JP4365111B2

JP4365111B2 - Ground transformer equipment

Info

Publication number: JP4365111B2
Application number: JP2003033278A
Authority: JP
Inventors: 修一喜久川; 賢治土屋; 安昭鈴木; 悟梶原; 孝一村田; 良太郎花渕
Original assignee: Tokyo Electric Power Co Inc; Hitachi Ltd
Current assignee: Hitachi Ltd; Tokyo Electric Power Co Holdings Inc
Priority date: 2003-02-12
Filing date: 2003-02-12
Publication date: 2009-11-18
Anticipated expiration: 2023-02-12
Also published as: JP2004248360A

Description

【０００１】
【発明の属する技術分野】
本発明は、路上に設置され、地下に埋設した電線ケーブルにより電力の給電／配電を行う地上用変圧器装置に関する。
【０００２】
【従来の技術】
地上用変圧器装置は、特開平９−２８２９８５号公報に示されているように絶縁液に浸される変圧器を内箱に収め、その内箱を外箱に収めた構成になっている。
【０００３】
この地上用変圧器装置は、一次側の定格電圧が６ｋＶ、二次側の定格電圧が２２０Ｖ〜４００Ｖ、容量が１２５ｋＶＡ程度であるが、容量アップの傾向にある。
【０００４】
この容量アップ化にともない、電気絶縁、温度上昇、安全性、保守点検等の種々の問題に加え、地上用変圧器装置全体の大きさをコンパクトに抑えなければならない大きな技術的な問題がある。
【０００５】
なお、従来の各種機器の配置構成では変圧器容量の増加により、変圧器の外形寸法が増加するため、一次側に設地開閉器、負荷開閉器を配置するスペースが別途必要になり、地上用変圧器装置の外形寸法も自ずと増大する。一方、地上用変圧器装置に対しては、自治条例等により、その外形寸法に対して厳しい制約が設けられているので、変圧器容量の増加を図ることが困難であった。
【０００６】
【発明が解決しようとする課題】
本発明は、上記の問題に対処し、その目的とするところは全体の大きさをコンパクトに抑えることのできる地上用変圧器装置を提供せんとするものである。
【０００７】
【課題を解決するための手段】
本発明は、変圧器を内置し、かつ変圧器を浸す絶縁液が満たされている絶縁液封止用内箱と、前記変圧器の一次巻線側に外部送電系から引き込む一次側引き込み電路と、この一次側引き込み電路に設けられる接地開閉器および一次側開閉器と、前記絶縁液封止用内箱、前記引き込み電路、前記接地開閉器、および前記一次側開閉器を内置する外箱とを有し、前記絶縁液封止用内箱と前記外箱は電気的に絶縁されていることを特徴とする。
【０００８】
【発明の実施の形態】
以下に本発明の実施例ついて説明する。
【０００９】
本発明の実施例を示す図に沿って述べる。
【００１０】
まず、地上用変圧器装置の全体を縦断したところを示す図１、図２を引用する。
【００１１】
変圧器を含む各種の内部機器が納まる外箱１は、直方体の形状をしている。丈が約１４５０mm、横巾が約１１００ｍｍ、奥行きが約４５０ｍｍの寸法で、板厚が約２〜４ｍｍ程度の鋼板で作られている。外箱１の底側は底板２で閉じられ、この底板２も外箱１と同様な鋼板で形成されている。底板２は基礎枠３の基礎ボルト（図示せず）等にしっかりと締め付け固定されている。
【００１２】
絶縁液封止用内箱４は、内部に変圧器５やヒューズ６等を収めている。この絶縁液封止用内箱４の形状は、全体的には直方体の形状をしている。外箱１と同様に鋼板で作られている。
【００１３】
絶縁液封止用内箱４内の収まる変圧器５は、図２に示すようにＵ相・Ｖ相・Ｗ相の三相である。この絶縁液封止用内箱４を外箱１の天井部側に寄せるように配置することで、外箱１内には絶縁液封止用内箱４の下方に丈が約３２０mm程度の横長の下部空間Ｓ１ができる。
【００１４】
また絶縁液封止用内箱４が外箱１の右側寄せに配置されることで、外箱１内には絶縁液封止用内箱４の左片側に縦に延びる側部空間Ｓ２ができる。絶縁液封止用内箱４は左寄せに配置することも可能である。側部空間Ｓ２の横巾は２５０ｍｍ程度である。
【００１５】
絶縁液封止用内箱４は、底側が底板７で閉じられ、この底板７も絶縁液封止用内箱４と同様な鋼板で形成されている。絶縁液封止用内箱４の下端は外側に曲がるフランジ部８を有し、このフランジ部８は底板７の外周に当接する。当接面の間にシールパッキングを介在し、ボルト・ナットで締め付け固定する。
【００１６】
絶縁液封止用内箱４内には絶縁液が満たされ、変圧器５やヒューズ６が絶縁液中に浸された状態に置かれる。絶縁液は変圧器５やヒューズ６の絶縁性を高めるとともに変圧器５やヒューズ６で発生する熱を絶縁液封止用内箱４の外に放熱する機能も備えている。その放熱は絶縁液の対流によって行われる。絶縁液封止用内箱４の外周面からの放熱を高めるのに放熱フインを備えるのが望ましい。
【００１７】
変圧器５の仕様は、一次側定格電圧が２２ｋＶ、二次側定格電圧が２２０Ｖ〜４００Ｖ、容量が３５０ｋＶＡ程度のもので、従来のものに比べ、大幅に容量をアップしている。容量をアップしているにもかかわらず、一次側機器の収納スペースが、縦長の空間であるため、収納スペースの形態にあった一次側の機器配置とすることで小スペース化を図り、変圧器内部に引火点の高い絶縁液を用い、変圧器の外形寸法を抑えることで、地上用変圧器装置全体のサイズは従来のままに抑えたコンパクトなものである。
【００１８】
前記変圧器の絶縁液は、引火点が２５０℃以上の油が望ましい。従来の絶縁液は引火点が１４０℃程度の鉱物油を使用した。引火点が２５０℃以上の絶縁液を使用することで、耐熱温度の高い変圧器５やヒューズ６の使用にも耐え、地上用変圧器装置の小型化、容量アップを実現できる。引火点の高い絶縁液としては、シリコーンオイルが望ましい。
【００１９】
絶縁液封止用内箱４は支持側板８'や支持脚９等の支持部材で前記底板７に支持されている。この支持部材で絶縁液封止用内箱４が支持されることで、絶縁液封止用内箱４の下方に前記下部空間Ｓ１ができるのである。支持側板８や支持脚９等の支持部材は鋼板で出来ているので、絶縁液封止用内箱４は底板７と同電位で、対地電位（アース）になる。
【００２０】
絶縁液封止用内箱４は、前記側部空間Ｓ２に向くところが底部位置から中途高さ位置にかけて外側に膨出するヒューズ収納室１０を有する。ヒューズ収納室１０の膨出寸法は約１２５ｍｍ程度で、側部空間Ｓ２の横巾の半分程度である。ヒューズ６は、このヒューズ収納室１０に収まるので、変圧器５との間隔が開き、両者の絶縁距離を十分に保つことができる。
【００２１】
絶縁液封止用内箱４は外箱１に対し、電気的に絶縁状態が保たれるようにして置かれる。前述したように絶縁液封止用内箱４は対地に接地されているので、外箱１は対地から絶縁的に浮かされた状態になっている。絶縁液封止用内箱４内の変圧器５やヒューズ６が絶縁破壊を起こし、絶縁液封止用内箱４に一次側（外部からの給電側）の高電圧が印加されても、絶縁液封止用内箱４が対地に接地されているので、絶縁液封止用内箱４が高電位となる可能性は少ない。
【００２２】
しかし、絶縁液封止用内箱４と対地との間に抵抗が少しでも存在すると、瞬間的に高電位状態となる可能性がある。もし、外箱１が絶縁液封止用内箱４と同電位になるように接続されていると、外箱１にも高電圧が瞬間的に乗る可能性がある。外箱１は、言うまでもなく、道路の人間が触れれる状態に置かれているので、万一の安全性を考え、外箱１を絶縁液封止用内箱４から絶縁し、外箱１に高電圧が乗らないようにし、安全性を高めたのである。
【００２３】
従来の地上用変圧器装置は、一次側の給電電圧は６ｋＶであるが、本発明にあっては２０ｋＶ以上の高い高圧を使用するので、絶縁性の安全性を高めることがより望まれる。
【００２４】
図４、図５、図６は、外箱１が絶縁液封止用内箱４に対して電気的に絶縁された構成を示すものである。図５は図４のＡ部を拡大した図、図６は図４のＡ'部を拡大した図である。
【００２５】
図５に示すように絶縁液封止用内箱４の天井部４ａの上面には上方に突き出すボルト用ボス２０が二箇所に設けられる。ボルト用ボス２０の中央にはねじ穴が設けられる。外箱１の天井部１ａにはボルト用ボス２０のねじ穴に対向するところにボルト挿入穴１ｂが設けられる。ボルト挿入穴１ｂに挿入した結合用ボルト２１をボルト用ボス２０のねじ穴に螺合することで、外箱１の天井部１ａは絶縁液封止用内箱４の天井部４ａに結合される。ボルト用ボス２０と天井部１ａの間には、内側絶縁ワッシャ２２（ボルト用絶縁部材）が、結合用ボルト２１の頭部と天井部１ａとの間には、座金２３と外側絶縁ワッシャ２４（ボルト用絶縁部材）が介在されるので、外箱１は絶縁液封止用内箱４に対して電気的に絶縁が保たれるのである。
【００２６】
また外側絶縁ワッシャ２４（ボルト用絶縁部材）は、結合用ボルト２１の周囲を囲う円筒部が一体に形成されているので、外箱１のボルト挿入穴１ｂに結合用ボルト２１が直に接触することは阻止され、外箱１の絶縁液封止用内箱４に対する電気的な絶縁は確実に保たれる。また結合用ボルト２１の頭部は絶縁することが望ましい。結合用ボルト２１は絶縁液封止用内箱４と同電位であり、頭部の絶縁により、電気的な安全性は向上するのである。
【００２７】
このように外箱１の天井部と絶縁液封止用内箱４の天井部が電気的に絶縁されたまま結合固定されているので、外箱１に外力が加わっても容易に外箱１に絶縁液封止用内箱４に接触してしまうことが生じ難く、外箱１の絶縁液封止用内箱４に対する電気的な絶縁を確実に維持できる。
【００２８】
図６に示すように、底板２は外周縁に上方に立ち上がるように曲がった周縁壁部２５を有する。外箱１の下端側の内周面は、前記周縁壁部２５に合わさるように置かれる。周縁壁部２５にねじ穴を設け、外箱１の下端側にはそのねじ穴に対向するところにボルト挿入穴２６を設ける。ボルト挿入穴２６に挿入した結合用ボルト２７を周縁壁部２５のねじ穴に螺合することで、外箱１の下端側は底板２の周縁壁部２５に結合される。外箱１の下端側と周縁壁部２５の間には、内側絶縁ワッシャ２８（ボルト用絶縁部材）が、結合用ボルト２１の頭部と外箱１の下端側との間には、座金２９と外側絶縁ワッシャ３０（ボルト用絶縁部材）が介在されるので、外箱１は底板２に対して電気的に絶縁が保たれるのである。
【００２９】
このように外箱１は下端側でも電気的に絶縁されたまま結合固定されているので、電気的な絶縁を確実に、かつ良好に維持できるのである。
【００３０】
なお、結合用ボルト２７、外側絶縁ワッシャ３０は、先に述べた結合用ボルト２１、外側絶縁ワッシャ２４と同様な機能を有するものである。
【００３１】
外箱１内の下部空間Ｓ１には、主にコンサべータ４０と二次側配線装置４１が収まる。
【００３２】
図示上では明示されていないが、二次側配線装置４１が下部空間Ｓ１の前側に、コンサべータ４０が後側に置かれるように配置される。二次側配線装置４１には変圧器５で２２０Ｖ〜４００Ｖ以下程度に下げられた二次側の電力を外部に配る給電器具が備わる。
【００３３】
コンサべータ４０は、熱膨張で絶縁液封止用内箱４から放出される絶縁液を吸収し、熱収縮で絶縁液封止用内箱４内の圧力が低下したときに絶縁液封止用内箱４に戻す絶縁液封止用内箱４の圧力調整を担うものである。
【００３４】
コンサべータ４０は内部にゴム膜で封じられたタンクを有する。このタンクは管路４２を介して絶縁液封止用内箱４の上側部位と連通するようになっている。ゴム膜はタンクの反対側が大気に開放されている。
【００３５】
変圧器５の温度上昇で絶縁液封止用内箱４内の圧力が上がると、絶縁液封止用内箱４の絶縁液はゴム膜の弾力で抗してタンク内に流入する。変圧器５の温度降下で絶縁液封止用内箱４内の圧力が下がると、ゴム膜の弾力に押されてタンク内の絶縁液は戻される。
【００３６】
従来はコンサべータが絶縁液封止用内箱の上側に配置されたので、コンサべータの高さ分は地上用変圧器装置を下げることが出来なかった。外箱１内の下部空間Ｓ１にコンサべータを収めることで、地上用変圧器装置の丈を下げることが出来た。外箱１内の下部空間Ｓ１は二次側配線装置が収容される空間であったが、二次側配線装置を前側に、後側にコンサべータを配置することで、一つの下部空間Ｓ１に二次側配線とコンサべータの両方を併せて配置することが出来るのである。また二次側配線装置には開閉器等が備わるので、操作性の面でも前側に設けるのが望ましい。
【００３７】
二次側配線装置４１の絶縁ブッシング４３は、絶縁液封止用内箱４の底板７に取り付け固定される。絶縁ブッシング４３の取り付け部分には、シールパッキングを設け、絶縁液が漏れないようにしている。変圧器５の二次側配線は絶縁ブッシング４３を二次側配線装置４１に接続されている。
【００３８】
図３は接地開閉器５０および一次側開閉器５１を示すもので、この接地開閉器５０および一次側開閉器５１について述べる。
【００３９】
接地開閉器５０と一次側開閉器５１は、側部空間Ｓ２に隣り合わせに並べて置かれる。
【００４０】
接地開閉器５０は、接地用可動電極棒５２と接地用固定電極棒５３を有する。接地用固定電極５３は下側位置に、接地用可動電極棒５２は上側位置になるように置かれる。接地用固定電極５３の上端の電極と接地用可動電極棒５２の下端の電極が向き合うように置かれる。そして、向き合う両電極を介して接地用固定電極５３と接地用可動電極棒５２が一つの直線になって延在するように置かれる。
【００４１】
一次側開閉器５１は開閉用可動電極棒５４と開閉用固定電極棒５５を有する。開閉用固定電極棒５５は下側位置に、開閉用可動電極棒５４は上側位置になるように置かれる。開閉用固定電極棒５５の上側の電極と開閉用可動電極棒５４の下側の電極が向き合うように置かれる。そして、向き合う両電極を介して開閉用固定電極５５と開閉用可動電極棒５４が一つの直線になって延在するように置かれる。
【００４２】
このように接地開閉器５０と一次側開閉器５１は、隣り合わせで並べ、かつ直線に延在する方向が縦になるようにして側部空間Ｓ２に配置されるので、側部空間Ｓ２が縦に細長くても収納配置できるのである。つまり、変圧器が内置される絶縁液封止用内箱４の片脇側に縦に延びる細長の側部空間Ｓ２を接地開閉器５０および一次側開閉器５１の収納に利用することにより、外箱１の内部空間は無駄なく有効に利用することができ、地上用変圧器装置の全体の大きさをコンパクトに抑えることができる。
【００４３】
接地用可動電極棒５２は銅材で作られている。接地用可動電極棒５２は絶縁材で形成された電極棒用筒５６に挿入固定されている。電極棒用筒５６は接地用可動軸受５７に上下方向に摺動自在に支持されている。接地用可動軸受５７は絶縁材で形成されている。
【００４４】
ベローズ５８は、接地用可動軸受５７の軸受摺動隙間の気密を保つシールの機能を有する。ベローズ５８は可撓性を有する金属材で形成され、幾重に折り返した襞を有する。ベローズ５８の上端は接地用可動軸受５７側に接着材や鑞材で接着する。ベローズ５８の下端は電極棒用筒５６に接着材や鑞材で接着する。
【００４５】
接地用固定電極棒５３は支持台５９に固定支持される。支持台５９は絶縁材で形成される。接地用固定電極棒５３の下端側には接続穴６０が形成されている。
【００４６】
一次側開閉器５１の開閉用可動電極棒５４は銅材で形成されている。開閉用可動電極棒５４は上端に絶縁ブロック６１を有する。さらに絶縁ブロック６１の上端にフランジ６２を介して取り付けられる摺動体６３を有する。摺動体６３は鋼材で作られている。フランジ６２は銅材で作られている。フランジ６２と摺動体６３は接着材や鑞材で接着されている。フランジ６２と絶縁ブロック６１も接着材や鑞材で接着されている。また絶縁ブロック６１と開閉用可動電極棒５４も接着材や鑞材で接着されている。
【００４７】
このように開閉用可動電極棒５４、絶縁ブロック６１、フランジ６２、および摺動体６３は接着により一体ものになっており、一体になっている全体をとらえて開閉用可動電極棒と称することもある。
【００４８】
摺動体６３は開閉用可動軸受６４に上下方向に摺動自在に支持されている。開閉用可動軸受６４は絶縁材で作られている。
【００４９】
ベローズ６５は、開閉用可動軸受６４の軸受摺動隙間の気密を保つシールの機能を有する。ベローズ６５は、前述したベローズ５８は同様なるものである。ベローズ６５の上端は開閉用可動軸受６４側に接着材や鑞材で接着する。ベローズ６５の下端はフランジ６２に接着材や鑞材で接着する。
【００５０】
一次側開閉器５１の開閉用固定電極棒５５は支持台６６に固定支持される。支持台６６は絶縁材で形成される。開閉用固定電極棒５５の下端側には接続穴６７が形成されている。
【００５１】
開閉用固定電極棒５５の電極の近傍にはアークシール６８が取り付けられている。アークシール６８は有底筒状の形状をしている。このアークシール６８で開閉用固定電極棒５５の電極と開閉用可動電極棒５４の電極を囲い、一次側開閉器５１の遮断動作に際し、アークが大きく広がらないようにしている。
【００５２】
一次側開閉器５１の開閉用可動電極棒５４と接地開閉器５０の接地用固定電極棒５３は、可撓性導体６９で電気的に接続されている。
【００５３】
上記の一次側開閉器５１と接地開閉器５０は、少なくとも双方の電極は一つの真空容器７０内に収納されている。真空容器７０は胴体部７１、上側蓋部７２、および下側蓋部７３を有する。
【００５４】
胴体部７１、上側蓋部７２、および下側蓋部７３は、厚みが２ｍｍ程度のステンレス鋼板で形成されている。上側蓋部７２の外周側と胴体部７１の上端側、および下側蓋部７３の外周側と胴体部７１の下端側は溶接されている。上側蓋部７２は接地用可動軸受５７および開閉用可動軸受６４の外周側に気密が十分に保たれ、かつ機械的にも強度も強く取り付けられる。下側蓋部７３は支持台５９および支持台６６の外周側に気密が十分に保たれ、かつ機械的にも強度も強く取り付けられる。こうして、一次側開閉器５１と接地開閉器５０は、一つの真空容器７０に収まり、一つのものにユニット化されるのである。
【００５５】
真空容器７０内は、真空度合いが１０^-4トール（ｔｏｒｒ）〜１０^-7トール（ｔｏｒｒ）程度に保たれる。下側蓋部７３はシール弁（図示せず）を有し、このシール弁７４から内部の空気を抜いて真空にするようにしている。
【００５６】
上記のように一つのものにユニット化された一次側開閉器５１と接地開閉器５０が、前述したように側部空間Ｓ２内に縦になるようにして配置されるので、縦に細長く延びる側部空間Ｓ２に収めることができるのである。また一次側開閉器５１を隣合わせに並べ、かつ一つの真空容器７０に収めた構成にすることにより、殊のほかコンパクトになり、細長の狭いところに収めることが出来るのである。
【００５７】
ユニット化になった一次側開閉器５１と接地開閉器５は、前記ヒューズ収納室１０の上側に取り付けられる。
【００５８】
図２に示すようにヒューズ収納室１０の上部に開閉器支持台８０が備えられる。この開閉器支持台８０は絶縁材で形成され、ねじ（図示せず）でヒューズ収納室１０の上部に締め付け固定される。この開閉器支持台８０に前記下側蓋部７３が載置されるように一次側開閉器５１と接地開閉器５は取り付けられる。
【００５９】
下側蓋部７３は前記支持台５９が取り付けられる筒状受け部８１と前記支持台６６が取り付けられる筒状受け部８２を有する。開閉器支持台８０は、その筒状受け部８１が嵌る支持穴８３と、その筒状受け部８２が嵌る支持穴８４を有する。一次側開閉器５１と接地開閉器５は、支持穴８３および支持穴８４に筒状受け部８１および筒状受け部８２が嵌合して堅牢の支持されるのである。
【００６０】
前記ヒューズ６は、上端側にほぼ逆円錐台形状の上端ヒューズ支持台９０を有する。上端ヒューズ支持台９０は絶縁材で形成されている。この上端ヒューズ支持台９０の中央にヒューズ６の上側端子ピン９１が突き出すように設けられる。ヒューズ６の下端側には下端ヒューズ支持台９２を有する。ヒューズ６は、下端ヒューズ支持台９２を底板７に、上端ヒューズ支持台９０をヒューズ収納室１０の上部に取り付けることでヒューズ収納室１０に置かれるように支持される。
【００６１】
下端ヒューズ支持台９２は底板７に貫通するように取り付けられるので、シール部材（図示せず）を備えて絶縁液が漏れないようにしている。また上端ヒューズ支持台９０は、上端面が前記支持穴８４の下面周縁に当接し、上端ヒューズ支持台９０の上端周縁がヒューズ収納室１０の上部に設けた受け穴に嵌まるように置かれるので、夫々の接合面にシール部材を備えて絶縁液が漏れないようにしている。
【００６２】
一次側開閉器５１の開閉用固定電極棒５５は、ヒューズ６の上側端子ピン９１を挿入することでヒューズ６に接続される。またヒューズ６の下側から引き出される電線は変圧器５の一次側に接続される。
【００６３】
ヒューズ６は一次側開閉器５１の開閉用固定電極棒５５の真下に縦に一直線に並ぶよう備わるので、このヒューズ６を備えるヒューズ収納室１０は前記側部空間Ｓ２の下側一部を利用するように設けることができる。このような構成にすることで、外箱１内にある空間を無駄なく有効に利用でき、地上用変圧器装置をコンパクトにまとめることができる。
【００６４】
外部から引き込まれる電線ケーブル１００は、外箱１の底板２を貫通して前記側部空間Ｓ２に這わされ，前記接地用固定電極棒５３の接続穴６０に挿入して接続される。
【００６５】
この電線ケーブル１００は一次側引き込み電路を形成するもので、電線ケーブル１００、接地開閉器５０、可撓性導体６９、一次側開閉器５１、ヒューズ６、および電線等によって一次側引き込み電路は形成されている。この一次側引き込み電路は前記側部空間Ｓ２に収まるので、地上用変圧器装置はコンパクトになるのである。
【００６６】
接地開閉操作装置１１０は接地開閉器５０の上方に備わる。一次側開閉操作装置１１１は一次側開閉器５１の上方に備わる。
【００６７】
接地開閉操作装置１１０は、接地用可動電極棒５２に連結され、かつ接地用可動電極棒５２のほぼ真上になるように配置される。接地開閉操作装置１１０の操作により、接地用可動電極棒５２は上下動し、接地用可動電極棒５２の電極が接地用固定電極棒５３の電極に接離する接地開閉器５０の開閉作動が行われる。
【００６８】
一次側開閉操作装置１１１は開閉用可動電極棒に連結され、かつ開閉用可動電極棒のほぼ真上になるように配置される。一次側開閉操作装置１１１の操作により、開閉用可動電極棒は上下動し、開閉用可動電極棒の電極が開閉用固定電極棒の電極に接離する一次側開閉器５１の開閉作動が行われる。
【００６９】
接地開閉操作装置１１０および一次側開閉操作装置１１１は、接地用可動電極棒５２および開閉用可動電極棒のほぼ真上になるように配置したので、縦に細長く延びる側部空間Ｓ２に収めることができる。これにより、外箱１内にある空間を無駄なく有効に利用でき、地上用変圧器装置をコンパクトにまとめることができる。
【００７０】
一次側開閉器５１は、断路器と負荷開閉器の機能を備えている。変圧器５に負荷がかかってないときには断路器として用いられ、通常の負荷量がかかっているときには負荷開閉器として用いられる。過大な負荷がかかった場合にはヒューズ６が切れるようになる。
【００７１】
接地開閉器５０は、通常では開かれている。一次側開閉器５１を開き、地上用変圧器装置の保守点検等を行うときに接地開閉器５０は閉じられる。接地開閉器５０を閉じることで、外部の送電系から切り離され、代わりに変圧器５側が対地に設置される。これにより、変圧器５側に残留する電荷が放電され、安全に保守点検をすることができる。
【００７２】
接地開閉操作装置１１０は、一次側開閉操作装置１１１と連携されている。一次側開閉器５１が開いていないときには、接地開閉器５０を閉じることが出来ないように接地開閉操作装置１１０が拘束されるようになっている。一次側開閉器５１が開のときには、接地開閉操作装置１１０で接地開閉器５０を閉じることができ、一次側開閉器５１が閉じているときには、接地開閉操作装置１１０で接地開閉器５０を閉じることができないように接地開閉操作装置１１０と一次側開閉操作装置１１１が機械的な機構で連携されている。
【００７３】
一次側開閉器５１が閉じられているとき、誤って接地開閉器５０が閉じられることがないので、接地開閉操作装置１１０の操作ミスによる接地短絡事故を防止することができる。
【００７４】
一次側開閉器５１は、遮断作動時に電極間にアークが発生する。しかし、真空容器７０内が１０^-4トール（ｔｏｒｒ）〜１０^-7トール（ｔｏｒｒ）程度の真空に保たれているので、アークの発生を最小に、かつ短時間に抑えることができる。
【００７５】
ベローズ５８、６５は、接地用可動軸受５７、開閉用可動軸受６４の摺動隙間の高い気密を保ち、かつ開閉用可動電極棒５４および接地用可動電極棒５２の上下動に際し、伸縮して開閉用可動電極棒５４および接地用可動電極棒５２の上下動に円滑に行われるようにしたものである。このような気密および伸縮の面から可撓性を有する金属材料で襞付の形状を採用したものである。
【００７６】
ヒューズ６の下端ヒューズ支持台９２は、一次側開閉操作装置１１１に連結手段１２０を介して連結されている。しかも、ヒューズ６は過負荷で切れたときに下端ヒューズ支持台９２が下方に降下移動するようになっている。ヒューズ６の切れに伴い、連結手段１２０を介して一次側開閉操作装置１１１に操作力が加わるので、一次側開閉器５１は自動的に開かせられる。
【００７７】
このように変圧器５に異常電流が流れ、ヒューズ６が切れたときには、わざわざ一次側開閉操作装置１１１を手動操作せずとも一次側開閉器５１は自動的に開かれるので、保守点検の作業にかかり易いのである。
【００７８】
外箱１の天井部１ａには、点検用扉１３０が備わる。点検用扉１３０は開閉自在ないし取り外し自在になっている。接地開閉操作装置１１０と一次側開閉操作装置１１１の上側に対向するように点検用扉１３０は位置しているので、点検用扉１３０を開くことで、接地開閉操作装置１１０と一次側開閉操作装置１１１の上側はそっくり覗かれるようになる。接地開閉操作装置１１０および一次側開閉操作装置１１１の保守点検が容易にできるのである。
【００７９】
ここまで述べたヒューズ６、接地開閉器５０、一次側開閉器５１等は、１相分であるが、変圧器５のＵ相、Ｖ相、Ｗ相に対応するように三相分備わるもので、奥行き方向並ぶように配置される。
【００８０】
【発明の効果】
以上に述べたように、本発明は、向き合う両電極を介して一つの直線になるように延在する接地用固定電極棒と接地用可動電極棒を有する接地開閉器と、向き合う両電極を介して一つの直線になるように延在する開閉用固定電極棒と開閉用可動電極棒を有する一次側開閉器とを備え、絶縁液封止用内箱を外箱の片側寄りに配置して絶縁液封止用内箱の片脇側に縦に延びる側部空間を外箱内に形成し、この側部空間に接地開閉器と一次側開閉器を隣り合わせで並べ、かつ前記直線の延在方向が縦向きになるように配置した。これにより、地上用変圧器装置全体の大きさをコンパクトに抑えることができた。
【図面の簡単な説明】
【図１】本発明の実施例に係わるもので、地上用変圧器装置の全体を縦断した縦断面図。
【図２】本発明の実施例に係わるもので、外箱から出された内箱を縦断した縦断面図。
【図３】本発明の実施例に係わるもので、一次側開閉器および接地開閉器の縦断面図。
【図４】本発明の実施例に係わるもので、地上用変圧器装置の全体を示す縦断面図。
【図５】本発明の実施例に係わるもので、図４のＡを拡大したＡ部拡大図。
【図６】本発明の実施例に係わるもので、図４のＡを拡大したＡ‘部拡大図。
【符号の説明】
１…外箱、４…内箱、５…変圧器、Ｓ２…側部空間、５０…接地開閉器、５１…一次側開閉器、５２…接地用可動電極棒、５３…接地用固定電極棒、５４…開閉用可動電極棒、５５…開閉用固定電極棒。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a ground transformer device that feeds / distributes electric power using an electric cable installed on a road and buried underground.
[0002]
[Prior art]
As shown in Japanese Patent Laid-Open No. 9-282985, the ground transformer device has a configuration in which a transformer immersed in an insulating liquid is housed in an inner box, and the inner box is housed in an outer box.
[0003]
This terrestrial transformer device has a rated voltage on the primary side of 6 kV, a rated voltage on the secondary side of 220 V to 400 V, and a capacity of about 125 kVA, but the capacity tends to increase.
[0004]
With this increase in capacity, in addition to various problems such as electrical insulation, temperature rise, safety, maintenance and inspection, there are major technical problems that require the size of the entire ground transformer device to be kept compact.
[0005]
In addition, since the outer dimensions of the transformer increase due to the increase in transformer capacity in the arrangement configuration of various conventional devices, a separate space is required to place the ground switch and load switch on the primary side. The external dimensions of the transformer device naturally increase. On the other hand, terrestrial transformer devices are subject to strict restrictions on their outer dimensions due to self-government regulations and the like, making it difficult to increase the transformer capacity.
[0006]
[Problems to be solved by the invention]
The present invention addresses the above problems and aims to provide a ground transformer device capable of keeping the overall size compact.
[0007]
[Means for Solving the Problems]
The present inventionInner box for insulating liquid sealing, in which a transformer is installed and filled with an insulating liquid that immerses the transformer, a primary side lead-in circuit that is drawn from an external power transmission system to the primary winding side of the transformer, and this primary side A grounding switch and a primary side switch provided in the lead-in electrical circuit, the insulating liquid sealing inner box, the lead-in electrical circuit, the grounding switch, and an outer box in which the primary side switch is placed, The inner box for insulating liquid sealing and the outer box are electrically insulated.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Examples of the present invention will be described below.
[0009]
An embodiment of the present invention will be described with reference to the drawings.
[0010]
First, reference is made to FIG. 1 and FIG. 2 showing a place where the entire ground transformer device is vertically cut.
[0011]
The outer box 1 in which various internal devices including a transformer are stored has a rectangular parallelepiped shape. The length is about 1450 mm, the width is about 1100 mm, the depth is about 450 mm, and the plate thickness is about 2 to 4 mm. The bottom side of the outer box 1 is closed by a bottom plate 2, and the bottom plate 2 is also formed of a steel plate similar to the outer box 1. The bottom plate 2 is firmly fixed to a foundation bolt (not shown) of the foundation frame 3 and the like.
[0012]
The insulating liquid sealing inner box 4 houses a transformer 5, a fuse 6, and the like. The insulating liquid sealing inner box 4 has a rectangular parallelepiped shape as a whole. Like the outer box 1, it is made of a steel plate.
[0013]
The transformer 5 that fits in the insulating liquid sealing inner box 4 has three phases of U phase, V phase, and W phase as shown in FIG. By arranging the insulating liquid sealing inner box 4 so as to be close to the ceiling side of the outer box 1, the outer box 1 has a horizontally long length of about 320 mm below the insulating liquid sealing inner box 4. The lower space S1 is formed.
[0014]
Further, the insulating liquid sealing inner box 4 is arranged on the right side of the outer box 1 so that a side space S2 extending vertically to the left side of the insulating liquid sealing inner box 4 is formed in the outer box 1. . The insulating liquid sealing inner box 4 can also be arranged left-justified. The lateral width of the side space S2 is about 250 mm.
[0015]
The bottom of the insulating liquid sealing inner box 4 is closed by a bottom plate 7, and the bottom plate 7 is also formed of the same steel plate as the insulating liquid sealing inner box 4. The lower end of the insulating liquid sealing inner box 4 has a flange portion 8 that bends outward, and this flange portion 8 contacts the outer periphery of the bottom plate 7. Insert seal packing between the contact surfaces and tighten with bolts and nuts.
[0016]
The insulating liquid sealing inner box 4 is filled with the insulating liquid, and the transformer 5 and the fuse 6 are immersed in the insulating liquid. The insulating liquid enhances the insulation of the transformer 5 and the fuse 6 and also has a function of radiating heat generated by the transformer 5 and the fuse 6 to the outside of the insulating liquid sealing inner box 4. The heat radiation is performed by convection of the insulating liquid. In order to enhance heat dissipation from the outer peripheral surface of the insulating liquid sealing inner box 4, it is desirable to provide a heat dissipation fin.
[0017]
The specifications of the transformer 5 are such that the primary side rated voltage is 22 kV, the secondary side rated voltage is 220 V to 400 V, and the capacity is about 350 kVA, and the capacity is greatly increased compared to the conventional one. Despite the increased capacity, the storage space for the primary device is a vertically long space, so the primary device layout that matches the shape of the storage space reduces the space required for the transformer. By using an insulating liquid with a high flash point inside and reducing the external dimensions of the transformer, the size of the entire ground transformer device is kept compact as before.
[0018]
The insulating liquid of the transformer is preferably oil having a flash point of 250 ° C. or higher. As the conventional insulating liquid, mineral oil having a flash point of about 140 ° C. was used. By using an insulating liquid having a flash point of 250 ° C. or higher, it is possible to withstand the use of the transformer 5 and the fuse 6 having a high heat-resistant temperature, and the ground transformer device can be reduced in size and capacity. Silicone oil is desirable as the insulating liquid having a high flash point.
[0019]
The insulating liquid sealing inner box 4 is supported on the bottom plate 7 by support members such as a support side plate 8 ′ and support legs 9. By supporting the insulating liquid sealing inner box 4 with this supporting member, the lower space S <b> 1 is formed below the insulating liquid sealing inner box 4. Since the support members such as the support side plates 8 and the support legs 9 are made of steel plates, the insulating liquid sealing inner box 4 is at the same potential as the bottom plate 7 and is at ground potential (ground).
[0020]
The insulating liquid sealing inner box 4 has a fuse storage chamber 10 that bulges outward from the bottom position to the mid-height position where it faces the side space S2. The bulging dimension of the fuse storage chamber 10 is about 125 mm, which is about half of the lateral width of the side space S2. Since the fuse 6 can be accommodated in the fuse storage chamber 10, the space between the fuse 6 and the transformer 5 is increased, and the insulation distance between them can be sufficiently maintained.
[0021]
The insulating liquid sealing inner box 4 is placed with respect to the outer box 1 so as to be electrically insulated. Since the insulating liquid sealing inner box 4 is grounded to the ground as described above, the outer box 1 is in a state of being insulatively floated from the ground. Even if the transformer 5 and the fuse 6 in the insulating liquid sealing inner box 4 cause a dielectric breakdown and a high voltage on the primary side (the power supply side from the outside) is applied to the insulating liquid sealing inner box 4, insulation is achieved. Since the liquid sealing inner box 4 is grounded to the ground, there is little possibility that the insulating liquid sealing inner box 4 is at a high potential.
[0022]
However, if there is any resistance between the insulating liquid sealing inner box 4 and the ground, there is a possibility that a high potential state may be instantaneously obtained. If the outer box 1 is connected so as to have the same potential as the insulating liquid sealing inner box 4, a high voltage may be instantaneously applied to the outer box 1. Needless to say, the outer box 1 is placed in a state where it can be touched by humans on the road. Therefore, in consideration of safety, the outer box 1 is insulated from the inner box 4 for sealing the insulating liquid, The high voltage was prevented from riding and the safety was improved.
[0023]
In the conventional ground transformer device, the supply voltage on the primary side is 6 kV. However, in the present invention, since a high voltage of 20 kV or higher is used, it is more desirable to improve the insulation safety.
[0024]
4, 5, and 6 show a configuration in which the outer box 1 is electrically insulated from the insulating liquid sealing inner box 4. 5 is an enlarged view of portion A in FIG. 4, and FIG. 6 is an enlarged view of portion A ′ in FIG.
[0025]
As shown in FIG. 5, bolt bosses 20 protruding upward are provided at two locations on the upper surface of the ceiling portion 4 a of the inner casing 4 for sealing an insulating liquid. A screw hole is provided in the center of the bolt boss 20. A bolt insertion hole 1 b is provided in the ceiling portion 1 a of the outer box 1 at a location facing the screw hole of the bolt boss 20. The coupling bolt 21 inserted into the bolt insertion hole 1 b is screwed into the screw hole of the bolt boss 20, whereby the ceiling portion 1 a of the outer box 1 is coupled to the ceiling portion 4 a of the insulating liquid sealing inner box 4. . An inner insulating washer 22 (bolt insulating member) is provided between the bolt boss 20 and the ceiling 1a, and a washer 23 and an outer insulating washer 24 (between the head of the coupling bolt 21 and the ceiling 1a). Since the bolt insulation member is interposed, the outer box 1 is electrically insulated from the insulating liquid sealing inner box 4.
[0026]
Further, since the outer insulating washer 24 (bolt insulating member) is integrally formed with the cylindrical portion surrounding the coupling bolt 21, the coupling bolt 21 directly contacts the bolt insertion hole 1 b of the outer box 1. This is prevented, and the electrical insulation of the outer box 1 with respect to the inner box 4 for sealing an insulating liquid is reliably maintained. In addition, it is desirable to insulate the head of the coupling bolt 21. The coupling bolt 21 is at the same potential as the insulating liquid sealing inner box 4, and electrical safety is improved by insulating the head.
[0027]
As described above, the ceiling portion of the outer box 1 and the ceiling portion of the insulating liquid sealing inner box 4 are coupled and fixed while being electrically insulated. Therefore, even if an external force is applied to the outer box 1, the outer box 1 can be easily formed. It is difficult to cause contact with the inner casing 4 for sealing the insulating liquid, and electrical insulation of the outer casing 1 with respect to the inner casing 4 for sealing the insulating liquid can be reliably maintained.
[0028]
As shown in FIG. 6, the bottom plate 2 has a peripheral wall portion 25 bent at the outer peripheral edge so as to rise upward. The inner peripheral surface on the lower end side of the outer box 1 is placed so as to be aligned with the peripheral wall portion 25. A screw hole is provided in the peripheral wall portion 25, and a bolt insertion hole 26 is provided on the lower end side of the outer box 1 at a position facing the screw hole. The lower end side of the outer box 1 is connected to the peripheral wall portion 25 of the bottom plate 2 by screwing the connecting bolt 27 inserted into the bolt insertion hole 26 into the screw hole of the peripheral wall portion 25. An inner insulating washer 28 (bolt insulating member) is provided between the lower end side of the outer box 1 and the peripheral wall portion 25, and a washer 29 is provided between the head of the coupling bolt 21 and the lower end side of the outer box 1. Since the outer insulating washer 30 (bolt insulating member) is interposed, the outer box 1 is electrically insulated from the bottom plate 2.
[0029]
Thus, since the outer box 1 is coupled and fixed while being electrically insulated even at the lower end side, the electrical insulation can be reliably and satisfactorily maintained.
[0030]
Note that the coupling bolt 27 and the outer insulating washer 30 have the same functions as the coupling bolt 21 and the outer insulating washer 24 described above.
[0031]
In the lower space S1 in the outer box 1, the conservator 40 and the secondary side wiring device 41 are mainly accommodated.
[0032]
Although not clearly shown in the drawing, the secondary wiring device 41 is arranged on the front side of the lower space S1 and the conservator 40 is arranged on the rear side. The secondary side wiring device 41 is provided with a power supply device that distributes the secondary side power lowered to about 220V to 400V or less by the transformer 5 to the outside.
[0033]
The conservator 40 absorbs the insulating liquid released from the insulating liquid sealing inner box 4 due to thermal expansion, and seals the insulating liquid when the pressure in the insulating liquid sealing inner box 4 decreases due to thermal contraction. It is responsible for adjusting the pressure of the insulating liquid sealing inner box 4 returned to the stop inner box 4.
[0034]
The conservator 40 has a tank sealed with a rubber film. This tank communicates with the upper part of the insulating liquid sealing inner box 4 via a pipe line 42. The rubber film is open to the atmosphere on the other side of the tank.
[0035]
When the pressure in the insulating liquid sealing inner box 4 increases due to the temperature rise of the transformer 5, the insulating liquid in the insulating liquid sealing inner box 4 flows into the tank against the elasticity of the rubber film. When the pressure in the insulating liquid sealing inner box 4 drops due to the temperature drop of the transformer 5, the insulating liquid in the tank is returned by the elasticity of the rubber film.
[0036]
Conventionally, since the conservator has been arranged on the upper side of the inner box for sealing the insulating liquid, the ground transformer device could not be lowered by the height of the conservator. By placing the conservator in the lower space S1 in the outer box 1, the length of the ground transformer device could be reduced. The lower space S1 in the outer box 1 is a space in which the secondary side wiring device is accommodated. However, by arranging the secondary side wiring device on the front side and the rear side on the rear side, one lower space S1 is provided. In S1, both the secondary wiring and the conservator can be arranged together. Further, since the secondary side wiring device is provided with a switch or the like, it is desirable to provide it on the front side in terms of operability.
[0037]
The insulating bushing 43 of the secondary wiring device 41 is attached and fixed to the bottom plate 7 of the insulating liquid sealing inner box 4. A seal packing is provided at the mounting portion of the insulating bushing 43 so that the insulating liquid does not leak. The secondary side wiring of the transformer 5 has an insulating bushing 43 connected to the secondary side wiring device 41.
[0038]
FIG. 3 shows the ground switch 50 and the primary side switch 51. The ground switch 50 and the primary side switch 51 will be described.
[0039]
The ground switch 50 and the primary switch 51 are placed side by side in the side space S2.
[0040]
The ground switch 50 includes a grounding movable electrode bar 52 and a grounding fixed electrode bar 53. The grounding fixed electrode 53 is placed at the lower position, and the grounding movable electrode bar 52 is placed at the upper position. The upper electrode of the grounding fixed electrode 53 and the lower electrode of the grounding movable electrode bar 52 are placed so as to face each other. Then, the grounding fixed electrode 53 and the grounding movable electrode bar 52 are placed so as to extend in a single straight line through both facing electrodes.
[0041]
The primary side switch 51 has a movable electrode bar 54 for opening and closing and a fixed electrode bar 55 for opening and closing. The open / close fixed electrode rod 55 is placed at the lower position, and the open / close movable electrode rod 54 is placed at the upper position. The upper electrode of the open / close fixed electrode rod 55 and the lower electrode of the open / close movable electrode rod 54 are placed so as to face each other. Then, the open / close fixed electrode 55 and the open / close movable electrode rod 54 are placed so as to extend in one straight line through both facing electrodes.
[0042]
As described above, the ground switch 50 and the primary switch 51 are arranged side by side and arranged in the side space S2 such that the direction extending in a straight line is vertical, so the side space S2 is vertical. Even if it is elongated, it can be stored and arranged. That is, by using the elongated side space S2 extending vertically on one side of the insulating liquid sealing inner box 4 in which the transformer is installed, for storing the grounding switch 50 and the primary switch 51, the outside The internal space of the box 1 can be used effectively without waste, and the overall size of the ground transformer device can be kept compact.
[0043]
The grounding movable electrode bar 52 is made of a copper material. The grounding movable electrode bar 52 is inserted and fixed in an electrode bar tube 56 formed of an insulating material. The electrode rod tube 56 is supported on the grounding movable bearing 57 so as to be slidable in the vertical direction. The grounding movable bearing 57 is made of an insulating material.
[0044]
The bellows 58 has a sealing function that keeps the bearing sliding gap of the grounding movable bearing 57 airtight. The bellows 58 is formed of a metal material having flexibility, and has a plurality of folded folds. The upper end of the bellows 58 is bonded to the grounding movable bearing 57 side with an adhesive or a brazing material. The lower end of the bellows 58 is bonded to the electrode rod tube 56 with an adhesive or a brazing material.
[0045]
The grounding fixed electrode rod 53 is fixedly supported on the support base 59. The support base 59 is formed of an insulating material. A connection hole 60 is formed on the lower end side of the grounding fixed electrode rod 53.
[0046]
The movable electrode bar 54 for opening and closing the primary side switch 51 is made of a copper material. The open / close movable electrode bar 54 has an insulating block 61 at the upper end. Furthermore, a sliding body 63 attached to the upper end of the insulating block 61 via a flange 62 is provided. The sliding body 63 is made of steel. The flange 62 is made of a copper material. The flange 62 and the sliding body 63 are bonded with an adhesive or a saddle material. The flange 62 and the insulating block 61 are also bonded with an adhesive or a brazing material. The insulating block 61 and the movable electrode bar 54 for opening and closing are also bonded with an adhesive or a brazing material.
[0047]
As described above, the movable electrode bar for opening / closing 54, the insulating block 61, the flange 62, and the sliding body 63 are integrated by bonding, and may be referred to as the movable electrode bar for opening / closing in order to grasp the entire unit. .
[0048]
The sliding body 63 is supported by the open / close movable bearing 64 so as to be slidable in the vertical direction. The opening / closing movable bearing 64 is made of an insulating material.
[0049]
The bellows 65 has a seal function that keeps the bearing sliding gap of the open / close movable bearing 64 airtight. The bellows 65 is the same as the bellows 58 described above. The upper end of the bellows 65 is bonded to the opening / closing movable bearing 64 side with an adhesive or a brazing material. The lower end of the bellows 65 is bonded to the flange 62 with an adhesive or a brazing material.
[0050]
The open / close fixed electrode rod 55 of the primary side switch 51 is fixedly supported by a support base 66. The support base 66 is formed of an insulating material. A connection hole 67 is formed on the lower end side of the open / close fixed electrode rod 55.
[0051]
An arc seal 68 is attached in the vicinity of the electrode of the open / close fixed electrode rod 55. The arc seal 68 has a bottomed cylindrical shape. The arc seal 68 surrounds the electrode of the open / close fixed electrode bar 55 and the electrode of the open / close movable electrode bar 54 so that the arc does not spread greatly during the shut-off operation of the primary side switch 51.
[0052]
The movable electrode bar 54 for opening and closing of the primary side switch 51 and the fixed electrode bar 53 for grounding of the ground switch 50 are electrically connected by a flexible conductor 69.
[0053]
In the primary side switch 51 and the ground switch 50, at least both electrodes are housed in a single vacuum vessel 70. The vacuum container 70 has a body portion 71, an upper lid portion 72, and a lower lid portion 73.
[0054]
The body portion 71, the upper lid portion 72, and the lower lid portion 73 are formed of a stainless steel plate having a thickness of about 2 mm. The outer peripheral side of the upper lid portion 72 and the upper end side of the body portion 71, and the outer peripheral side of the lower lid portion 73 and the lower end side of the body portion 71 are welded. The upper lid 72 is attached to the outer peripheral side of the grounding movable bearing 57 and the opening / closing movable bearing 64 with sufficient airtightness and mechanically and strongly attached. The lower lid portion 73 is sufficiently hermetically sealed on the outer peripheral sides of the support base 59 and the support base 66 and is mechanically and strongly attached. Thus, the primary side switch 51 and the ground switch 50 are housed in one vacuum vessel 70 and unitized into one unit.
[0055]
In the vacuum vessel 70, the degree of vacuum is 10^-FourTorr to 10^-7It is kept at about torr. The lower lid portion 73 has a seal valve (not shown), and the internal air is extracted from the seal valve 74 to make a vacuum.
[0056]
Since the primary side switch 51 and the grounding switch 50 unitized as one unit as described above are arranged vertically in the side space S2 as described above, the side that is elongated in the vertical direction. It can be stored in the subspace S2. Further, by arranging the primary side switches 51 next to each other and housed in one vacuum vessel 70, it becomes particularly compact and can be housed in a narrow and narrow place.
[0057]
The unitary primary switch 51 and ground switch 5 are attached to the upper side of the fuse storage chamber 10.
[0058]
As shown in FIG. 2, a switch support base 80 is provided in the upper part of the fuse storage chamber 10. The switch support base 80 is made of an insulating material, and is fastened and fixed to the upper portion of the fuse housing chamber 10 with screws (not shown). The primary side switch 51 and the ground switch 5 are attached so that the lower lid 73 is placed on the switch support base 80.
[0059]
The lower lid portion 73 has a cylindrical receiving portion 81 to which the support stand 59 is attached and a cylindrical receiving portion 82 to which the support stand 66 is attached. The switch support base 80 has a support hole 83 into which the cylindrical receiving portion 81 fits and a support hole 84 into which the cylindrical receiving portion 82 fits. The primary side switch 51 and the ground switch 5 are firmly supported by fitting the cylindrical receiving portion 81 and the cylindrical receiving portion 82 into the support hole 83 and the support hole 84.
[0060]
The fuse 6 has an upper end fuse support 90 having a substantially inverted truncated cone shape on the upper end side. The upper end fuse support 90 is made of an insulating material. The upper terminal pin 91 of the fuse 6 is provided so as to protrude in the center of the upper end fuse support 90. A lower end fuse support 92 is provided on the lower end side of the fuse 6. The fuse 6 is supported so as to be placed in the fuse storage chamber 10 by attaching the lower end fuse support 92 to the bottom plate 7 and the upper end fuse support 90 to the upper part of the fuse storage chamber 10.
[0061]
Since the lower end fuse support 92 is attached so as to penetrate the bottom plate 7, a sealing member (not shown) is provided so that the insulating liquid does not leak. Further, the upper end fuse support 90 is placed so that the upper end surface abuts the lower surface periphery of the support hole 84 and the upper end periphery of the upper end fuse support 90 fits into a receiving hole provided in the upper portion of the fuse storage chamber 10. Each of the joint surfaces is provided with a seal member so that the insulating liquid does not leak.
[0062]
The fixed electrode bar 55 for opening / closing the primary side switch 51 is connected to the fuse 6 by inserting the upper terminal pin 91 of the fuse 6. An electric wire drawn from the lower side of the fuse 6 is connected to the primary side of the transformer 5.
[0063]
Since the fuses 6 are arranged in a straight line vertically below the open / close fixed electrode rod 55 of the primary side switch 51, the fuse storage chamber 10 including the fuses 6 uses a part of the lower side of the side space S2. Can be provided. With such a configuration, the space in the outer box 1 can be effectively used without waste, and the ground transformer device can be compactly assembled.
[0064]
The electric wire cable 100 drawn from the outside passes through the bottom plate 2 of the outer box 1 and is wound in the side space S2, and is inserted into the connection hole 60 of the grounding fixed electrode rod 53 and connected thereto.
[0065]
The electric cable 100 forms a primary-side lead-in electric circuit, and the primary-side lead-in electric circuit is formed by the electric cable 100, the grounding switch 50, the flexible conductor 69, the primary-side switch 51, the fuse 6, the electric wire, and the like. ing. Since this primary side lead-in electric circuit fits in the said side space S2, the ground transformer apparatus becomes compact.
[0066]
The ground switch operating device 110 is provided above the ground switch 50. The primary side opening / closing operation device 111 is provided above the primary side switch 51.
[0067]
The ground opening / closing operation device 110 is connected to the grounding movable electrode bar 52 and disposed so as to be almost directly above the grounding movable electrode bar 52. By the operation of the ground opening / closing operation device 110, the grounding movable electrode bar 52 moves up and down, and the opening / closing operation of the grounding switch 50 in which the electrode of the grounding movable electrode bar 52 contacts and separates from the electrode of the grounding fixed electrode bar 53 is performed. Is called.
[0068]
The primary side opening / closing operation device 111 is connected to the opening / closing movable electrode rod and is disposed so as to be almost directly above the opening / closing movable electrode rod. By operating the primary side opening / closing operation device 111, the movable electrode bar for opening and closing moves up and down, and the opening and closing operation of the primary side switch 51 in which the electrode of the movable electrode bar for opening and closing contacts and separates from the electrode of the fixed electrode bar for opening and closing is performed. .
[0069]
Since the ground opening / closing operation device 110 and the primary side opening / closing operation device 111 are arranged so as to be almost directly above the grounding movable electrode rod 52 and the opening / closing movable electrode rod, they can be accommodated in the side space S2 that is elongated in the vertical direction. it can. Thereby, the space in the outer box 1 can be used effectively without waste, and the ground transformer device can be compactly assembled.
[0070]
The primary side switch 51 has functions of a disconnect switch and a load switch. When the transformer 5 is not loaded, it is used as a disconnect switch, and when a normal load is applied, it is used as a load switch. When an excessive load is applied, the fuse 6 is blown.
[0071]
The ground switch 50 is normally opened. The grounding switch 50 is closed when the primary side switch 51 is opened and maintenance of the ground transformer device is performed. By closing the ground switch 50, it is disconnected from the external power transmission system, and instead, the transformer 5 side is installed on the ground. Thereby, the electric charge which remains on the transformer 5 side is discharged, and maintenance inspection can be performed safely.
[0072]
The ground opening / closing operation device 110 is linked to the primary side opening / closing operation device 111. When the primary side switch 51 is not open, the ground switching operation device 110 is restrained so that the ground switch 50 cannot be closed. When the primary switch 51 is open, the ground switch 50 can be closed by the ground switch device 110. When the primary switch 51 is closed, the ground switch 50 is closed by the ground switch device 110. The ground opening / closing operation device 110 and the primary side opening / closing operation device 111 are linked with each other by a mechanical mechanism.
[0073]
Since the earthing switch 50 is not accidentally closed when the primary side switch 51 is closed, a grounding short circuit accident due to an operation mistake of the earthing switching operation device 110 can be prevented.
[0074]
In the primary side switch 51, an arc is generated between the electrodes during the shut-off operation. However, the inside of the vacuum vessel 70 is 10^-FourTorr to 10^-7Since a vacuum of about torr is maintained, generation of arc can be minimized and suppressed in a short time.
[0075]
The bellows 58, 65 maintain a high airtightness in the sliding clearance between the grounding movable bearing 57 and the opening / closing movable bearing 64, and expand and contract when the opening / closing movable electrode bar 54 and the grounding movable electrode bar 52 move up and down. The movable electrode rod 54 for grounding and the movable electrode rod 52 for grounding are smoothly moved up and down. This is a metal material having flexibility in terms of airtightness and expansion / contraction, and adopts a brazed shape.
[0076]
The lower end fuse support 92 of the fuse 6 is connected to the primary side opening / closing operation device 111 via a connecting means 120. Moreover, when the fuse 6 is blown by overload, the lower end fuse support 92 moves downward. As the fuse 6 is blown, an operating force is applied to the primary side opening / closing operation device 111 via the connecting means 120, so that the primary side switch 51 is automatically opened.
[0077]
Thus, when an abnormal current flows through the transformer 5 and the fuse 6 is blown, the primary side switch 51 is automatically opened without manually operating the primary side switch operating device 111. It is easy to take.
[0078]
An inspection door 130 is provided on the ceiling 1 a of the outer box 1. The inspection door 130 can be opened and closed or removed. Since the inspection door 130 is positioned so as to face the upper side of the ground opening / closing operation device 110 and the primary side opening / closing operation device 111, the grounding opening / closing operation device 110 and the primary side opening / closing operation device are opened by opening the inspection door 130. The upper side of 111 can be looked into. Maintenance and inspection of the ground opening / closing operation device 110 and the primary side opening / closing operation device 111 can be facilitated.
[0079]
The fuse 6, the ground switch 50, the primary switch 51, etc. described so far are for one phase, but are provided for three phases so as to correspond to the U phase, V phase, and W phase of the transformer 5. Are arranged in the depth direction.
[0080]
【The invention's effect】
As described above, the present invention includes a grounding switch having a grounding fixed electrode bar and a grounding movable electrode bar extending so as to form a straight line through both facing electrodes, and both facing electrodes. And a primary-side switch having a movable electrode bar for opening and closing, and an insulating liquid sealing inner box is arranged near one side of the outer box for insulation. A side space extending vertically on one side of the inner box for liquid sealing is formed in the outer box, and a grounding switch and a primary side switch are arranged side by side in this side space, and the extending direction of the straight line Was placed in a vertical orientation. As a result, the size of the entire ground transformer device could be kept compact.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of an entire ground transformer device according to an embodiment of the present invention.
FIG. 2 is a longitudinal sectional view of the inner box taken out from the outer box, according to the embodiment of the present invention.
FIG. 3 is a longitudinal sectional view of a primary side switch and a grounding switch according to an embodiment of the present invention.
FIG. 4 is a longitudinal sectional view showing the entire ground transformer device according to an embodiment of the present invention.
FIG. 5 is an enlarged view of a part A, which is an enlarged view of A of FIG. 4, according to the embodiment of the present invention.
6 relates to the embodiment of the present invention, and is an enlarged view of a portion A ′ in which A in FIG. 4 is enlarged.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Outer box, 4 ... Inner box, 5 ... Transformer, S2 ... Side space, 50 ... Grounding switch, 51 ... Primary switch, 52 ... Movable electrode rod for grounding, 53 ... Fixed electrode rod for grounding, 54: movable electrode rod for opening and closing, 55: fixed electrode rod for opening and closing.

Claims

Inner box for insulating liquid sealing, in which a transformer is installed and filled with an insulating liquid that immerses the transformer, a primary side lead-in circuit that is drawn from an external power transmission system to the primary winding side of the transformer, and this primary side A grounding switch and a primary side switch provided in the lead-in electrical circuit, the insulating liquid sealing inner box, the lead-in circuit, the grounding switch, and an outer box in which the primary side switch is placed, and the outer box A bottom plate that is a separate member from the outer box provided on the bottom side, and a support member such as a support leg that is interposed to support the insulating liquid sealing inner box on the bottom plate ,
In the ground transformer device wherein the insulating liquid sealing inner box and the outer box are electrically insulated ,
A bolt boss projecting upward is provided on the top surface of the ceiling of the insulating liquid sealing inner box,
An inner insulating washer for the ceiling portion is interposed between the upper end surface of the boss for the bolt and the inside of the ceiling portion of the outer box,
The bolt boss is provided with a screw hole for the boss,
The ceiling portion of the outer box is provided with a bolt insertion hole for the ceiling portion where it faces the screw hole for the boss,
The coupling bolt for the ceiling part to be inserted into the bolt insertion hole for the ceiling part is screwed into the screw hole for the boss, and the coupling bolt for the ceiling part is electrically insulated from the outer box. An outer insulating washer for the ceiling part is interposed between the coupling bolt for the ceiling part and the outside of the ceiling part of the outer box,
The outer peripheral edge of the bottom plate is provided with a peripheral wall that rises upward and meets the inner peripheral surface of the lower end side of the outer box,
An inner insulating washer for the lower part is interposed between the inner peripheral surface on the lower end side of the outer box and the outer peripheral surface of the peripheral wall part,
A screw hole for a peripheral wall portion is provided in the peripheral wall portion, and a bolt insertion hole for a lower end is provided at a position facing the screw hole for the peripheral wall portion on the lower end side of the outer box,
A lower coupling bolt that is inserted into the lower end bolt insertion hole is screwed into the peripheral wall portion screw hole, and the lower coupling bolt is electrically insulated from the outer box. An outer insulating washer for the ground is interposed between the lower connecting bolt and the outer peripheral surface on the lower end side of the outer box .

The ground transformer device according to claim 1,
The outer insulating washer for the ceiling portion is integrated with a cylindrical portion surrounding the coupling bolt for the ceiling portion, and the outer insulating washer for the lower portion is integrally formed with a cylindrical portion surrounding the periphery of the coupling bolt for the lower portion. Transformer device for the ground characterized by being formed into.

The ground transformer device according to claim 1,
The ground transformer device , wherein the outer box, the inner box for sealing an insulating liquid, the bottom plate, and the support member are made of a metal material including a steel plate .