JP3432236B2 - High-speed reclosable grounding device - Google Patents
High-speed reclosable grounding deviceInfo
- Publication number
- JP3432236B2 JP3432236B2 JP20397892A JP20397892A JP3432236B2 JP 3432236 B2 JP3432236 B2 JP 3432236B2 JP 20397892 A JP20397892 A JP 20397892A JP 20397892 A JP20397892 A JP 20397892A JP 3432236 B2 JP3432236 B2 JP 3432236B2
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- speed
- opening
- current
- grounding device
- 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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- Gas-Insulated Switchgears (AREA)
- Emergency Protection Circuit Devices (AREA)
Description
【発明の詳細な説明】
【0001】
【産業上の利用分野】本発明は、電力用高電圧送電線に
おいて、送電線路の碍子連アークホーン間に生じる逆フ
ラッシオーバー(逆閃絡)によって1線地絡事故が発生
した場合、その送電線路を高速で再閉路するために使用
される高速再閉路接地装置に関するもので、特に、前記
地絡事故が発生した相と同一回線の他相にて前記地絡事
故と時差を持って後追い地絡事故が発生した場合でも、
遮断器の再閉路による再送電を可能にする高速再閉路接
地装置に係る。
【0002】
【従来の技術】送電線に雷が落ちると、送電線に吊られ
た碍子連のアークホーンに逆フラッシオーバーが発生す
る。送電線に生じる事故の大半は、この逆フラッシオー
バーを原因とする1線地絡事故である。地絡事故による
故障を解消するためには、故障区間を無電圧として、事
故原因である逆フラッシオーバーを消弧してしまえば良
い。具体的には、故障を起こした送電線の両端にある送
電線路用の遮断器に再閉路動作を行わせることが有効で
ある。再閉路動作とは、一旦開極して、故障区間を無電
圧とし、逆フラッシオーバーを消弧した後、再度投入す
ることである。このような再閉路動作を行うことによ
り、停電に至ることなく、再送電を行うことができる。
再閉路の代表的な方式としては単相再閉路方式がある。
この単相再閉路方式は、電力の変動が少なく、過渡安定
度に優れているため広く使われている。
【0003】ところが、近年では電力需要の増大に伴っ
て、高電圧送電線として1100kVなどのUHV系送
電線が用いられている。このUHV系送電線にて単相再
閉路を行う場合には、従来の500kV系統の場合に比
較して、同一回線の他相や併架された他回線から受ける
静電電磁誘導が大きくなる。このような他相からの静電
電磁誘導が大きいと、碍子連アークホーンの逆フラッシ
オーバーが発生した時、たとえ故障区間両端の遮断器を
開極状態にしたにせよ、逆フラッシオーバーを消弧する
ことが難しくなる。そこで、UHV系のような高電圧送
電線では、逆フラッシオーバーを消弧するために、高電
圧送電線の各相に高速再閉路接地装置が設置されてい
る。すなわち、事故発生箇所をその両端の遮断器によっ
て送電線路から切り離した後、この高速再閉路接地装置
を遮断器の開閉動作と協調して高速投入することによ
り、碍子連アークホーンに持続する電磁誘導電流アーク
を消弧し、且つ即座に開極動作を行って誘導電流を遮断
して、遮断器の再閉路による再送電を可能にしている。
【0004】以下、この高速再閉路接地開閉器を採用し
た保護システムを、図面を参照して具体的に説明する。
図3はこのシステムの構成を示す説明図である。図にお
いて、11はブッシング、13はUHV系の鉄塔であ
る。12は高電圧用の送電線であり、上相、中相、下相
の3線を有し、ブッシング11と鉄塔13の間または鉄
塔13同士の間に張り渡されている。各鉄塔13には、
アークホーン13aを備えた碍子連13bが設けられ、
この碍子連13bによって送電線12が鉄塔13に吊り
下げられている。送電線12の一定区間の両端には、遮
断器(GCB)と高速再閉路接地装置(HSES)が設
けられている。なお、14は雷雲、15は雷である。こ
のシステムにおいて、3線の送電線12のうちの1つに
雷雲14から雷15が落ちると、その送電線12を吊り
下げている碍子連13bのアークホーン13a間に逆フ
ラッシオーバー13cが発生し、送電線12からこの逆
フラッシオーバー13cを介して鉄塔13へ地絡事故電
流が流れ、地絡事故が生じる。
【0005】この逆フラッシオーバー13cにより1線
地絡事故が起きた場合の遮断器(GCB)及び高速再閉
路接地装置(HSES)の動作順序を、図4の動作シー
ケンス図に沿って説明する。すなわち、地絡事故発生前
は、遮断器(GCB)は投入状態、高速再閉路接地装置
(HSES)は開極状態にある。送電線12に地絡事故
が発生すると、送電線保護リレー時間であるT1 時間経
過後、まず遮断器(GCB)が開極動作を行う。しか
し、事故送電線12には、他相からの静電電磁誘導によ
り誘導電流が流れ、それによってアークホーン13a間
には依然として逆フラッシオーバー13cが持続してい
る。そこで、遮断器(GCB)が開極した状態で、高速
再閉路接地装置(HSES)の投入動作を強制的に高速
で行い、アークホーン13a部分で接地されている誘導
電流を高速再閉路接地装置(HSES)側に導くことに
より、アークホーン13aの逆フラッシオーバーを消弧
する。高速再閉路接地装置(HSES)は、θ時間投入
状態を続けて逆フラッシオーバーを消弧した後、開極状
態に戻って誘導電流を遮断し、最後に遮断器(GCB)
が投入動作を行い送電を再開する。
【0006】ところで、図3に示した通り、送電線12
は上相、中相、下相を有しており、各相には所定の負荷
電流が流れているが、このような送電線12の中相にお
いて地絡事故が発生し、図4に示すような動作シーケン
スで再閉路動作を実施するものと仮定すると、送電線1
2の各相に流れる電流は、図5の電流変化図に示すよう
になる。すなわち、図5に示すように、送電線12の中
相においては、地絡事故発生時T01と、遮断器(GC
B)の開極動作開始時T02との間だけ事故電流が流れて
いる。ところが、送電線12の中相は、他の健全相であ
る上相及び下相や併架された他の回線から静電電磁誘導
を受ける。そのため、遮断器(GCB)が開極した状態
では、送電線12の中相のアークホーンには誘導電流に
起因する逆フラッシオーバーが依然として生じているた
め、この逆フラッシオーバーの消弧のために、高速再閉
路接地装置(HSES)を投入する(投入時T03)。す
ると、高速再閉路接地装置には、図5に示すように、そ
の投入時T03以降、最初は直流成分の含まれた地絡事故
電流と電磁誘導電流とが重畳され電流零点よりも変移し
た電流が流れ、その後地絡事故電流が接地されるにつれ
て電磁誘導電流成分が多くなり、電流零点を通る交流電
流が流れることになる。従って、高速再閉路接地装置
(HSES)によってこのような誘導電流を遮断する場
合には、電流零点になるタイミングを捕らえて開極動作
を行う。
【0007】しかしながら、以上のように、逆フラッシ
オーバーを消弧するために、遮断器(GCB)が開極し
た状態で、高速再閉路接地装置(HSES)の投入動作
を行った場合に、高速再閉路接地装置(HSES)に流
れる電磁誘導電流は、図6に示すように、2000Aに
も達する。そして、このような大電流遮断時には、図7
に示すように、電気回路の過渡現象分と故障送電線が他
線から受ける静電誘導電圧が重畳した過渡回復電圧が印
加される。このような比較的大きな電流と、比較的大き
な上昇率、及び高い波高値の過渡回復電圧条件の遮断
は、単にSF6 ガス中で棒状の接触子を開閉するだけの
並切り形の接地装置では遮断することができず、遮断器
と同様にパッファ形の消弧室を有する高速再閉路接地装
置(HSES)が必要となる。
【0008】図8は、前記のような高速再閉路接地装置
(HSES)の一例を示す。この図において、接地タン
ク23内の中心部には、送電線に接続される導体16が
収納され、その一部から分岐する形で固定接触子17が
設けられている。接地タンク23における固定接触子1
7に対向する部分には、可動接触子18が固定接触子1
7と接離可能に設けられている。この可動接触子18
は、その基部において、図示しない操作装置に連結され
ている。また、可動接触子18の先端側の外周には、可
動接触子18と同心円状に消弧ガス案内用のノズル19
が設けられている。このノズル19は、可動接触子18
の外周に可動接触子18と同心円状に配置されたパッフ
ァシリンダ22の先端に固定されている。このパッファ
シリンダ22の基部が可動接触子18の操作装置に連結
され、可動接触子18と共に固定接触子側に向かって往
復動するように構成されている。可動接触子18とパッ
ファシリンダ22との間にパッファ室20が形成されて
おり、その先端側は前記ノズル19に連通している。パ
ッファ室20の基端側(ノズル19と反対側)には、固
定されたパッファピストン21が設けられている。この
パッファピストン21は、可動接触子18及びパッファ
シリンダ22に対してスライド自在に組み込まれてい
る。
【0009】このような構成を有する高速再閉路接地装
置の動作は次の通りである。すなわち、開極動作時に
は、図示しない操作装置を駆動して、可動接触子18及
びパッファシリンダ22を接地タンク23側(図中下
方)に移動させ、固定接触子17と可動接触子18とを
開離させる。すると、移動するパッファシリンダ22と
固定されているパッファピストン21との間のパッファ
室20の容積が縮小し、パッファ室20内部の絶縁ガス
が消弧ガス24となってノズル19から吹き出され、固
定接触子17と可動接触子18との間のアークを消弧す
る。この場合の可動接触子18のストロークとパッファ
室20のパッファ圧力ΔPとの関係は、図9に示す通り
である。すなわち、可動接触子18の開極ストローク2
5のほぼ1/2の行程においてパッファ圧力は最大値に
達し、開極完了に伴ない圧力は低下している。
【0010】
【発明が解決しようとする課題】ところで、前記のよう
に、送電線の一相で地絡事故が発生して高速再閉路接地
装置によって電流遮断を行う場合、さらに、送電線の隣
接する他の相で直流電流成分の多い後追い故障が発生す
ると、先行の地絡事故発生相の高速再閉路接地装置に零
ミス電流が流れるという問題を生じる。すなわち、例え
ば、図5に示すように、送電線の中相で地絡事故が発生
し、この中相に隣接する上相で、時差を持って時刻T04
において地絡事故(後追い故障)が発生し、この後追い
故障事故のタイミングが、中相の高速再閉路接地装置
(HSES)の開極タイミングと重なると共に、後追い
故障事故電流に直流電流成分が多い場合には、中相の送
電線には、上相の事故電流による電磁誘導で生じた直流
電流成分の多い誘導電流が流れ、図5のA部に示すよう
に、中相の高速再閉路接地装置(HSES)には、数サ
イクルの間、電流零点を形成しない零ミス電流が流れる
ことになる。この零ミス電流を遮断することは、通常の
交流電流の零点遮断に比較すると格段に困難であり、従
来の高速再閉路接地装置の能力を越えたものである。そ
の結果、後追い故障の発生タイミングがちょうど中相の
高速再閉路接地装置の開極タイミングと重なり、合わせ
て後追い故障電流分に直流電流分が多く含まれている場
合には、再閉路が実現されず、高電圧の電力送電が停止
するという重大な問題が発生することになる。
【0011】この点を、図8の高速再閉路接地装置の動
作に従って具体的に述べると、次のようになる。まず、
図8の装置では、可動接触子18が開極動作を停止する
までの間、パッファシリンダ22内の絶縁性消弧ガスを
固定側と可動側の両接触子17,18間に発生している
アークに吹き付けることにより、アークの消弧と電流遮
断及び電流遮断後の耐極間電圧責務を処理している。と
ころが、前記高速再閉路接地装置に求められる開極時の
過渡回復電圧性能を考えると、図7の波形に示すよう
に、商用周波の1/2のサイクルで過渡回復電圧ピーク
を迎えるため、開極スピードは遮断器並の速度が必要と
なり、図9に示すような開極開始時からストロークエン
ドに達するまでの時間tが短くなり、ΔPが一定値以上
にある実質のガス流の吹き付け時間は、2サイクル程度
が限界である。
【0012】一方、高速再閉路接地装置開極動作直後
で、まだ高速再閉路接地装置が電流遮断を完了する前に
前述のように隣接相で後追い故障が発生すると、図5の
A部に示すような電流零点を形成しない誘導電流(約数
千A)が4サイクル程度流れる条件が発生する。この場
合、交流電流の消弧メカニズム上、電流零点を形成しな
いアークの消弧が難しいことから、このタイミングで後
追い故障誘導電流を受けた高速再閉路接地装置はストロ
ーク終端まで開極動作を終了しても極間にアークを形成
し続けることになる。そして、その後、電流零点が復帰
したアーク電流となっても2サイクル程度であるパッフ
ァ室からのガス流の吹き付け時間はすでに経過している
ため、消弧不能状態のままとなる。
【0013】本発明は以上のような従来技術の有する問
題点を解消するために提案されたものであり、その目的
は、1線地絡事故発生後に他相で後追い地絡事故が発生
し、それが先行の地絡事故発生相の接地装置の開極途中
であっても、先行の地絡事故発生相における誘導電流の
遮断を確実に行うことができ、その後の遮断器の高速再
閉路を可能とした高速再閉路接地装置を提供することで
ある。
【0014】
【課題を解決するための手段】本発明による高速再閉路
接地装置は、遮断器を結ぶ高電圧送電線の各相に設置さ
れ、主接点と接地回路とを備えており、前記送電線に設
けられた碍子連のアークホーンにおける逆フラッシオー
バーによる1線地絡事故に対して、前記送電線の両端に
ある遮断器を開極した状態で高速で投入動作を行い、前
記逆フラッシオーバーの消弧後に開極動作を行う高速再
閉路接地装置において、前記主接点には第2開極接点が
電気的に直列に接続され、この第2開極接点には、前記
接地回路に直接接続される第2主接触子と、前記第2開
極接点の開極動作の際にこの接点間に発生する極間アー
クを転流する転流接触子部、及びこの転流接触子部に接
続される抵抗体が配置され、前記第2開極接点が、前記
主接点の開極に合わせて開極するように構成されたこと
を特徴としている。
【0015】
【作用】以上のように構成された本発明の作用は次の通
りである。すなわち、地絡事故が発生し、地絡事故発生
相の遮断器を開極した状態で地絡事故発生相の高速再閉
路接地装置を高速で投入動作させてアークホーンにおけ
る逆フラッシオーバーを消弧した後、地絡事故発生相の
高速再閉路接地装置に開極指令を出した時点から、一定
の時差を持って、静電電磁誘導の影響が大きい同一回線
の他相にて後追い地絡事故が発生し、先行地絡事故発生
相に電流零点を形成しない直流電流成分の多い電流が流
れた場合には、先行地絡事故発生相の高速再閉路接地装
置の主接点の開極に合わせて第2開極接点を開極させる
ことで、接点間に発生する極間アークを転流接触子部に
移動させ、前記電流零点を形成しない直流電流成分の多
い電流を抵抗通電することによって、直流電流成分を減
衰させて電流零点を復帰させることができる。この結
果、主接点において、地絡事故発生相の誘導電流を容易
に遮断することが可能となる。
【0016】
【実施例】以下には、本発明による高速再閉路接地装置
の一実施例を、図1及び図2を参照して具体的に説明す
る。
【0017】まず、図1は、本発明による高速再閉路接
地装置の一実施例を示す構成図である。すなわち、図1
に示すように、接地タンク23内に収納され、送電線に
接続される導体16の下方には、高速再閉路接地装置の
主接点1と第2開極接点2が上下に配置され、電気的に
直列に接続されている。この場合、第2開極接点2は、
接地側に配置され、直接接地回路に接続される第2主接
触子3と、開極動作の際に接点間に発生する極間アーク
を転流する転流接触子部4を備えている。さらに、転流
接触子部4は、第2主接触子3の先端部の周囲に、第2
主接触子3の先端部の表面をある程度の間隔を開けて覆
うようにして配置された転流接触子5と、第2主接触子
3の周囲に配置され、転流接触子5に接続された抵抗体
6を備えている。
【0018】また、図中7は、主接点1及び第2開極接
点2の可動部を駆動する操作機構、8は主接点1及び第
2開極接点2の可動側を電気的・機械的に接続するセン
ターピースである。より詳細には、第2開極接点2に
は、第2主接触子3と対向するように第2可動接触子9
が配置されており、操作機構7によって駆動され、第2
主接触子3及び転流接触子5と接離するように構成され
ている。そしてまた、前記のような第2開極接点2の全
体は、絶縁筒10によって覆われており、この絶縁筒1
0は、センターピース8の支持部材を兼ねている。な
お、主接点1の詳細な構成は、図8に示した従来例と基
本的に同様であるため、ここでは説明を省略する。
【0019】以上のような構成を有する本実施例の作用
は次の通りである。すなわち、図3に示すように、ある
相で1線地絡事故が発生すると、その相の送電線12で
は、遮断器(GCB)が開極し、電流を遮断する。その
後、一定のタイミングで、本実施例の高速再閉路接地装
置(HSES)を投入し、アークホーン13a間の逆フ
ラッシオーバー13cを消弧する。投入された高速再閉
路接地装置(HSES)に対して、一定の時間θ経過後
に開極指令を送る。この開極指令によって、操作機構7
を起動し、主接点1の開極動作を行う。それと同時に、
操作機構7によって第2開極接点2の第2可動接触子9
を動作させ、第2開極接点2を開極させる。この第2開
極接点2の開極動作に伴ない、接点間に発生した極間ア
ークが転流接触子5に移動し、電流零点を形成しない直
流電流成分の多い電流が抵抗体6に通電し、直流電流成
分が直ちに減衰される。この結果、電流零点が復帰し
て、主接点1における電流遮断が可能になる。また、こ
の状態で、特に他相で後追い地絡事故が発生しなけれ
ば、高速再閉路接地装置の開極は成功し、誘導電流の遮
断が行われ、引き続いて遮断器(GCB)が投入されて
送電線の再閉路がなされる。
【0020】ところで、一般に、アークホーン13a間
の逆フラッシオーバー13cを消弧するには、アークホ
ーン間電圧と同等の電圧が得られなければ、消弧可能と
はならない。この場合、アークホーン間電圧は、気象・
設置条件などにより異なるが、1000kV送電線の場
合、おおむね4〜8kV以下でなくては、消弧可能とは
いえない。例えば、高速再閉路設置装置(HSES)投
入時の高速再閉路接地装置(HSES)の通電電流が2
000A程度である場合には、抵抗体6の抵抗値は、2
〜4Ω以下でなくては、逆フラッシオーバー13cを消
弧することはできない。しかしながら、図2の特性図に
示すように、2〜4Ωの抵抗値では、1/2サイクル以
内で電流零点を復帰させることは不可能であり、最低5
〜10Ω程度の抵抗値が必要となる。これに対して、本
実施例においては、抵抗体6への通電を、主接点1の開
極動作時のみ行い、投入時には、第2主接触子3を介し
て直接接地可能であるため、逆フラッシオーバー13c
の消弧が可能になっている。
【0021】また、高速再閉路接地装置(HSES)投
入時間である約800msの間、絶えず抵抗体に200
0Aの電流を流した場合には、10Ωの抵抗体ではその
消費エネルギーは約10MJであるが、本実施例におい
ては、抵抗体への通電時間は、開極動作時の約10ms
程度であり、10Ωの抵抗体の消費エネルギーは100
kJ程度となり、抵抗体の設計が有利になる利点もあ
る。
【0022】なお、本発明は、前記実施例に限定される
ものではなく、例えば、主接点、第2開極接点、及び操
作機構などの具体的な構成は適宜選択可能であり、第2
開極接点の細部の構成も適宜選択可能である。
【0023】
【発明の効果】以上述べたように、本発明においては、
主接点に第2開極接点を電気的に直列に接続し、この第
2開極接点には、第2主接触子と転流接触子部及び抵抗
体を配置することにより、1線地絡事故発生後に他相で
後追い地絡事故が発生し、それが先行の地絡事故発生相
の接地装置の開極途中であっても、主接点の開極に合わ
せて第2開極接点を開極させることで、電流零点を形成
しない直流電流成分の多い電流を抵抗通電し、直流電流
成分を減衰させて電流零点を復帰させることができるた
め、先行の地絡事故発生相における誘導電流の遮断を確
実に行うことができ、その後の遮断器の高速再閉路を可
能とした高速再閉路接地装置を提供することができる。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-voltage power transmission line, in which a single line is formed by a reverse flashover generated between arc horns on a power transmission line. The present invention relates to a high-speed reclosable grounding device used to reclose a transmission line at a high speed when a ground fault occurs, particularly, in the other phase of the same line as the phase in which the ground fault occurred. Even if a trailing ground fault occurs with a time difference from the ground fault,
The present invention relates to a high-speed reclosable grounding device capable of retransmitting power by reclosing a circuit breaker. 2. Description of the Related Art When lightning strikes a transmission line, a reverse flashover occurs in an arc horn of a series of insulators suspended on the transmission line. Most of the accidents that occur in transmission lines are single-line ground faults caused by this reverse flashover. In order to eliminate the fault due to the ground fault, it is only necessary to set the fault section to no voltage and extinguish the reverse flashover which is the cause of the fault. Specifically, it is effective to cause the circuit breakers for the transmission line at both ends of the failed transmission line to perform the reclosing operation. The reclosing operation is to open the pole once, set the fault section to no voltage, extinguish the reverse flashover, and then turn it on again. By performing such a reclosing operation, power transmission can be performed again without a power failure.
As a typical method of reclosing, there is a single-phase reclosing method.
This single-phase reclosing method is widely used because of its small power fluctuation and excellent transient stability. However, in recent years, as power demand has increased, UHV transmission lines such as 1100 kV have been used as high-voltage transmission lines. When a single-phase reclosing is performed on this UHV transmission line, electrostatic electromagnetic induction received from another phase of the same line or another line that is paralleled becomes larger than in the case of the conventional 500 kV system. If such electromagnetic induction from other phases is large, the reverse flashover is extinguished when a reverse flashover of the arc horn occurs, even if the circuit breakers at both ends of the fault section are opened. It becomes difficult to do. Therefore, in a high-voltage transmission line such as a UHV system, a high-speed reclosing grounding device is installed in each phase of the high-voltage transmission line to extinguish the reverse flashover. In other words, after the location where the accident occurred is cut off from the transmission line by the circuit breakers at both ends, this high-speed reclosing grounding device is turned on at high speed in coordination with the opening and closing operation of the circuit breaker, so that the electromagnetic induction sustained by the insulator-connected arc horn can be maintained. The current arc is extinguished, and the opening operation is immediately performed to cut off the induced current, thereby enabling the power transmission by re-closing the circuit breaker. [0004] A protection system employing the high-speed reclosable grounding switch will be specifically described below with reference to the drawings.
FIG. 3 is an explanatory diagram showing the configuration of this system. In the figure, 11 is a bushing and 13 is a UHV-type steel tower. Reference numeral 12 denotes a high-voltage transmission line, which has three lines of an upper phase, a middle phase, and a lower phase, and is stretched between the bushing 11 and the tower 13 or between the towers 13. Each tower 13 has
An insulator series 13b having an arc horn 13a is provided,
The transmission line 12 is suspended from the tower 13 by the insulator string 13b. At both ends of a fixed section of the transmission line 12, a circuit breaker (GCB) and a high-speed reclosable grounding device (HSES) are provided. In addition, 14 is a thundercloud and 15 is lightning. In this system, when lightning 15 falls from a thundercloud 14 on one of the three transmission lines 12, a reverse flashover 13c occurs between the arc horns 13a of the insulator string 13b suspending the transmission line 12. Then, a ground fault current flows from the transmission line 12 to the steel tower 13 through the reverse flashover 13c, and a ground fault occurs. [0005] The operation sequence of the circuit breaker (GCB) and the high-speed reclosing grounding device (HSES) when a one-line ground fault occurs due to the reverse flashover 13c will be described with reference to the operation sequence diagram of FIG. That is, before the occurrence of the ground fault, the circuit breaker (GCB) is in the closed state, and the high-speed reclosable grounding device (HSES) is in the open state. When a ground fault in the transmission line 12 occurs, after time T 1 elapses is power transmission line protection relay time, first circuit breaker (GCB) performs opening operation. However, an induced current flows through the accident transmission line 12 due to electrostatic electromagnetic induction from another phase, whereby the reverse flashover 13c is still maintained between the arc horns 13a. Therefore, with the circuit breaker (GCB) opened, the closing operation of the high-speed reclosable grounding device (HSES) is forcibly performed at a high speed, and the induction current grounded at the arc horn 13a is reduced by the high-speed reclosable grounding device. By guiding to the (HSES) side, the reverse flashover of the arc horn 13a is extinguished. The high-speed reclosable grounding device (HSES) continues to be turned on for θ hours, extinguishes the reverse flashover, returns to the open state, cuts off the induced current, and finally turns off the circuit breaker (GCB).
Performs a power-on operation and restarts power transmission. By the way, as shown in FIG.
Has an upper phase, a middle phase, and a lower phase, and a predetermined load current flows in each phase. However, a ground fault occurs in the middle phase of the power transmission line 12 as shown in FIG. Assuming that the reclosing operation is performed in such an operation sequence, the transmission line 1
The current flowing in each phase of No. 2 is as shown in the current change diagram of FIG. That is, as shown in FIG. 5, in the middle phase of the transmission line 12, a ground fault occurrence time T 01, the circuit breaker (GC
Fault current flows only during the opening operation start T 02 of B). However, the middle phase of the transmission line 12 receives electrostatic and electromagnetic induction from other sound phases, that is, the upper phase and the lower phase, and other lines that are bridged. Therefore, in a state where the circuit breaker (GCB) is opened, a reverse flashover caused by the induced current still occurs in the middle-phase arc horn of the transmission line 12, and the arc of the reverse flashover is extinguished. , to introduce high-speed reclosing ground device (HSES) (turned on at the time T 03). Then, the high-speed reclosing grounding device, as shown in FIG. 5, the - on T 03 later, was initially displaced than the included ground fault current and the electromagnetic induction current and is superimposed current zero point of the direct current component As the current flows, as the ground fault current is grounded, the electromagnetic induction current component increases, and an alternating current passing through the current zero point flows. Therefore, when such an induced current is cut off by the high-speed reclosing grounding device (HSES), the opening operation is performed by capturing the timing at which the current becomes zero. However, as described above, in order to extinguish the reverse flashover, when the closing operation of the high-speed reclosable grounding device (HSES) is performed with the circuit breaker (GCB) opened, The electromagnetic induction current flowing through the reclosing grounding device (HSES) reaches 2000 A as shown in FIG. At the time of such a large current interruption, FIG.
As shown in (2), a transient recovery voltage is applied in which a transient phenomenon of the electric circuit and an electrostatic induction voltage received by the failed transmission line from another line are superimposed. Such a relatively large current, a relatively large rate of rise, and interruption of the transient recovery voltage condition with a high peak value can be achieved by a side-by-side grounding device that merely opens and closes a rod-shaped contact in SF 6 gas. A high-speed reclosable grounding device (HSES), which cannot be interrupted and has a puffer-type arc-extinguishing chamber like a circuit breaker, is required. FIG. 8 shows an example of a high-speed reclosable grounding device (HSES) as described above. In this figure, a conductor 16 connected to a power transmission line is accommodated in a central portion in the grounding tank 23, and a fixed contact 17 is provided so as to branch off from a part thereof. Fixed contact 1 in ground tank 23
The movable contact 18 is fixed to the fixed contact 1
7 is provided so as to be able to come and go. This movable contact 18
Is connected at its base to an operating device (not shown). A nozzle 19 for guiding the arc-extinguishing gas is provided concentrically with the movable contact 18 on the outer periphery on the tip side of the movable contact 18.
Is provided. The nozzle 19 is provided with a movable contact 18
Is fixed to the tip of a puffer cylinder 22 which is arranged concentrically with the movable contact 18 on the outer periphery of. The base of the puffer cylinder 22 is connected to the operating device of the movable contact 18 and is configured to reciprocate with the movable contact 18 toward the fixed contact. A puffer chamber 20 is formed between the movable contact 18 and the puffer cylinder 22, and the tip side thereof communicates with the nozzle 19. A fixed puffer piston 21 is provided on the base end side (the side opposite to the nozzle 19) of the puffer chamber 20. The puffer piston 21 is slidably assembled with the movable contact 18 and the puffer cylinder 22. The operation of the high-speed reclosable grounding apparatus having such a configuration is as follows. That is, at the time of the opening operation, an operating device (not shown) is driven to move the movable contact 18 and the puffer cylinder 22 toward the ground tank 23 (downward in the figure), and the fixed contact 17 and the movable contact 18 are opened. Let go. Then, the volume of the puffer chamber 20 between the moving puffer cylinder 22 and the fixed puffer piston 21 is reduced, and the insulating gas inside the puffer chamber 20 becomes the arc-extinguishing gas 24 and is blown out from the nozzle 19 to be fixed. The arc between the contact 17 and the movable contact 18 is extinguished. The relationship between the stroke of the movable contact 18 and the puffer pressure ΔP in the puffer chamber 20 in this case is as shown in FIG. That is, the opening stroke 2 of the movable contact 18
In almost half the stroke of 5, the puffer pressure reaches the maximum value, and the pressure decreases with the completion of the opening. As described above, when a ground fault occurs in one phase of a transmission line and current is interrupted by a high-speed reclosing grounding device, as described above, furthermore, the adjacent line of the transmission line When a follow-up failure having a large DC current component occurs in another phase, a problem arises in that a zero-miss current flows through the high-speed reclosable grounding device in the preceding ground fault accident occurrence phase. That is, for example, as shown in FIG. 5, a ground fault occurs in the middle phase of the transmission line, and the upper phase adjacent to the middle phase has a time difference of time T 04.
In this case, a ground fault (back-up fault) occurs at the same time, the timing of the back-up fault overlaps with the opening timing of the medium-phase high-speed reclosable grounding device (HSES), and the follow-up fault fault current has a large DC current component. In the medium-phase transmission line, an induced current having a large DC current component generated by electromagnetic induction due to the upper-phase fault current flows, and as shown in part A of FIG. In (HSES), a zero-miss current that does not form a current zero point flows for several cycles. It is much more difficult to cut off this zero-miss current than to cut off the zero point of ordinary alternating current, and it exceeds the capability of the conventional high-speed reclosable grounding device. As a result, when the follow-up failure occurs exactly at the same timing as the opening timing of the middle-phase high-speed reclosing grounding device, and when the follow-up failure current includes a large amount of DC current, reclosing is realized. Therefore, a serious problem that high-voltage power transmission stops is generated. [0011] This point will be specifically described below according to the operation of the high-speed reclosable grounding device of FIG. First,
8, the insulating arc-extinguishing gas in the puffer cylinder 22 is generated between the fixed-side and movable-side contacts 17 and 18 until the movable contact 18 stops the opening operation. By spraying the arc, the arc is extinguished, the current is interrupted, and the inter-electrode voltage duty after the current is interrupted is processed. However, considering the transient recovery voltage performance at the time of opening required for the high-speed reclosable grounding device, as shown in the waveform of FIG. 7, the transient recovery voltage peaks at a half cycle of the commercial frequency. The pole speed requires a speed equivalent to that of a circuit breaker, and the time t from the start of opening to the end of stroke as shown in FIG. 9 is shortened. The limit is about two cycles. On the other hand, if a follow-up failure occurs in the adjacent phase as described above immediately after the opening operation of the high-speed reclosable grounding device and before the high-speed reclosable grounding device completes the current interruption, as shown in part A of FIG. A condition occurs in which an induced current (about several thousand A) that does not form a current zero point flows for about four cycles. In this case, the arc extinguishing mechanism of the alternating current makes it difficult to extinguish an arc that does not form a current zero point.Therefore, the high-speed reclosable grounding device that has received the follow-up failure induced current at this timing ends the opening operation until the end of the stroke. Even so, an arc is continuously formed between the poles. After that, even if the arc current has returned to the current zero point, the arc-extinguishing time, which is about two cycles, has already passed since the gas flow from the puffer chamber has already passed, and the arc-extinguishing state remains. The present invention has been proposed to solve the above-mentioned problems of the prior art. It is an object of the present invention to provide a method in which after a single-line ground fault occurs, a trailing ground fault occurs in another phase. Even if it is during the opening of the grounding device of the preceding ground fault accident phase, the induced current in the preceding ground fault accident phase can be reliably shut off, and the high-speed reclosing of the circuit breaker after that can be performed. It is an object of the present invention to provide a high-speed reclosable grounding device. A high-speed reclosable grounding device according to the present invention is provided in each phase of a high-voltage transmission line connecting a circuit breaker, and has a main contact and a grounding circuit. In response to a single-line ground fault due to reverse flashover in an arc horn of an insulator series provided on an electric wire, a closing operation is performed at a high speed with circuit breakers at both ends of the transmission line being opened, and the reverse flashover is performed. In the high-speed reclosable grounding device that performs the opening operation after the arc is extinguished, a second opening contact is electrically connected in series to the main contact, and the second opening contact is directly connected to the grounding circuit. a second main contact is, the second opening
Pole commutation contact unit for commutation poles between arc generated between the contacts upon opening operation of the contacts, and the resistor connected to the commutation contact terminal part is disposed, said second opening The contact is configured to be opened in accordance with the opening of the main contact. The operation of the present invention configured as described above is as follows. In other words, a ground fault occurs and the high-speed reclosing grounding device of the ground fault phase is turned on at high speed with the circuit breaker of the ground fault phase open to extinguish the reverse flashover in the arc horn. From the point when the opening command was issued to the high-speed reclosable grounding device in the phase where the ground fault occurred Occurs, and a current having a large DC current component that does not form a current zero point flows in the preceding ground fault occurrence phase, in accordance with the opening of the main contact of the high-speed reclosable grounding device of the preceding ground fault occurrence phase. By opening the second opening contact, the arc between the contacts generated between the contacts is moved to the commutation contact portion, and a current having a large DC current component that does not form the current zero point is flowed by resistance, so that the DC current is reduced. Attenuate the current component to return the current zero point It is possible. As a result, it is possible to easily cut off the induced current in the ground fault occurrence phase at the main contact. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the high-speed reclosing and grounding apparatus according to the present invention will be specifically described below with reference to FIGS. FIG. 1 is a block diagram showing an embodiment of a high-speed reclosing grounding device according to the present invention. That is, FIG.
As shown in the figure, below the conductor 16 housed in the grounding tank 23 and connected to the transmission line, the main contact 1 and the second opening contact 2 of the high-speed reclosable grounding device are vertically arranged, Are connected in series. In this case, the second opening contact 2 is
A second main contact 3 disposed on the ground side and directly connected to a ground circuit, and a commutation contact 4 for commutating an arc between the poles generated between the contacts during the opening operation. Further, the commutation contact part 4 is provided around the tip of the second main contact
The commutation contact 5 is disposed so as to cover the surface of the tip of the main contact 3 at a certain interval, and is disposed around the second main contact 3 and connected to the commutation contact 5. The resistor 6 is provided. In the figure, reference numeral 7 denotes an operating mechanism for driving the movable portions of the main contact 1 and the second opening contact 2, and 8 denotes an electric / mechanical operation of the movable side of the main contact 1 and the second opening contact 2. A centerpiece connected to More specifically, the second movable contact 9 is attached to the second opening contact 2 so as to face the second main contact 3.
Are driven by the operating mechanism 7 and the second
The main contact 3 and the commutation contact 5 are configured to be in contact with and separated from each other. Further, the whole of the second opening contact 2 as described above is covered with an insulating cylinder 10.
Reference numeral 0 also serves as a support member for the center piece 8. Note that the detailed configuration of the main contact 1 is basically the same as the conventional example shown in FIG. The operation of this embodiment having the above configuration is as follows. That is, as shown in FIG. 3, when a one-line ground fault occurs in a certain phase, the circuit breaker (GCB) is opened in the transmission line 12 in that phase to cut off the current. Thereafter, at a certain timing, the high-speed reclosing grounding device (HSES) of this embodiment is turned on to extinguish the reverse flashover 13c between the arc horns 13a. An opening command is sent to the input high-speed reclosing grounding device (HSES) after a lapse of a predetermined time θ. By this opening command, the operating mechanism 7
Is activated to open the main contact 1. At the same time,
The second movable contact 9 of the second opening contact 2 is operated by the operating mechanism 7.
Is operated to open the second opening contact 2. With the opening operation of the second opening contact 2, the arc generated between the contacts moves to the commutation contact 5, and a current having a large DC current component that does not form a current zero point flows through the resistor 6. Then, the DC current component is immediately attenuated. As a result, the current zero is restored, and the current at the main contact 1 can be interrupted. Also, in this state, if a back-to-back ground fault does not occur, especially in another phase, the opening of the high-speed reclosing grounding device is successful, the induction current is cut off, and the circuit breaker (GCB) is subsequently turned on. The transmission line is reclosed. Generally, in order to extinguish the reverse flashover 13c between the arc horns 13a, the arc cannot be extinguished unless a voltage equivalent to the voltage between the arc horns is obtained. In this case, the voltage between the arc horns
Although it depends on the installation conditions and the like, in the case of a 1000 kV transmission line, the arc cannot be extinguished unless it is approximately 4 to 8 kV or less. For example, when the high-speed reclosable grounding device (HSES) is turned on when the high-speed reclosable grounding device (HSES) is turned on, the current is 2
000 A, the resistance value of the resistor 6 is 2
If it is not more than 4Ω, the reverse flashover 13c cannot be extinguished. However, as shown in the characteristic diagram of FIG. 2, with a resistance value of 2 to 4Ω, it is impossible to return the current zero point within サ イ ク ル cycle.
A resistance of about 10 to 10Ω is required. On the other hand, in the present embodiment, the resistor 6 is energized only during the opening operation of the main contact 1 and can be directly grounded via the second main contact 3 at the time of closing. Flashover 13c
Can be extinguished. The resistance is constantly applied to the resistor for about 800 ms, which is the closing time of the high speed reclosable grounding device (HSES).
When a current of 0 A flows, the energy consumption of a 10Ω resistor is about 10 MJ, but in this embodiment, the energizing time to the resistor is about 10 ms during the opening operation.
And the energy consumption of a 10Ω resistor is 100
This is about kJ, and there is also an advantage that the design of the resistor is advantageous. The present invention is not limited to the above-described embodiment. For example, specific configurations such as a main contact, a second opening contact, and an operation mechanism can be appropriately selected.
The detailed configuration of the opening contact can also be appropriately selected. As described above, in the present invention,
A second open contact is electrically connected in series to the main contact, and a second main contact, a commutation contact portion, and a resistor are arranged on the second open contact, thereby forming a one-line ground fault. After the accident, a back-to-back ground fault occurs in another phase, and even if it is in the process of opening the grounding device in the preceding ground fault accident phase, the second opening contact is opened in accordance with the opening of the main contact. By setting the pole, a current with a large DC current component that does not form a current zero point can be conducted by resistance, and the DC current component can be attenuated to restore the current zero point. Can be performed reliably, and a high-speed reclosable grounding device that enables high-speed reclosing of the circuit breaker thereafter can be provided.
【図面の簡単な説明】
【図1】本発明による高速再閉路接地装置の一実施例を
示す構成図。
【図2】図1の抵抗体の抵抗値と電流零点の復帰時点と
の関係を示す特性図。
【図3】高速再閉路接地装置の一例を示すシステム構成
図。
【図4】高速再閉路接地装置の動作シーケンス図。
【図5】高速再閉路接地装置と各相に流れる電流の変化
を示す特性図。
【図6】高速再閉路接地装置の動作相への他相からの静
電誘導電流及び電磁誘導電流の特性を示す波形図。
【図7】高速再閉路接地装置の開極時の過渡回復電圧波
形図。
【図8】従来の高速再閉路接地装置における電極部分の
開極状態を示す断面図。
【図9】図8の高速再閉路接地装置におけるパッファ室
圧力と動作ストロークの関係を示す特性図。
【符号の説明】
1…主接点
2…第2開極接点
3…第2主接触子
4…転流接触子部
5…転流接触子
6…抵抗体
7…操作機構
8…センターピース
9…第2可動接触子
10…絶縁筒
11…ブッシング
12…送電線
13…鉄塔
13a…アークホーン
13b…碍子連
13c…逆フラッシオーバー
16…導体
17…固定接触子
18…可動接触子
19…ノズル
20…パッファ室
21…パッファピストン
22…パッファシリンダ
23…接地タンク
24…消弧ガスBRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a configuration diagram showing one embodiment of a high-speed reclosable grounding device according to the present invention. FIG. 2 is a characteristic diagram showing a relationship between a resistance value of the resistor in FIG. 1 and a time point at which a current zero point returns. FIG. 3 is a system configuration diagram showing an example of a high-speed reclosing ground device. FIG. 4 is an operation sequence diagram of the high speed reclosable grounding device. FIG. 5 is a characteristic diagram showing a change in a current flowing in each phase of the high-speed reclosable grounding device. FIG. 6 is a waveform diagram showing characteristics of an electrostatic induction current and an electromagnetic induction current from another phase to an operation phase of the high-speed reclosable grounding device. FIG. 7 is a transient recovery voltage waveform diagram when the high-speed reclosable grounding device is opened. FIG. 8 is a sectional view showing an open state of an electrode portion in the conventional high-speed reclosable grounding device. FIG. 9 is a characteristic diagram showing a relationship between a puffer chamber pressure and an operation stroke in the high-speed reclosing-grounding device of FIG. 8; [Description of Signs] 1 ... Main contact 2 ... Second opening contact 3 ... Second main contact 4 ... Commuting contact part 5 ... Commuting contact 6 ... Resistor 7 ... Operation mechanism 8 ... Center piece 9 ... 2nd movable contact 10 ... insulating cylinder 11 ... bushing 12 ... transmission line 13 ... steel tower 13a ... arc horn 13b ... insulator string 13c ... reverse flashover 16 ... conductor 17 ... fixed contact 18 ... movable contact 19 ... nozzle 20 ... Puffer chamber 21 Puffer piston 22 Puffer cylinder 23 Ground tank 24 Arc extinguishing gas
───────────────────────────────────────────────────── フロントページの続き (72)発明者 野田 英樹 東京都港区芝浦1丁目1番1号 株式会 社東芝 本社事務所内 (56)参考文献 特開 平5−199653(JP,A) 特開 昭55−92530(JP,A) 実開 昭60−183517(JP,U) 実開 昭56−110707(JP,U) (58)調査した分野(Int.Cl.7,DB名) H01H 33/70 - 33/99 H02B 13/02,13/075 H02H 1/00 - 3/07 ──────────────────────────────────────────────────続 き Continuation of front page (72) Inventor Hideki Noda 1-1-1, Shibaura, Minato-ku, Tokyo Inside the head office of Toshiba Corporation (56) References JP-A-5-199653 (JP, A) Showa 55-92530 (JP, A) Actually open Showa 60-183517 (JP, U) Actually open Showa 56-110707 (JP, U) (58) Fields investigated (Int. Cl. 7 , DB name) H01H 33 / 70-33/99 H02B 13 / 02,13 / 075 H02H 1/00-3/07
Claims (1)
され、主接点と接地回路とを備えており、前記送電線に
設けられた碍子連のアークホーンにおける逆フラッシオ
ーバーによる1線地絡事故に対して、前記送電線の両端
にある遮断器を開極した状態で高速で投入動作を行い、
前記逆フラッシオーバーの消弧後に開極動作を行う高速
再閉路接地装置において、 前記主接点には第2開極接点が電気的に直列に接続さ
れ、この第2開極接点には、前記接地回路に直接接続さ
れる第2主接触子と、前記第2開極接点の開極動作の際
にこの接点間に発生する極間アークを転流する転流接触
子部、及びこの転流接触子部に接続される抵抗体が配置
され、前記第2開極接点が、前記主接点の開極に合わせ
て開極するように構成されたことを特徴とする高速再閉
路接地装置。(57) [Claims 1] A high voltage power transmission line connected to a circuit breaker is provided in each phase and includes a main contact and a grounding circuit. In response to a one-line ground fault due to reverse flashover in the arc horn, perform closing operation at high speed with the circuit breakers at both ends of the transmission line open,
In a high-speed reclosable grounding device that performs an opening operation after the reverse flashover is extinguished, a second opening contact is electrically connected to the main contact in series, and the grounding is connected to the second opening contact. the second and main contact, the commutation contact unit for commutation poles between arc generated between the contacts upon opening operation of the second opening contact that is connected directly to the circuit, and the commutation contact A high-speed reclosable grounding device, wherein a resistor connected to the slave portion is arranged, and the second opening contact is configured to open in accordance with the opening of the main contact.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP20397892A JP3432236B2 (en) | 1992-07-30 | 1992-07-30 | High-speed reclosable grounding device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP20397892A JP3432236B2 (en) | 1992-07-30 | 1992-07-30 | High-speed reclosable grounding device |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH0654417A JPH0654417A (en) | 1994-02-25 |
JP3432236B2 true JP3432236B2 (en) | 2003-08-04 |
Family
ID=16482776
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP20397892A Expired - Fee Related JP3432236B2 (en) | 1992-07-30 | 1992-07-30 | High-speed reclosable grounding device |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP3432236B2 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20170028399A (en) | 2014-08-28 | 2017-03-13 | 미쓰비시덴키 가부시키가이샤 | High-speed contact device and switchgear equipped with same |
-
1992
- 1992-07-30 JP JP20397892A patent/JP3432236B2/en not_active Expired - Fee Related
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR20170028399A (en) | 2014-08-28 | 2017-03-13 | 미쓰비시덴키 가부시키가이샤 | High-speed contact device and switchgear equipped with same |
US10593496B2 (en) | 2014-08-28 | 2020-03-17 | Mitsubishi Electric Corporation | High-speed closing device and switchgear including high-speed closing device |
Also Published As
Publication number | Publication date |
---|---|
JPH0654417A (en) | 1994-02-25 |
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