conductor 31 and the cylindrical electrode 32 Cracks occurred in the insulating resin 33 at the interface between the cylindrical electrodes 32, and the capacitance on the high voltage side changed, making it impossible to measure an accurate voltage. In the past, a low-voltage capacitor had to be installed outside the device, which required installation space, and selected and used those with stable characteristics and high reliability so as to be less affected by changes in ambient temperature. I had to.
本発明は、このような従来の問題点に鑑みてなされた
ものであり、絶縁樹脂の劣化や変質による静電容量の変
化を除去して正確な電圧測定を行い、且つ電圧検出装置
の小型化を図ることを目的とする。The present invention has been made in view of such a conventional problem, and removes a change in capacitance due to deterioration or deterioration of an insulating resin, performs accurate voltage measurement, and reduces the size of a voltage detection device. The purpose is to plan.
この目的を達成するため、本発明の電圧検出装置は、
絶縁性ガスを封入した開閉器容器内の可動接触子と固定
接触子との接離部の外周にアーク駆動コイルを配置し、
このアーク駆動コイルの外周に、前記絶縁性ガスを介在
する環状空間を隔てて第１の円筒環を配置し、この第１
の円筒環の外周に絶縁材を介して第２の円筒環を配置
し、前記可動接触子と固定接触子との接離部と第１の円
筒環との間及び該第１の円筒環と第２の円筒環との間に
より容量性分圧器を形成し、前記第１の円筒環及び第２
の円筒環をそれぞれ電気光学結晶素子の透明電極に接続
して電圧センサを形成し、該透明電極間の電圧の大きさ
によって変化する電気光学結晶素子の通過光量の変化に
より、開閉器閉路時の前記可動接触子と固定接触子との
接離部の電圧を検出する電気光学系を設けたことを特徴
とする。In order to achieve this object, the voltage detection device of the present invention comprises:
An arc drive coil is arranged on the outer periphery of the contact / separation part between the movable contact and the fixed contact in the switch container filled with the insulating gas,
A first cylindrical ring is arranged on the outer periphery of the arc driving coil with an annular space interposing the insulating gas therebetween.
A second cylindrical ring is disposed on the outer periphery of the cylindrical ring with an insulating material interposed therebetween, and between the first cylindrical ring and the contact / separation portion between the movable contact and the fixed contact, and between the first cylindrical ring and the first cylindrical ring. Forming a capacitive voltage divider between the first cylindrical ring and the second cylindrical ring;
Each of the cylindrical rings is connected to a transparent electrode of the electro-optic crystal element to form a voltage sensor, and a change in the amount of light passing through the electro-optic crystal element, which varies according to the magnitude of the voltage between the transparent electrodes, causes An electro-optical system for detecting a voltage at a contact / separation portion between the movable contact and the fixed contact is provided.
以下、本発明を第１図及び第２図に示す実施例に基づ
いて具体的に説明する。Hereinafter, the present invention will be specifically described based on the embodiment shown in FIGS.
第１図において、１は開閉容器であり、その両側には
碍子２が取付けられている。一方の碍子２には固定電極
３が固定され、開閉容器１の内部において固定電極３の
先端には固定接触子４が設けられている。他方の碍子２
には、固定接触子４に接離する可動接触子５が取付けら
れており、可動電極（図示せず）上を摺動できるように
構成されている。固定電極３及び可動電極は、引出し電
線６によって外部に配線されている。７は可動接触子５
を環状に囲む導電材よりなる円筒体で、この円筒体７よ
り固定接触子４に向かって突出する導電環８を有し、絶
縁材よりなる支持台９を介して固定電極３に取付けられ
ている。In FIG. 1, reference numeral 1 denotes an opening / closing container, and insulators 2 are attached to both sides thereof. A fixed electrode 3 is fixed to one insulator 2, and a fixed contact 4 is provided at the tip of the fixed electrode 3 inside the openable / closable container 1. The other insulator 2
A movable contact 5 that comes into contact with and separates from the fixed contact 4 is attached to the movable contact 5 so that the movable contact 5 can slide on a movable electrode (not shown). The fixed electrode 3 and the movable electrode are externally wired by a lead wire 6. 7 is a movable contact 5
, Which has a conductive ring 8 protruding from the cylindrical body 7 toward the fixed contact 4, and is attached to the fixed electrode 3 via a support 9 made of an insulating material. I have.
10は円筒体７の外周に巻装したアーク駆動コイルであ
り、一端に円筒体７に、他端は固定電極３にそれぞれ接
続されている。開閉容器１には、SF6等の消弧性ガス11
が封入されている。12は開閉容器１内に取付けられた容
量性分圧器であり、アーク駆動コイル10に環状空間を囲
んで設けた導電材よりなる第１の円筒環13と、この円筒
環13の外周に絶縁材14を介して取付けた導電材よりなる
第２の円筒環15が設けられ、駆動コイル10の表面と第１
の円筒環13との間に高圧側静電容量C1を、また第１の円
筒環13と第２の円筒環15との間に低圧側静電容量C2を形
成するようにしている。なお、第２の円筒環15は図示し
ない導線を介して開閉容器１に設置されている。Reference numeral 10 denotes an arc drive coil wound around the outer periphery of the cylindrical body 7, one end of which is connected to the cylindrical body 7 and the other end of which is connected to the fixed electrode 3, respectively. The opening and closing container 1, arc-extinguishing gas such as SF 6 11
Is enclosed. Reference numeral 12 denotes a capacitive voltage divider mounted in the open / close container 1. A first cylindrical ring 13 made of a conductive material provided around the annular space in the arc driving coil 10, and an insulating material is provided on the outer periphery of the cylindrical ring 13. A second cylindrical ring 15 made of a conductive material is provided, and the second cylindrical ring 15 is
And so as to form a low-pressure side capacitance C 2 between the high-pressure-side capacitance C 1, also a first cylindrical ring 13 and the second cylindrical ring 15 between the cylindrical ring 13 of the. Note that the second cylindrical ring 15 is installed in the openable / closable container 1 via a conductive wire (not shown).
次に、第５図に示す電圧検出システムについて説明す
る。16はパルス発生器でありその出力パルスは電気−光
変換素子17により光パルスに変換され、光ファイバ26を
介して電圧センサ20に与えられる。電圧センサ20は、端
面に透明電極22を有する電気光学結晶素子21,偏光子23,
1/4波長板24及び検光子25より形成されている。透明電
極22,22は、第１図の説明で述べた第１の円筒環13及び
第２の円筒環15と電気的に接続されている。検光子25の
光出力は、光ファイバ27を介して光−電気変換素子18に
伝達され、電気信号に変換されて出力装置19に送られ
る。Next, the voltage detection system shown in FIG. 5 will be described. Reference numeral 16 denotes a pulse generator, the output pulse of which is converted into an optical pulse by an electro-optical conversion element 17 and supplied to a voltage sensor 20 via an optical fiber 26. The voltage sensor 20 includes an electro-optic crystal element 21 having a transparent electrode 22 on an end face, a polarizer 23,
It is formed of a quarter-wave plate 24 and an analyzer 25. The transparent electrodes 22, 22 are electrically connected to the first cylindrical ring 13 and the second cylindrical ring 15 described in the description of FIG. The optical output of the analyzer 25 is transmitted to the optical-electrical conversion element 18 via the optical fiber 27, converted into an electric signal, and sent to the output device 19.
次に、本装置の動作について説明する。閉路操作の指
令が出されると、操作機構（図示せず）によって可動接
触子５は固定電極３の固定接触子４に接触し、開閉機器
が電路を閉路する。これにより、固定電極３に一端を接
続したアーク駆動コイル10に電圧が印加され、このアー
ク駆動コイル10の表面と第１の円筒環13との間に高圧側
静電容量C1が発生する。しかるに、パルス発生器16より
電気パルスを電気−光パルス変換素子17に送信すると、
その信号は電気−光変換素子17で光パルスに変換され
て、光ファイバ26を経て電圧センサ20に送信される。光
パルスは電圧センサーの偏光子23,電気光学結晶素子21,
検光子25を通り、光ファイバ27から光−電気変換素子18
に送信される。光−電気変換素子18は光パルスを電気パ
ルスに変換して出力装置19に出力する。前記電気光学結
晶素子21には、容量性分圧器12の低圧側静電容量C2を形
成する第１の円筒環13及び第２の円筒環15にそれぞれ接
続された透明電極22,22に、静電容量C2側の電圧が印加
されている。この電気光学結晶素子21を通過する光パル
スには開閉機器の閉路状態の正常電圧が作用しており、
開閉機器が正常に運転していることを出力装置19に表示
する。Next, the operation of the present apparatus will be described. When a closing operation command is issued, the movable contact 5 comes into contact with the fixed contact 4 of the fixed electrode 3 by an operating mechanism (not shown), and the switching device closes the electric circuit. As a result, a voltage is applied to the arc drive coil 10 having one end connected to the fixed electrode 3, and a high voltage side capacitance C 1 is generated between the surface of the arc drive coil 10 and the first cylindrical ring 13. However, when an electric pulse is transmitted from the pulse generator 16 to the electro-optical pulse conversion element 17,
The signal is converted into an optical pulse by the electro-optical conversion element 17 and transmitted to the voltage sensor 20 via the optical fiber 26. The light pulse is a voltage sensor polarizer 23, an electro-optic crystal element 21,
After passing through the analyzer 25, the optical fiber 27
Sent to. The light-to-electric conversion element 18 converts the light pulse into an electric pulse and outputs it to the output device 19. The electro-optic crystal element 21 includes transparent electrodes 22 and 22 respectively connected to a first cylindrical ring 13 and a second cylindrical ring 15 forming a low-voltage side capacitance C 2 of the capacitive voltage divider 12. voltage of the capacitance C 2 side is applied. A normal voltage in the closed state of the switching device is applied to the light pulse passing through the electro-optic crystal element 21,
The output device 19 indicates that the switchgear is operating normally.
次に、開路操作の指令により、開閉機器の可動接触子
５が固定接触子４から開離すると、可動接触子５と固定
接触子４との間にアークが発生する。このアークは、固
定接触子４上のアーク足が円筒体７の導電環８に移行
し、円筒体７の外周に巻装されたアーク駆動コイル10に
より導電環８と可動接触子５との間の消弧性ガス11の雰
囲気中を回転しながら消弧して開閉機器は開路する。そ
して、アーク駆動コイル10の印加電圧がなくなり、第１
の円筒環13に誘起された電圧がなくなり、第２の円筒環
15は接地されており、電気光学結晶素子21に作用する透
明電極22,22の電圧がないため、この電気光学結晶素子2
1を通過する光パルスは開閉機器の固定電極側に電圧が
かかっていない状態を出力装置19に表示するものであ
る。Next, when the movable contact 5 of the opening / closing device is separated from the fixed contact 4 by a command of the opening operation, an arc is generated between the movable contact 5 and the fixed contact 4. In this arc, the arc foot on the fixed contact 4 shifts to the conductive ring 8 of the cylindrical body 7, and the arc drive coil 10 wound around the outer circumference of the cylindrical body 7 causes the conductive ring 8 to move between the conductive ring 8 and the movable contact 5. The arc switch extinguishes while rotating in the atmosphere of the arc extinguishing gas 11 to open the switchgear. Then, the voltage applied to the arc drive coil 10 disappears, and the first
The voltage induced in the cylindrical ring 13 of the
15 is grounded, and there is no voltage on the transparent electrodes 22 and 22 acting on the electro-optic crystal element 21.
The light pulse passing through 1 indicates on the output device 19 that no voltage is applied to the fixed electrode side of the switchgear.
本実施例においては、ロータリーアーク方式を採って
おり、SF6ガス中に設置しているので、第１の円筒環13,
第２の円筒環15間のギャップが短くても絶縁強度を高く
とることができる。その結果、コンデンサ容量を大きく
することが可能となる。In the present embodiment, the rotary arc method is adopted, and since the rotary arc method is provided in SF 6 gas, the first cylindrical ring 13,
Even if the gap between the second cylindrical rings 15 is short, the insulation strength can be increased. As a result, it is possible to increase the capacitance of the capacitor.
また、内部に封入したSF6ガスは誘電率が1.002であ
り、空気とほとんど同じであるので、仮に開閉器内に空
気が混入しても、分圧器構成上は支障なく安定に測定す
ることができる。前記第２の円筒環15は０電位となって
いるので、開閉器内壁に凹凸があっても電界集中が起こ
らず、開閉器ケースの設計自由度が増加する。In addition, the SF 6 gas sealed inside has a dielectric constant of 1.002, which is almost the same as air, so that even if air enters the switch, stable measurement can be performed without any problems in the voltage divider configuration. it can. Since the second cylindrical ring 15 is at zero potential, electric field concentration does not occur even if the inner wall of the switch has irregularities, and the degree of freedom in designing the switch case increases.
なお、容量性分圧器の高圧側静電容量を形成するアー
ク駆動コイルの表面を、薄板の導電材よりなる円筒体で
覆ってもよく、固定電極又は可動電極の円周面との間で
形成してもよい。The surface of the arc driving coil forming the high-voltage side capacitance of the capacitive voltage divider may be covered with a thin cylinder made of a conductive material, and may be formed between the fixed electrode and the circumferential surface of the movable electrode. May be.
また、開閉機器，変圧器等の電圧機器とともに、絶縁
ガスを収納，封入した配電盤における電気機器相互を接
続する導電棒に、容量性分圧器を取付けるようにしても
よい。Further, a capacitive voltage divider may be attached to a conductive rod for connecting electric devices in a switchboard containing and enclosing an insulating gas together with voltage devices such as a switchgear and a transformer.
以上に説明したように、本発明においては、開閉容器
内の電極外周面と第１の円筒環の内周面との間に消弧性
ガスを介して高圧側容量を、第１の円筒環の外周面と第
２の円筒環の内周面との間に絶縁材を介した低圧側容量
をそれぞれ形成し、これらの容量によって容量性分圧器
を形成させ、この分圧器の第１の円筒環と第２の円筒環
とに電気光学結晶素子の透明電極に接続して電圧を検出
するようにしている。従来のコンデンサ分圧法ではコン
デンサの温度特性が問題となるが、本発明の場合には開
閉容器内で容量性分圧器を形成しているため、温度の影
響を受けず、安定に測定できる。また、外部にコンデン
サを配置する場合には耐候性を考慮しなければならない
が、本発明では、分圧器、センサ共にガス中に封入され
ているので、外部環境の影響を受けず、安定に使用する
ことができる。このため正確な電圧を検出することがで
き、且つ分圧器の構成が小形となる。As described above, in the present invention, the high pressure side capacity is set between the outer peripheral surface of the electrode in the open / close container and the inner peripheral surface of the first cylindrical ring via the arc-extinguishing gas. A low voltage side capacitor is formed between the outer peripheral surface of the second cylindrical ring and the inner peripheral surface of the second cylindrical ring via an insulating material, and a capacitive voltage divider is formed by these capacitances. A voltage is detected by connecting the ring and the second cylindrical ring to the transparent electrode of the electro-optic crystal element. In the conventional capacitor voltage division method, the temperature characteristics of the capacitor are problematic. However, in the case of the present invention, since the capacitive voltage divider is formed in the open / close container, the measurement can be performed stably without being affected by the temperature. In addition, when arranging a capacitor outside, weather resistance must be considered, but in the present invention, since both the voltage divider and the sensor are sealed in gas, they can be used stably without being affected by the external environment. can do. Therefore, an accurate voltage can be detected, and the configuration of the voltage divider becomes small.
第１図は本発明の実施例を示す一部切欠正面図、第２図
は信号処理のブロック図、第３図は従来の電圧検出器の
例を示す断面図である。 1:開閉容器、2:碍子 3:固定電極、4:固定接触子 5:可動接触子、6:引出し電線 7:円筒体、8:導電環 9:支持台、10:アーク駆動コイル 11:消弧性ガス、12:容量性分圧器 13:第１の円筒環、14:絶縁材 15:第２の円筒環、16:パルス発生器 17:電気−光変換素子、18:光−電気変換素子 19:出力装置、20:電圧センサ 21:電気光学結晶素子、22:透明電極 23:偏光子、24:1/4波長板 25:検光子、26,27:光ファイバFIG. 1 is a partially cutaway front view showing an embodiment of the present invention, FIG. 2 is a block diagram of signal processing, and FIG. 3 is a sectional view showing an example of a conventional voltage detector. 1: Opening / closing container, 2: Insulator 3: Fixed electrode, 4: Fixed contact 5: Movable contact, 6: Lead wire 7: Cylindrical body, 8: Conductive ring 9: Support base, 10: Arc drive coil 11: Turn off Arc gas, 12: capacitive voltage divider 13: first cylindrical ring, 14: insulating material 15: second cylindrical ring, 16: pulse generator 17: electro-optical conversion element, 18: optical-electric conversion element 19: output device, 20: voltage sensor 21: electro-optic crystal element, 22: transparent electrode 23: polarizer, 24: 1/4 wavelength plate 25: analyzer, 26, 27: optical fiber
フロントページの続き (72)発明者 上田 康仁 北九州市八幡西区大字藤田2346番地 株 式会社安川電機製作所内 (56)参考文献 実開 昭60−190107（ＪＰ，Ｕ) 実開 昭48−372（ＪＰ，Ｕ)Continuation of front page (72) Inventor Yasuhito Ueda 2346 Fujita, Yawatanishi-ku, Kitakyushu City Inside Yaskawa Electric Manufacturing Co., Ltd. , U)
Claims (1)
の可動接触子（５）と固定接触子（４）との接離部の外
周にアーク駆動コイル（10）を配置し、このアーク駆動
コイル（10）の外周に、前記絶縁性ガスを介在する環状
空間を隔てて第１の円筒環（13）を配置し、この第１の
円筒環（13）の外周に絶縁材（14）を介して第２の円筒
環（15）を配置し、前記可動接触子（５）と固定接触子
（４）との接離部と第１の円筒環（13）との間及び該第
１の円筒環（13）と第２の円筒環（15）との間により容
量性分圧器（12）を形成し、前記第１の円筒環（13）及
び第２の円筒環（15）をそれぞれ電気光学結晶素子（2
1）の透明電極（22）に接続して電圧センサ（20）を形
成し、該透明電極（22）間の電圧の大きさによって変化
する電気光学結晶素子（21）の通過光量の変化により、
開閉器閉路時の前記可動接触子（５）と固定接触子
（４）との接離部の電圧を検出する電気光学系を設けた
ことを特徴とする電圧検出装置。An arc drive coil (10) is arranged on the outer periphery of a contact / separation portion between a movable contact (5) and a fixed contact (4) in a switch container (1) filled with an insulating gas, A first cylindrical ring (13) is arranged on the outer periphery of the arc driving coil (10) with an annular space interposed between the insulating gases interposed therebetween, and an insulating member (13) is formed on the outer periphery of the first cylindrical ring (13). A second cylindrical ring (15) is disposed through the first cylindrical ring (13), and between the contact / separation portion between the movable contact (5) and the fixed contact (4) and the first cylindrical ring (13). A capacitive voltage divider (12) is formed between the first cylindrical ring (13) and the second cylindrical ring (15), and the first cylindrical ring (13) and the second cylindrical ring (15) are formed. The electro-optic crystal element (2
A voltage sensor (20) is formed by connecting to the transparent electrode (22) of (1), and a change in the amount of light passing through the electro-optic crystal element (21), which changes according to the magnitude of the voltage between the transparent electrodes (22),
A voltage detecting device comprising an electro-optical system for detecting a voltage at a contact / separation portion between the movable contact (5) and the fixed contact (4) when the switch is closed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62028931A JP2586026B2 (en) | 1987-02-09 | 1987-02-09 | Voltage detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62028931A JP2586026B2 (en) | 1987-02-09 | 1987-02-09 | Voltage detector |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS63195576A JPS63195576A (en) | 1988-08-12 |
| JP2586026B2 true JP2586026B2 (en) | 1997-02-26 |
Family
ID=12262144
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62028931A Expired - Lifetime JP2586026B2 (en) | 1987-02-09 | 1987-02-09 | Voltage detector |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2586026B2 (en) |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5256413Y2 (en) * | 1971-05-28 | 1977-12-20 | ||
| JPS60190107U (en) * | 1984-05-23 | 1985-12-17 | 関西電力株式会社 | optical transformation device |
-
1987
- 1987-02-09 JP JP62028931A patent/JP2586026B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPS63195576A (en) | 1988-08-12 |
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