JP2004233255A

JP2004233255A - Disconnection detecting system of distribution line

Info

Publication number: JP2004233255A
Application number: JP2003024059A
Authority: JP
Inventors: Yoshihiro Fukumoto; 佳弘福本; Koji Maeda; 耕二前田
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2003-01-31
Filing date: 2003-01-31
Publication date: 2004-08-19
Anticipated expiration: 2023-01-31
Also published as: JP4117201B2

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that a device for specifying a disconnection position of a distribution line by arranging a voltage/current measuring device on the distribution line and analyzing values obtained at each measured point conventionally determines which section of sections divided with the voltage/current measuring device generates disconnection alone, determination of the disconnection position in the section must be inspected by persons and many times are needed. <P>SOLUTION: A disconnection detecting system of the distribution line arranges the voltage/current measuring devices 1-9 on the distribution line 1, finds a difference between a positive phase voltage and reverse phase voltage obtained at each measured point as a function of a distance on the distributed line, and is provided with a disconnection point calculating device 211 for finding the distance in which the value of the difference is similar. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
この発明は、配電線の断線を検出する断線検出装置に関するものである。
【０００２】
【従来の技術】
配電線は空中配線、地中配線にかかわらず、不測の原因により断線する場合がある。この場合、早期に復旧するためには、断線した位置をできるかぎり早く発見する必要があるが、配電線は一般に全長が大変長いので、その検出は容易ではない。従来の断線検出装置においては配電線上の複数の点で測定した電流、電圧の値から、１つの配電線区間の断線を検出している。（例えば特許文献１参照）
そして、断線が検出された配電線の真の断線点は、例えば人が配電線に沿って黙視点検しつつ移動して発見する必要があるため、長時間かかり、復旧が遅れる原因となっていた。
【０００３】
また、配電線末端側に分散電源が存在する場合には、途中の配電線が断線しても必ずしも末端の電圧が大幅には変化しない場合があり、故障区間が標定できない場合があった。また、通常は高圧配電線は中性点が非接地であるため、接地インピーダンスが存在する配電線について、故障区間を標定することは考慮の対象外であった。
【０００４】
【特許文献１】
特開平２−２６６８２２号公報（第８頁、第１図）
【０００５】
【発明が解決しようとする課題】
従来の断線検出装置は以上のように構成されているので、この装置により断線区間までは自動的に検出可能であっても、断線点は検出できないという課題があった。また、配電線末端側に分散電源が存在する場合には、途中の配電線が断線しても故障区間が標定できない場合があった。また、通常は高圧配電線は中性点が非接地であるため、接地インピーダンスが存在する配電線について、故障区間を標定することは考慮されていないという課題があった。
【０００６】
この発明は上記の課題を解決するためになされたものであり、故障区間だけでなく故障点を標定できる断線検出装置を得ることを目的とする。また配電線末端側に分散電源が存在する場合でも統一的な取り扱いにより故障区間および故障点を標定できる装置を得ることを目的とする。また通常は高圧配電線は中性点が非接地であるが接地インピーダンスが存在する配電線に対しても、統一的な取り扱いにより故障区間および故障点を標定できる装置を得ることを目的とする。
【０００７】
【課題を解決するための手段】
この発明に係る配電線の断線検出装置は、複数の区間に区分した配電線の区間のそれぞれに測定点を設定する。この測定点のそれぞれに、前記配電線の前記測定点での電圧と電流とを検出し、方向も含めた正相・逆相・零相の電圧と電流を演算してデータ化し、このデータを通信線を介して外部へ伝送するセンサを配置する。
前記複数区間のそれぞれのセンサから通信線を介して前記データを受信し、前記配電線の正相電流と逆相電流と零相電流との和を演算し、前記正相電流値が零でなく、かつ、前記配電線の正相電流と逆相電流と零相電流との和が零となるとき、前記配電線に１線の断線があることを示す断線検出信号を出力する１線断線判定処理装置を備えたものである。
また、各測定点の正相電圧と逆相電圧とをもとに、各測定点の正相電圧と逆相電圧との差を求め、この差が一致する前記配電線上の位置を前記配電線上の距離の関数として求め、この位置のデータを断線位置信号として出力する第１の断線点演算装置を備えたものである。
【０００８】
【発明の実施の形態】
実施の形態１．
以下、この発明の実施の形態１の配電線の断線検出装置を図１に基づいて説明する。
図１において、配電線１上に電流・電圧を測定する電流・電圧測定装置２〜９が設置されている。電流・電圧測定装置２〜９は測定した電流・電圧を通信線１０を通じて断線判定装置１１に通信する。電流・電圧測定装置２〜９は、また、測定値を正相・逆相・零相の電圧・電流に変換する。
図２は電流・電圧測定装置２〜９と、断線判定装置１１によりデータを処理する処理ブロックの構成を説明する図である。
【０００９】
次に動作について説明する。
図３は地点９０と地点９１との間を接続する３相（ａ，ｂ，ｃ相）の配電線１のａ相の点９９に断線が発生した場合の動作を説明する図である。図で地点９０と地点９１には変圧器記号を付しているが、これは説明の都合上、区間の理解を明確にするために記載したものであり、両端にどのような機器が接続されているかは問題ではない。今、ａ相断線点９９の左側、即ち地点９０側の電圧は、右側、即ち地点９１側の電圧より３・Ｖ大きいとする。ここでＶは任意数である。断線点９９の右側のａ相、ｂ相、ｃ相の電圧をそれぞれＶ_ａ，Ｖ_ｂ，Ｖ_ｃとすると断線点左側のａ相、ｂ相、ｃ相の電圧はそれぞれＶ_ａ＋（３・Ｖ），Ｖ_ｂ，Ｖ_ｃとなる。
断線点９９の右側の零相、正相、逆相の電圧を、それぞれＶ_０，Ｖ_１，Ｖ_２とすると、断線点９９の左側の零相、正相、逆相の電圧は、それぞれ対称座標法の定義から、ａ＝ｅ^{ｊ（２π／３）}として
（Ｖ_ａ＋３Ｖ＋Ｖ_ｂ＋Ｖ_ｃ）／３＝Ｖ_０＋Ｖ −−−−−−−−−−−−−−−（１）
（Ｖ_ａ＋３Ｖ＋ａＶ_ｂ＋ａ^２Ｖ_ｃ）／３＝Ｖ_１＋Ｖ −−−−−−−−−−−−−−−（２）
（Ｖ_ａ＋３Ｖ＋ａ^２Ｖ_ｂ＋ａＶ_ｃ）／３＝Ｖ_２＋Ｖ −−−−−−−−−−−−−−−（３）
【００１０】
配電線左側の相電圧をＥ_ｓ、断線点９９からみた左側の零相、正相、逆相インピーダンスをＺ_０ｓ，Ｚ_１ｓ，Ｚ_２ｓ _、零相電流、正相電流、逆相電流をそれぞれＩ_０，Ｉ_１，Ｉ_２とすると
Ｖ_０＋Ｖ＝ −Ｚ_０ｓＩ_０ −−−−−−−−−−−−−−−（４）
Ｖ_１＋Ｖ＝Ｅ_ｓ−Ｚ_１ｓＩ_１ −−−−−−−−−−−−−−−（５）
Ｖ_２＋Ｖ＝ −Ｚ_２ｓＩ_２ −−−−−−−−−−−−−−−（６）
配電線右側の相電圧をＥ_ｒ、配電線断線点からみた右側の零相、正相、逆相インピーダンスをＺ_０ｒ，Ｚ_１ｒ，Ｚ_２ｒとすると
Ｖ_０＝Ｚ_０ｒＩ_０ −−−−−−−−−−−−−−−（７）
Ｖ_１＝Ｅ_ｒ＋Ｚ_１ｒＩ_１ −−−−−−−−−−−−−−−（８）
Ｖ_２＝Ｚ_２ｒＩ_２ −−−−−−−−−−−−−−−（９）
ａ相の電流をＩａとするとき、
Ｉ_ａ＝Ｉ_０＋Ｉ_１＋Ｉ_２
ａ相は断線しているのでＩａ＝０即ち
Ｉ_０＋Ｉ_１＋Ｉ_２＝０ −−−−−−−−−−−−−−−（１０）
【００１１】
（４），（５），（６）式から
Ｖ_０＝−Ｚ_０ＳＩ_０−Ｖ
Ｖ_１＝Ｅｓ−Ｚ_１ＳＩ_１−Ｖ
Ｖ_２＝−Ｚ_２ＳＩ_２−Ｖ
これらを（７），（８），（９）式に代入して
Ｉ_０＝−Ｖ／（Ｚ_ｏｒ＋Ｚ_ｏｓ）
Ｉ_１＝−Ｖ＋（Ｅ_Ｓ−Ｅ_ｒ）／（Ｚ_１ｒ＋Ｚ_１ｓ）
Ｉ_２＝−Ｖ／（Ｚ_２ｒ＋Ｚ_２ｓ）
ここでＺ_０＝Ｚ_０ _Ｓ＋Ｚ_０ｒ，
Ｚ_１＝Ｚ_１ｓ＋Ｚ_１ｒ，
Ｚ_２＝Ｚ_２ｓ＋Ｚ_２ｒ
Ｅ_ｓ−Ｅ_ｒ＝Ｅ
Δ ＝Ｚ_０Ｚ_１＋Ｚ_１Ｚ_２＋Ｚ_２Ｚ_０
とした上で、これを（１０）式に代入して
０＝−Ｚ_１Ｚ_２Ｖ−Ｚ_０Ｚ_２（Ｖ−Ｅ）−ＶＺ_０Ｚ_１
これより
Ｖ＝Ｚ_０Ｚ_２Ｅ／ Δ −−−−−−−−−−−−−−−（１１）
を得る。
【００１２】
また、
Ｉ_０＝ − Ｚ_２Ｅ／ Δ −−−−−−−−−−−−−−−（１２）
Ｉ_１＝（Ｚ_０＋Ｚ_２）Ｅ／ Δ −−−−−−−−−−−−−−−（１３）
Ｉ_２＝ − Ｚ_０Ｅ／ Δ −−−−−−−−−−−−−−−（１４）
となるから、（１２），（１３），（１４）式から配電線上でＩ_１＝０でない場合で、方向も含めた正相電流、逆相電流および零相電流の和がゼロ即ち
Ｉ_１＋Ｉ_２＋Ｉ_０＝０＆Ｉ_１≠０ −−−−−−−−−−−−−−−（１５）
を検出することにより配電線の１線に断線のあることを容易に検出できる。
【００１３】
なお、配電線が高圧配電線のように非接地系である場合には、零相インピーダンスは正相、逆相インピーダンスよりずっと大きくＺ_０＞＞Ｚ_１，Ｚ_０＞＞Ｚ_２となるので（１１）式は以下のようになる。
Ｖ ≒ ３ＥＺ_２／（Ｚ_１＋Ｚ_２） −−−−−−−−−−−−−−−（１６）
同様に（１２）〜（１４）式は以下のようになる。
Ｉ_０ ≒ ０ −−−−−−−−−−−−−−−（１７）
Ｉ_１ ≒ Ｅ／（Ｚ_１＋Ｚ_２） −−−−−−−−−−−−−−−（１８）
Ｉ_２ ≒ − Ｅ／（Ｚ_１＋Ｚ_２） −−−−−−−−−−−−−−−（１９）
以上に説明した演算は断線判定処理装置１１ａ（１線断線判定処理装置という）内で実行され、断線検出後は断線の有無を示す断線検出信号８７が出力される。
【００１４】
実施の形態２．
実施の形態１で説明した、Ｉ_１＋Ｉ_２＋Ｉ_０＝０＆Ｉ_１≠０を検出することにより配電線に１線の断線があることを検出した後に、断線点を区間標定する第１の方法について説明する。
（２）式および（１１）式から断線点前後で正相電圧差
Ｖ＝Ｚ_０Ｚ_２Ｅ／ Δ
が発生する。そこで複数の測定点からのデータについて、相隣る測定点間で差を求める。２つの測定点の間の区間内に断線がない場合、正相電圧差は極めて小さく、断線のある区間の両側にある測定点のデータ間には、上記の式に近い値の差が生じる。これにより最大の差を生じる区間内に断線点があると区間標定することが可能である。上記の演算処理は、断線判定処理装置１１ａ内の区間判定装置１１１（第１の区間判定装置）において実行され、判定した区間は、外部へ例えば断線区間信号８８として出力される。
図４に、横軸に配電線の距離をとり、この距離上の複数の測定点（図では例として５点）で測定した正相電圧をプロットしたものを示す。相隣る測定点間の差をとる代わりに、各測定点をつなぐ線を延長して断線地点の両側の延長線の高さの差を正相電圧差として求めても良い。この差が上記の式に示す値となる区間で断線が生じていることになる。図４において測定に誤差が少なければ、正確な計算により測定装置区間内の断線位置を特定することも可能である。しかし、正相電圧差の距離による変化は断線位置を特定するには不十分な場合もあるので区間内の位置の特定には後述する実施の形態５以後の方法が適している。
【００１５】
実施の形態３．
実施の形態１で説明した、Ｉ_１＋Ｉ_２＋Ｉ_０＝０＆Ｉ_１≠０を検出することにより配電線に１線の断線があることを検出した後に、断線点を区間標定する第２の方法について説明する。
（３）式および（１１）式から断線点前後で逆相電圧差
Ｖ＝Ｚ_０Ｚ_２Ｅ／ Δ
が発生する。そこで複数の測定点からのデータの相隣る測定点間で差を求める。２つの測定点の間の区間内に断線がない場合、逆相電圧差は極めて小さく、断線のある区間の両側にある測定点のデータ間には、上記の式に近い値の差が生じる。これにより差が最大となる区間を断線点であると区間標定することが可能である。上記の演算処理は、断線判定処理装置１１ａ内の区間判定装置１１１（第２の区間判定装置）において実行され、区間は例えば断線区間信号８８として出力される。
図５に、横軸に配電線の距離をとり、この距離上の複数の測定点（図では例として５点）で測定した逆相電圧をプロットしたものを示す。相隣る測定点間のデータの差をとる代わりに、各測定点をつなぐ線を延長して断線地点の両側の延長線の高さの差をもとめてもよい。この差が上記式に示す値となる区間で断線が生じていることになる。区間内の断線位置の特定については実施の形態２で説明したと同様である。
【００１６】
実施の形態４．
実施の形態１で説明した、Ｉ_１＋Ｉ_２＋Ｉ_０＝０＆Ｉ_１≠０を検出することにより配電線に１線の断線があることを検出した後に、断線点を区間標定する第３の方法について説明する。
（１）式および（１１）式から断線点前後で零相電圧差
Ｖ＝Ｚ_０Ｚ_２Ｅ／ Δ
が発生する。そこで複数の測定点からのデータを相隣る測定点間で差を求める。２つの測定点の間の区間内に断線がない場合、零相電圧差は極めて小さく、断線のある区間の両側にある測定点のデータ間には、上記の式に近い値の差が生じる。これにより断線点を区間標定することが可能である。
上記の演算処理は、断線判定処理装置１１ａ内の区間判定装置１１１（第３の区間判定装置）において実行され、判定した区間は、外部へ、例えば断線区間信号８８として出力される。
図６に、横軸に配電線の距離をとり、この距離上の複数の測定点（図では例として５点）で測定した逆相電圧をプロットしたものを示す。相隣る測定点間の差をとる代わりに、各測定点を繋ぐ線を延長して断線地点の両側の延長線の高さの差をもとめてもよい。この差が上記の式に示す値となる区間で断線が生じていることになる。区間内の断線位置の特定については実施の形態２で説明したと同様である。
【００１７】
実施の形態５．
上記実施の形態２〜４で説明した断線区間の標定の後、区間内の断線位置をより正確に求める第１の方法について説明する。（２），（３）式および（１１）式から断線点前後で正相電圧と逆相電圧の差が等しいため、正相電圧と逆相電圧の差を標定した断線区間の前後の複数の測定点で比較し、この差の値を配電線の距離に応じてグラフ上で延長し、この差が一致する距離点を求めることにより、断線点の位置を点標定することが可能である。
図７は正相電圧と逆相電圧の差、即ち、図３の断線位置９９の左端では（Ｖ_１＋Ｖ）−（Ｖ_２＋Ｖ）を、右端ではＶ_１−Ｖ_２を測定し、この測定をそれぞれ他端へ向かって進めた場合の各測定位置のデータの一例を示している。この値が一致する位置が断線位置である。上記の演算処理は、断線判定処理装置１１ａ内の断線点演算装置２１１（第１の断線点演算装置という）において実行され、求めた断線点は、外部へ、例えば最寄りの測定点からの距離を示す断線位置信号８９として出力される。
【００１８】
実施の形態６．
区間内の断線位置をより正確に求める第２の方法について説明する。（１），（２）式および（１１）式から断線点前後で正相電圧と零相電圧の差が等しいため、正相電圧と零相電圧の差を標定した断線区間の前後の複数の測定点で比較し、これを距離に応じてグラフ上で延長し、両者が一致する点を見つけることにより断線点を点標定することが可能である。
図８は正相電圧と零相電圧の差、即ち、図３の断線位置９９の左端では（Ｖ_１＋Ｖ）−（Ｖ_０＋Ｖ）を、右端ではＶ_１−Ｖ_０を測定し、この測定をそれぞれ他端へ向かって進めた場合の各測定位置のデータの一例を示している。この値が一致する位置が断線位置である。上記の演算処理は、断線判定処理装置１１ａ内の断線点演算装置２１１（第２の断線点演算装置という）において実行され、求めた断線点は、外部へ、例えば最寄りの測定点からの距離を示す断線位置信号８９として出力される。
【００１９】
実施の形態７．
区間内の断線位置をより正確に求める第３の方法について説明する。（１），（３）式および（１１）式から断線点前後で逆相電圧と零相電圧が等しいため、標定した断線区間の前後で、逆相電圧と零相電圧の差を複数の測定点で比較し、これをグラフ上で距離に応じて延長し、両者が一致する点を見つけることにより、断線点を点標定することが可能である。
図９は逆相電圧と零相電圧の差、即ち、図３の断線位置９９の左端では（Ｖ_２＋Ｖ）−（Ｖ_０＋Ｖ）を、右端ではＶ_２−Ｖ_０を測定し、この測定をそれぞれ他端へ向かって進めた場合の各測定位置のデータの一例を示している。この値が一致する位置が断線位置である。上記の演算処理は、断線判定処理装置１１ａ内の断線点演算装置２１１（第３の断線点演算装置という）において実行され、求めた断線点は、外部へ、例えば最寄りの測定点からの距離を示す断線位置信号８９として出力される。
【００２０】
実施の形態８．
実施の形態５〜７で、配電線上で方向も含めた逆相電流、正相電流および零相電流の和がゼロ即ちＩ_２＋Ｉ_１＋Ｉ_０＝０を検出し、また断線区間の標定をした後に、区間内の断線位置を標定する場合について説明した。上記実施の形態では、断線位置が電圧・電流測定装置の間にあるものとして説明したが、実際には配電線の最も端に設置された測定装置の、更に外側に断線点がある場合も想定される。本実施形態では、断線位置が測定点より外側（配電線の端部）にある場合でも標定できるものについて説明する。
（４），（６）式および（１２），（１４）式から断線点直前（断線点の左側即ち電源側）の正相、逆相電圧はそれぞれ
Ｖ_０ｓ＝ −Ｚ_０ｓＩ_０＝Ｚ_０ｓＺ_２Ｅ／ Δ ＝｛Ｚ_０Ｚ_２Ｅ／ Δ｝ｘ｛Ｚ_０ｓ／（Ｚ_０ｓ＋Ｚ_０ｒ）｝ −−−−−−−（２０）
Ｖ_２ｓ＝ −Ｚ_２ｓＩ_２＝Ｚ_０Ｚ_２ｓＥ／ Δ ＝｛Ｚ_０Ｚ_２Ｅ／ Δ｝ｘ｛Ｚ_２ｓ／（Ｚ_２ｓ＋Ｚ_２ｒ）｝ −−−−−−−（２１）
となるので
Ｚ_０ｓ／Ｚ_０ｒ＝Ｚ_２ｓ／Ｚ_２ｒ即ち断線点から左側を見た逆相インピーダンスと零相インピーダンスの比が、断線点から右側を見た逆相インピーダンスと零相インピーダンスの比に等しい場合は断線点直前の零相電圧Ｖ_０ｓと断線点直前の逆相電圧Ｖ_２ｓは等しい。
【００２１】
一方（７），（９）式および（１２），（１４）式から断線点直後（断線点の右側即ち負荷側）の正相、逆相電圧はそれぞれ
Ｖ_０ｒ＝Ｚ_０ｒＩ_０＝ −Ｚ_０ｒＺ_２Ｅ／ Δ ＝｛−Ｚ_０Ｚ_２Ｅ／ Δ｝ｘ｛Ｚ_０ｒ／（Ｚ_０ｓ＋Ｚ_０ｒ）｝ −−−−（２２）
Ｖ_２ｒ＝Ｚ_２ｒＩ_２＝ −Ｚ_０Ｚ_２ｒＥ／ Δ ＝｛−Ｚ_０Ｚ_２Ｅ／ Δ ｝ｘ｛Ｚ_２ｒ／（Ｚ_２ｓ＋Ｚ_２ｒ）｝ −−−−（２３）
となるので
Ｚ_０ｓ／Ｚ_０ｒ＝Ｚ_２ｓ／Ｚ_２ｒ即ち断線点から左側を見た逆相インピーダンスと零相インピーダンスの比が断線点から右側を見た逆相インピーダンスと零相インピーダンスの比に等しい場合は断線点直後の零相電圧Ｖ_０ _ｒと断線点直後の逆相電圧Ｖ_２ _ｒは等しい。
このことを利用すれば、断線が電圧・電流を検出する装置より外側にしかない場合も断線点の標定が可能な装置を得ることができる。
上記の演算処理は、断線判定処理装置１１ａ内の断線点演算装置２１１（第４の断線点演算装置という）において実行され、求めた断線点は、外部へ、例えば最寄りの測定点からの距離を示す断線位置信号８９として出力される。
図１０は、横軸の距離上に配置された各測定点において測定した零相電圧と逆相電圧との一例を示し、これを延長して両者が一致する位置を見つける場合について示している。
【００２２】
実施の形態９．
実施の形態１〜８では１線の断線の場合の検出について説明した。本実施の形態以後では、一地点において２線が断線した場合について説明する。
図１１は配電線のｂ相およびｃ相で二線断線が発生したことを示す。配電線ｂ，ｃ相で同一地点２線断線が発生したときｂ，ｃ相２線断線時の断線個所１９９と２９９でのｂ相断線点両側の電圧差を３Ｕ_ｂ、ｃ相断線点両側の電圧差を３Ｕ_ｃとする。
即ち、ｂ相断線点１９９の左側の電圧は、右側の電圧より３Ｕ_ｂ大きく、ｃ相断線点２９９の左側電圧は右側電圧より３Ｕ_ｃ大きいとする。断線点右側のａ相、ｂ相、ｃ相の電圧をそれぞれＶ_ａ，Ｖ_ｂ，Ｖ_ｃとすると、断線点１９９、２９９の左側のａ相、ｂ相、ｃ相の電圧はそれぞれＶ_ａ，Ｖ_ｂ＋３Ｕ_ｂ，Ｖ_ｃ＋３Ｕ_ｃとなる。
断線点１９９の右側の零相、正相、逆相の電圧をＶ_０ _，Ｖ_１，Ｖ_２とすると、断線点１９９の左側の零相、正相、逆相の電圧は、それぞれ対称座標法の定義からａ＝ｅ^{ｊ（２π／３）}として
（Ｖ_ａ＋Ｖ_ｂ＋３Ｕ_ｂ＋Ｖ_ｃ＋３Ｕ_ｃ）／３＝Ｖ_０＋Ｕ_ｂ＋Ｕ_ｃ −−−−−−−−−−−−−−−（２４）
（Ｖ_ａ＋ａＶ_ｂ＋３ａＵ_ｂ＋ａ^２Ｖ_ｃ＋３ａ^２Ｕ_ｃ）／３＝Ｖ_１＋ａＵ_ｂ＋ａ^２Ｕ_ｃ −−−−−−（２５）
（Ｖ_ａ＋ａ^２Ｖ_ｂ＋３ａ^２Ｕ_ｂ＋ａＶ_ｃ＋３ａＵ_ｃ）／３＝Ｖ_２＋ａ^２Ｕ_ｂ＋ａＵ_ｃ −−−−−−（２６）
が成立する。
【００２３】
配電線左側の相電圧をＥ_ｓ、断線点から左側を見た零相、正相、逆相インピーダンスをＺ_０ｓ，Ｚ_１ｓ，Ｚ_２ｓとし、零相、正相、逆相の各電流をＩ_０，Ｉ_１，Ｉ_２とすると
Ｖ_０＋Ｕ_ｂ＋Ｕ_ｃ＝ − Ｚ_０ｓＩ_０ −−−−−−−−−−−−−−−（２７）
Ｖ_１＋ａＵ_ｂ＋ａ^２Ｕ_ｃ＝Ｅ_ｓ − Ｚ_１ｓＩ_１ −−−−−−−−−−（２８）
Ｖ_２＋ａ^２Ｕ_ｂ＋ａＵ_ｃ＝ − Ｚ_２ｓＩ_２ −−−−−−−−−−−−−（２９）
配電線右側の相電圧をＥ_ｒ、配電線断線点からみた右側の零相、正相、逆相インピーダンスをＺ_０ｒ，Ｚ_１ｒ，Ｚ_２ｒとすると
Ｖ_０＝Ｚ_０ｒＩ_０ −−−−−−−−−−−−−−−（３０）
Ｖ_１＝Ｅ_ｒ＋Ｚ_１ｒＩ_１ −−−−−−−−−−（３１）
Ｖ_２＝Ｚ_２ｒＩ_２ −−−−−−−−−−−−−−−（３２）
ｂ相、ｃ相は断線しているのでＩ_ｂ＝０，Ｉ_ｃ＝０であるから
Ｉ_０＝Ｉ_１＝Ｉ_２＝Ｉ_ａ／３ −−−−−−−−−−−−−−−（３３）
【００２４】
（２７），（２８），（２９）式の左辺同士、右辺同士を合計すると
Ｖ_０＋Ｖ_１＋Ｖ_２＝− Ｚ_０ｓＩ_０＋Ｅ_ｓ − Ｚ_１ｓＩ_１ − Ｚ_２ｓＩ_２ −−−−−−−−−−−−−−−（３４）
（３０），（３１），（３２）式を（３４）式に代入して（３３）式を利用すると
Ｉ_０＝Ｉ_１＝Ｉ_２＝Ｅ／（Ｚ_０＋Ｚ_１＋Ｚ_２） −−−−−−−−−−−−−−−（３５）
ただしＥ＝Ｅ_ｓ−Ｅ_ｒ，Ｚ_０＝Ｚ_０ｓ＋Ｚ_０ｒ，Ｚ_１＝Ｚ_１ｓ＋Ｚ_１ｒ，Ｚ_２＝Ｚ_２ｓ＋Ｚ_２ｒ
断線前後の正相電圧差Ｕ_１、逆相電圧差Ｕ_２、零相電圧差Ｕ_０はそれぞれ
Ｕ_１＝（Ｅ_ｓ − Ｚ_１ｓＩ_１） − （Ｅ_ｒ＋Ｚ_１ｒＩ_１）＝Ｅ（Ｚ_０＋Ｚ_２）／（Ｚ_０＋Ｚ_１＋Ｚ_２） −−−−−−−（３６）
Ｕ_２＝ − Ｚ_２ｓＩ_２ − Ｚ_２ｒＩ_２＝ −ＥＺ_２／（Ｚ_０＋Ｚ_１＋Ｚ_２） −−−−−−−−−−−−−−−（３７）
Ｕ_０＝ − Ｚ_０ｓＩ_０ − Ｚ_０ｒＩ_０＝ −ＥＺ_０／（Ｚ_０＋Ｚ_１＋Ｚ_２） −−−−−−−−−−−−−−−（３８）
（３６），（３７），（３８）式から
Ｕ_１＋Ｕ_２＋Ｕ_０＝０ −−−−−−−−−−−−−−−（３９）
（３９）式から、左側測定点の正相電圧差Ｕ_１＝０でない場合で、左側測定点の正相電圧と右側測定点の正相電圧との差Ｕ_１と、左側測定点の逆相電圧と零相電圧の和と、右側測定点の逆相電圧と零相電圧の和との差Ｕ_２＋Ｕ_０の大きさが等しく、符号が逆、即ち
Ｕ_１＝ − （Ｕ_２＋Ｕ_０）＝Ｕ＆Ｕ_１≠０−−−−−−−−−−−−−−−（４０）
ただしＵ＝Ｅ（Ｚ_０＋Ｚ_２）／（Ｚ_０＋Ｚ_１＋Ｚ_２）
であれば、左右の測定点の間に２線断線が存在することが検出できる。
理解を助けるため、図１２に上記の状態を図示する。
【００２５】
高圧配電線では非接地系のため、零相インピーダンスは正相インピーダンス、逆相インピーダンスよりずっと大きくＺ_０＞＞Ｚ_１，Ｚ_０＞＞Ｚ_２となるので、（３６），（３７），（３８）式は以下のようになる。
Ｕ_１ ≒ Ｅ −−−−−−−−−−−−−−−（４１）
Ｕ_２ ≒ ０ −−−−−−−−−−−−−−−（４２）
Ｕ_０ ≒−Ｅ −−−−−−−−−−−−−（４３）
以上に説明した演算は、断線判定処理装置１１ａ（２断線判定処理装置という）内で実行され、断線検出後は断線の有無を示す断線検出信号８７が出力される。
【００２６】
実施の形態１０．
実施の形態９で同一地点２線断線のあることを検出した後に、その断線位置の区間を標定する方法（１線断線の場合と区別するため第４の方法という）について説明する。
（３６）式から断線点前後で正相電圧差
Ｕ_１＝Ｅ（Ｚ_０＋Ｚ_２）／（Ｚ_０＋Ｚ_１＋Ｚ_２）が発生する。
そこで、複数の測定点からのデータについて、相隣る測定点間で差を求める。２つの測定点の間の区間内に断線がない場合、正相電圧差は極めて小さく、断線のある区間の両側にある測定点のデータ間には、上記の差に近い値の差が生じる。これにより、最大の差を生じる区間内に断線点があると区間評定することが可能である。上記の演算処理は、断線判定処理装置１１ａ内の区間判定装置１１１（第４の区間判定装置）において実行され、判定した区間は、外部へ、例えば断線区間信号８８として出力される。
図１３に、横軸に配電線の距離をとり、この距離上に複数の測定点（図では例として５点）で測定した正相電圧をプロットしたものを示す。相隣る測定点の差をとる代わりに、各測定点をつなぐ線を延長して断線地点の両側の延長線の高さの差を正相電圧差として求めてもよい。この差が上記の式に示す値となる区間で断線が生じていることになる。図１３において測定に誤差が少なければ、正確な計算により測定装置区間内の断線位置を特定することも可能である。しかし、正相電圧差の距離による変化は断線位置を特定するには不十分な場合もあるので、区間内の位置の特定には後述する実施の形態１３の方法が適している。
【００２７】
実施の形態１１．
同一地点の２線断線区間を標定する第５の方法について説明する。
（３７）式から断線点前後で逆相電圧差
Ｕ_２＝ − ＥＺ_２／（Ｚ_０＋Ｚ_１＋Ｚ_２）が発生する。
そこで、複数の測定点からのデータについて、相隣る測定点間で差を求める。２つの測定点の間の区間内に断線がない場合、逆相電圧差は極めて小さく、断線のある区間の両側にある測定点のデータ間には、上記の差に近い値の差が生じる。これにより、最大の差を生じる区間内に断線点があると区間評定することが可能である。上記の演算処理は、断線判定処理装置１１ａ内の区間判定装置１１１（第５の区間判定装置）において実行され、判定した区間は、外部へ、例えば断線区間信号８８として出力される。
図１４に、横軸に配電線の距離をとり、この距離上に複数の測定点（図では例として５点）で測定した逆相電圧をプロットしたものを示す。相隣る測定点間の差をとる代わりに、各測定点をつなぐ線を延長して断線地点の両側の延長線の高さの差を逆相電圧差として求めてもよい。この差が上記の式に示す値となる区間で断線が生じていることになる。区間内の断線位置の特定については実施の形態１０で説明したのと同様である。
【００２８】
実施の形態１２．
同一地点の２線断線した区間を標定する第６の方法について説明する。
（３８）式から断線点前後で零相電圧差
Ｕ_０＝ − ＥＺ_０／（Ｚ_０＋Ｚ_１＋Ｚ_２）が発生する。
そこで、複数の測定点からのデータについて、相隣る測定点間で差を求める。２つの測定点の間の区間内に断線がない場合、零相電圧差は極めて小さく、断線のある区間の両側にある測定点のデータ間には、上記の差に近い値の差が生じる。これにより、最大の差を生じる区間内に断線点があると区間評定することが可能である。上記の演算処理は、断線判定処理装置１１ａ内の区間判定装置１１１（第６の区間判定装置）において実行され、判定した区間は、外部へ、例えば断線区間信号８８として出力される。
図１５に、横軸に配電線の距離をとり、この距離上の複数の測定点（図では例として５点）で測定した零相電圧をプロットしたものを示す。相隣る測定点間の差をとる代わりに、各測定点をつなぐ線を延長して断線地点の両側の延長線の高さの差を零相電圧差として求めてもよい。この差が上記の式に示す値となる区間で断線が生じていることになる。区間内の断線位置の特定については実施の形態１０で説明したのと同様である。
【００２９】
実施の形態１３．
実施の形態１０〜１２において、２線が断線している区間を標定した後、区間内の断線位置をもっと正確に確定する方法について説明する。（３９）式から断線点前後で方向も含めた正相電圧差と逆相電圧差と零相電圧差の和がゼロに等しい。そこで図１６に示すように断線点前後での正相電圧、逆相電圧および零相電圧の和Ｖ_１＋Ｖ_２＋Ｖ_０を複数の測定点で測定する。そして配電線の両端から測定値を順次結んだ線を延長すると、同じ値を示す一点が求められる。この点が同一地点２線断線点である。
上記の演算処理は、断線判定処理装置１１ａ内の断線点演算装置２１１（第５の断線点演算装置という）において実行され、求めた断線点は、外部へ、例えば最寄りの測定点からの距離を示す断線位置信号８９として出力される。
【００３０】
【発明の効果】
以上のように、この発明によれば、配電線における複数箇所の電圧・電流を正相電圧、逆相電圧、零相電圧、正相電流、逆相電流、零相電流に変換して処理するするように構成したので、配電線の１線断線および同一地点２線断線の故障区間が標定でき、更に、区間内における故障位置の標定も可能であるという効果が得られる。また配電線末端側に分散電源が存在する場合でも統一的な取り扱いにより故障区間および故障点を標定できる装置が得られる。また通常は高圧配電線は中性点が非接地であるが接地インピーダンスが存在しても統一的な取り扱いにより故障区間および故障点を標定できる。
【図面の簡単な説明】
【図１】この発明の全ての実施の形態における配電線の断線検出装置の構成及び配置を説明する図である。
【図２】断線判定装置と電流・電圧測定装置の内部構成と接続を説明する図である。
【図３】配電線の断線位置を説明する図である。
【図４】本発明の実施の形態２の配電線断線検出装置の動作を説明する図である。
【図５】本発明の実施の形態３の配電線断線検出装置の動作を説明する図である。
【図６】本発明の実施の形態４の配電線断線検出装置の動作を説明する図である。
【図７】本発明の実施の形態５の配電線断線検出装置の動作を説明する図である。
【図８】本発明の実施の形態６の配電線断線検出装置の動作を説明する図である。
【図９】本発明の実施の形態７の配電線断線検出装置の動作を説明する図である。
【図１０】本発明の実施の形態８の配電線断線検出装置の動作を説明する図である。
【図１１】実施の形態９〜１３における配電線の断線位置を説明する図である。
【図１２】本発明の実施の形態９の配電線断線検出装置の動作を説明する図である。
【図１３】本発明の実施の形態１０の配電線断線検出装置の動作を説明する図である。
【図１４】本発明の実施の形態１１の配電線断線検出装置の動作を説明する図である。
【図１５】本発明の実施の形態１２の配電線断線検出装置の動作を説明する図である。
【図１６】本発明の実施の形態１３の配電線断線検出装置の動作を説明する図である。
【符号の説明】
１配電線、２〜９電流・電圧を測定する装置、
１０通信線、１１断線判定装置、
１１ａ断線判定処理装置（１線断線判定処理装置又は２線断線判定処理装置）、
８７断線検出信号、８８断線区間信号、８９断線位置信号、
１１１第１〜第６区間判定装置、
２１１第１〜第５断線点演算装置。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a disconnection detection device that detects a disconnection of a distribution line.
[0002]
[Prior art]
Distribution lines may be disconnected for unexpected reasons, regardless of whether they are aerial wiring or underground wiring. In this case, it is necessary to find the position of the disconnection as soon as possible in order to recover early. However, the detection of the distribution line is not easy because the entire length of the distribution line is generally very long. In a conventional disconnection detecting device, disconnection of one distribution line section is detected from current and voltage values measured at a plurality of points on a distribution line. (For example, see Patent Document 1)
And the true disconnection point of the distribution line where the disconnection was detected, for example, it is necessary for a person to move and find along the distribution line while performing a silent inspection, which takes a long time, causing a delay in recovery. .
[0003]
In addition, when a distributed power source exists on the terminal side of the distribution line, even if the distribution line on the way is disconnected, the terminal voltage may not always change significantly, and the fault section may not be located. In addition, since the neutral point of a high-voltage distribution line is normally ungrounded, it is not considered to locate a fault section for a distribution line having a ground impedance.
[0004]
[Patent Document 1]
JP-A-2-266822 (page 8, FIG. 1)
[0005]
[Problems to be solved by the invention]
Since the conventional disconnection detecting device is configured as described above, there is a problem that the disconnection point cannot be detected even if the device can be automatically detected up to the disconnection section. Further, when a distributed power source exists at the terminal side of the distribution line, a faulty section may not be located even if the distribution line in the middle is disconnected. In addition, since the neutral point of the high-voltage distribution line is normally ungrounded, there is a problem that it is not considered to locate the fault section in the distribution line having the ground impedance.
[0006]
SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and has as its object to provide a disconnection detection device capable of locating not only a fault section but also a fault point. It is another object of the present invention to obtain a device capable of locating a fault section and a fault point by unified handling even when a distributed power source exists at the end of a distribution line. It is another object of the present invention to obtain a device capable of locating a fault section and a fault point by unified handling of a high-voltage power distribution line, even if the neutral point is ungrounded but a grounding impedance exists.
[0007]
[Means for Solving the Problems]
A distribution line disconnection detection device according to the present invention sets a measurement point in each section of a distribution line divided into a plurality of sections. At each of these measurement points, the voltage and current at the measurement point of the distribution line are detected, and the positive and negative phase and zero phase voltages and currents including the directions are calculated and converted into data. A sensor for transmitting to outside through a communication line is arranged.
The data is received from each sensor of the plurality of sections via a communication line, and a sum of a positive-phase current, a negative-phase current, and a zero-phase current of the distribution line is calculated, and the positive-phase current value is not zero. And when the sum of the positive-phase current, the negative-phase current, and the zero-phase current of the distribution line becomes zero, outputs a disconnection detection signal indicating that the distribution line has a disconnection of one line. It is provided with a processing device.
Further, based on the positive-phase voltage and the negative-phase voltage at each measurement point, a difference between the positive-phase voltage and the negative-phase voltage at each measurement point is obtained, and a position on the distribution line where the difference matches is determined on the distribution line. And a first disconnection point arithmetic unit that outputs data of this position as a disconnection position signal.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiment 1 FIG.
Hereinafter, a distribution line disconnection detection device according to a first embodiment of the present invention will be described with reference to FIG.
In FIG. 1, current / voltage measuring devices 2 to 9 for measuring current / voltage are installed on a distribution line 1. The current / voltage measuring devices 2 to 9 communicate the measured current / voltage to the disconnection judging device 11 through the communication line 10. The current / voltage measuring devices 2 to 9 also convert the measured values into positive-phase / negative-phase / zero-phase voltage / current.
FIG. 2 is a diagram illustrating a configuration of a processing block for processing data by the current / voltage measurement devices 2 to 9 and the disconnection determination device 11.
[0009]
Next, the operation will be described.
FIG. 3 is a diagram for explaining an operation when a disconnection occurs at a point 99 of the a-phase of the three-phase (a, b, c-phase) distribution line 1 connecting the point 90 and the point 91. In the figure, a point 90 and a point 91 are provided with transformer symbols for the sake of explanation, for the sake of clarity of understanding of the section, and what kind of equipment is connected to both ends. Does not matter. Now, it is assumed that the voltage on the left side of the a-phase disconnection point 99, that is, the voltage on the point 90 side is larger than the voltage on the right side, that is, the point 91 side by 3 · V. Here, V is an arbitrary number. The voltages of the a-phase, b-phase, and c-phase on the right_a, V_b, V_cThen, the voltages of the a-phase, b-phase, and c-phase on the left side of the disconnection point are each V_a+ (3 · V), V_b, V_c  Becomes
The zero-phase, positive-phase, and negative-phase voltages on the right side of₀, V₁, V₂Then, the zero-phase, positive-phase, and negative-phase voltages on the left side of the break point 99 are a = e from the definition of the symmetric coordinate method.^{j (2π / 3)}As
(V_a+ 3V + V_b+ V_c) / 3 = V₀+ V-------------------------(-)
(V_a+ 3V + aV_b+ A²V_c) / 3 = V₁+ V----------------------(-)
(V_a+ 3V + a²V_b+ AV_c) / 3 = V₂+ V----------------------(-)
[0010]
Set the phase voltage on the left side of the distribution line to E_s, The zero-phase, positive-phase, and negative-phase impedances on the left side as viewed from the disconnection point 99 are Z_0s, Z_1s, Z_2s _,Zero-phase current, positive-phase current, and negative-phase current₀, I₁, I₂Then
V₀+ V = -Z_0sI₀      −−−−−−−−−−−−−−−−− (4)
V₁+ V = E_s-Z_1sI₁      −−−−−−−−−−−−−−−−− (5)
V₂+ V = -Z_2sI₂      −−−−−−−−−−−−−−−−− (6)
Set the phase voltage on the right side of the distribution line to E_r, The zero-phase, positive-phase, and negative-phase impedance on the right side as viewed from the distribution line disconnection point_0r, Z_1r, Z_2rThen
V₀ = Z_0rI₀      −−−−−−−−−−−−−−−−− (7)
V₁ = E_r+ Z_1rI₁      −−−−−−−−−−−−−−−−− (8)
V₂ = Z_2rI₂      −−−−−−−−−−−−−−−− (9)
When the current of the a-phase is Ia,
I_a = I₀+ I₁+ I₂
Since phase a is broken, Ia = 0
I₀+ I₁+ I₂ = 0---------------------(-) (10)
[0011]
From equations (4), (5) and (6)
V₀= -Z_0SI₀-V
V₁= Es-Z_1SI₁-V
V₂= -Z_2SI₂-V
Substituting these into equations (7), (8) and (9)
I₀= -V / (Z_or+ Z_os)
I₁= −V + (E_S-E_r) / (Z_1r+ Z_1s)
I₂= -V / (Z_2r+ Z_2s)
Where Z₀  = Z₀ _S  + Z_0r,
Z₁  = Z_1s  + Z_1r,
Z₂  = Z_2s  + Z_2r
E_s-E_r= E
Δ = Z₀  Z₁  + Z₁  Z₂  + Z₂  Z₀
And then substitute this into equation (10)
0 = -Z₁Z₂V-Z₀  Z₂(VE) -VZ₀Z₁
Than this
V = Z₀  Z₂  E / Δ −−−−−−−−−−−−−−− (11)
Get.
[0012]
Also,
I₀  = -Z₂  E / Δ −−−−−−−−−−−−−−− (12)
I₁  = (Z₀  + Z₂  ) E / Δ −−−−−−−−−−−−−−− (13)
I₂  = -Z₀  E / Δ −−−−−−−−−−−−−−− (14)
From the equations (12), (13), and (14), I₁= 0, and the sum of the positive-phase current, the negative-phase current, and the zero-phase current including the direction is zero, that is,
I₁  + I₂  + I₀  = 0 & I₁≠ 0 −−−−−−−−−−−−−−−− (15)
Is detected, it can be easily detected that one of the distribution lines is broken.
[0013]
When the distribution line is an ungrounded system such as a high-voltage distribution line, the zero-phase impedance is much larger than the positive-phase impedance and the negative-phase impedance.₀  >>> Z₁, Z₀  >> Z₂Thus, equation (11) becomes as follows.
V ≒ 3EZ₂  / (Z₁+ Z₂) -------------------------------------------------------- (16)
Similarly, equations (12) to (14) are as follows.
I₀  ≒ 0 −−−−−−−−−−−−−−−− (17)
I₁  ≒ E / (Z₁+ Z₂) ---------------------------------------- (18)
I₂  ≒ -E / (Z₁+ Z₂) --------------------------- (19)
The above-described calculation is executed in the disconnection determination processing device 11a (referred to as a one-line disconnection determination processing device), and after the disconnection is detected, a disconnection detection signal 87 indicating the presence or absence of the disconnection is output.
[0014]
Embodiment 2 FIG.
I described in the first embodiment.₁  + I₂  + I₀  = 0 & I₁A first method of locating a break point in a section after detecting that there is one break in the distribution line by detecting $ 0 will be described.
From equations (2) and (11), the positive-sequence voltage difference before and after the disconnection point
V = Z₀  Z₂  E / Δ
Occurs. Therefore, a difference between adjacent measurement points is obtained for data from a plurality of measurement points. If there is no disconnection in the section between the two measurement points, the positive-sequence voltage difference is very small, and a difference close to the above equation occurs between the data of the measurement points on both sides of the section with the disconnection. Thereby, it is possible to determine the section when there is a disconnection point in the section where the maximum difference occurs. The above arithmetic processing is executed in the section determination device 111 (first section determination device) in the disconnection determination processing device 11a, and the determined section is output to the outside as, for example, a disconnection section signal 88.
FIG. 4 shows a plot of the distribution line distance on the horizontal axis, and plots the positive-sequence voltages measured at a plurality of measurement points (five points in the drawing) on this distance. Instead of taking the difference between adjacent measurement points, the line connecting the measurement points may be extended and the height difference between the extension lines on both sides of the disconnection point may be determined as the positive-phase voltage difference. This means that a disconnection has occurred in a section where this difference has the value shown in the above equation. In FIG. 4, if there is little error in the measurement, it is possible to specify the disconnection position in the measuring device section by accurate calculation. However, since the change in the positive-phase voltage difference due to the distance may not be sufficient to specify the disconnection position, the method in the fifth embodiment and subsequent embodiments described later is suitable for specifying the position in the section.
[0015]
Embodiment 3 FIG.
I described in the first embodiment.₁  + I₂  + I₀  = 0 & I₁A description will be given of a second method of locating a break point in a section after detecting that there is one break in the distribution line by detecting $ 0.
From equations (3) and (11), the negative-sequence voltage difference before and after the disconnection point
V = Z₀  Z₂  E / Δ
Occurs. Therefore, a difference is determined between adjacent measurement points of data from a plurality of measurement points. If there is no disconnection in the section between the two measurement points, the negative-sequence voltage difference is extremely small, and a difference close to the above equation occurs between the data of the measurement points on both sides of the section where the disconnection occurs. In this way, it is possible to determine the section where the difference is maximum as the break point. The above arithmetic processing is executed in the section determination device 111 (second section determination device) in the disconnection determination processing device 11a, and the section is output as, for example, a disconnection section signal 88.
FIG. 5 shows the plot of the negative-sequence voltage measured at a plurality of measurement points (five in the figure as examples) on this distance, taking the distance of the distribution line on the horizontal axis. Instead of taking the difference in data between adjacent measurement points, the line connecting the measurement points may be extended to determine the difference in height between the extension lines on both sides of the disconnection point. This means that a disconnection has occurred in a section where this difference has the value shown in the above equation. The specification of the disconnection position in the section is the same as that described in the second embodiment.
[0016]
Embodiment 4 FIG.
I described in the first embodiment.₁  + I₂  + I₀  = 0 & I₁A description will be given of a third method of locating a break point after detecting that there is one break in the distribution line by detecting $ 0.
From Equations (1) and (11), the zero-phase voltage difference before and after the disconnection point
V = Z₀  Z₂  E / Δ
Occurs. Therefore, a difference between adjacent measurement points is obtained from data from a plurality of measurement points. If there is no disconnection in the section between the two measurement points, the zero-sequence voltage difference is very small, and a difference close to the above equation occurs between the data of the measurement points on both sides of the section with the disconnection. This makes it possible to locate the disconnection point in the section.
The arithmetic processing described above is executed by the section determination device 111 (third section determination device) in the disconnection determination processing device 11a, and the determined section is output to the outside, for example, as a disconnection section signal 88.
FIG. 6 shows a plot of the negative-sequence voltage measured at a plurality of measurement points (five in the figure as examples) on this distance with the distance of the distribution line taken on the horizontal axis. Instead of taking the difference between adjacent measurement points, the line connecting the measurement points may be extended to determine the difference in height between the extension lines on both sides of the disconnection point. This means that a disconnection has occurred in a section where this difference has the value shown in the above equation. The specification of the disconnection position in the section is the same as that described in the second embodiment.
[0017]
Embodiment 5 FIG.
After locating the disconnection section described in the second to fourth embodiments, a first method for more accurately obtaining the disconnection position in the section will be described. From the equations (2), (3) and (11), the difference between the positive-phase voltage and the negative-phase voltage before and after the disconnection point is equal. By comparing the measurement points, the value of the difference is extended on the graph according to the distance of the distribution line, and the distance point at which the difference coincides is obtained, whereby the position of the disconnection point can be located.
FIG. 7 shows the difference between the positive-phase voltage and the negative-phase voltage, that is, (V) at the left end of the disconnection position 99 in FIG.₁+ V)-(V₂+ V), and V₁-V₂Are shown, and an example of data at each measurement position when this measurement is advanced toward the other end is shown. The position where this value matches is the disconnection position. The above-described arithmetic processing is executed in the disconnection point calculation device 211 (referred to as a first disconnection point calculation device) in the disconnection determination processing device 11a, and the determined disconnection point is set to the outside, for example, the distance from the nearest measurement point. It is output as the disconnection position signal 89 shown in FIG.
[0018]
Embodiment 6 FIG.
A second method for more accurately obtaining the disconnection position in the section will be described. From the equations (1), (2) and (11), since the difference between the positive-phase voltage and the zero-phase voltage before and after the disconnection point is equal, a plurality of the phases before and after the disconnection section in which the difference between the positive-phase voltage and the zero-sequence voltage is located. It is possible to compare the points at the measurement points, extend the points on the graph according to the distance, and find a point where the two coincide with each other.
FIG. 8 shows the difference between the positive-phase voltage and the zero-phase voltage, that is, (V) at the left end of the disconnection position 99 in FIG.₁+ V)-(V₀+ V), and V₁-V₀Are shown, and an example of data at each measurement position when this measurement is advanced toward the other end is shown. The position where this value matches is the disconnection position. The above-described arithmetic processing is executed in the disconnection point calculation device 211 (referred to as a second disconnection point calculation device) in the disconnection determination processing device 11a, and the determined disconnection point is set to the outside, for example, the distance from the nearest measurement point. It is output as the disconnection position signal 89 shown in FIG.
[0019]
Embodiment 7 FIG.
A third method for more accurately determining the disconnection position in the section will be described. From the equations (1), (3) and (11), since the negative-phase voltage and the zero-phase voltage are equal before and after the disconnection point, the difference between the negative-phase voltage and the zero-phase voltage is measured before and after the specified disconnection section. By comparing the points, extending the points on the graph according to the distance, and finding a point where the two coincide with each other, it is possible to locate the disconnection point.
FIG. 9 shows the difference between the negative-phase voltage and the zero-phase voltage, that is, (V) at the left end of the disconnection position 99 in FIG.₂+ V)-(V₀+ V), and V₂-V₀Are shown, and an example of data at each measurement position when this measurement is advanced toward the other end is shown. The position where this value matches is the disconnection position. The above-described arithmetic processing is executed in the disconnection point calculation device 211 (referred to as a third disconnection point calculation device) in the disconnection determination processing device 11a, and the determined disconnection point is set to the outside, for example, the distance from the nearest measurement point. It is output as the disconnection position signal 89 shown in FIG.
[0020]
Embodiment 8 FIG.
In the fifth to seventh embodiments, the sum of the negative-phase current, the positive-phase current, and the zero-phase current including the direction on the distribution line is zero, that is, I₂  + I₁  + I₀  The case where the position of the disconnection in the section is located after the detection of = 0 and the location of the disconnection section has been described has been described. In the above embodiment, the description has been given assuming that the disconnection position is between the voltage / current measuring devices. However, in practice, it is assumed that there is a disconnection point further outside the measuring device installed at the end of the distribution line. Is done. In the present embodiment, a description will be given of an apparatus that can be located even when the disconnection position is outside the measurement point (end of the distribution line).
From the equations (4), (6) and (12), (14), the positive-phase voltage and the negative-phase voltage immediately before the disconnection point (left side of the disconnection point, that is, the power supply side) are respectively
V_0s  = -Z_0sI₀  = Z_0sZ₂E / Δ = ｛Z₀Z₂E / Δ｝ x ｛Z_0s/ (Z_0s+ Z_0r)｝ −−−−−−−− (20)
V_2s  = -Z_2sI₂  = Z₀Z_2sE / Δ = ｛Z₀Z₂E / Δ｝ x ｛Z_2s/ (Z_2s+ Z_2r)｝ −−−−−−−− (21)
Because
Z_0s  / Z_0r  = Z_2s  / Z_2r  That is, when the ratio of the negative-phase impedance to the zero-phase impedance when viewed from the disconnection point to the left is equal to the ratio of the negative-phase impedance to the zero-phase impedance when viewed to the right from the disconnection point, the zero-phase voltage V_0s  And the reverse-phase voltage V immediately before the disconnection point_2sAre equal.
[0021]
On the other hand, from equations (7), (9) and (12), (14), the positive-phase and negative-phase voltages immediately after the disconnection point (to the right of the disconnection point, that is, on the load side) are respectively
V_0r  = Z_0rI₀  = -Z_0rZ₂E / Δ = ｛− Z₀Z₂E / Δ｝ x ｛Z_0r/ (Z_0s+ Z_0r)｝ −−−− (22)
V_2r  = Z_2rI₂  = -Z₀Z_2rE / Δ = ｛− Z₀Z₂E / Δ｝ x ｛Z_2r/ (Z_2s+ Z_2r)｝ −−−− (23)
Because
Z_0s  / Z_0r  = Z_2s  / Z_2r  That is, when the ratio of the negative-phase impedance and the zero-phase impedance when viewed from the disconnection point to the left is equal to the ratio between the negative-phase impedance and the zero-phase impedance when viewed from the disconnection point to the right, the zero-phase voltage V immediately after the disconnection point₀ _r  And the reverse-phase voltage V immediately after the disconnection point₂ _rAre equal.
By utilizing this fact, it is possible to obtain a device capable of locating the disconnection point even when the disconnection is only outside the device for detecting the voltage / current.
The above-described arithmetic processing is executed in the disconnection point calculation device 211 (referred to as a fourth disconnection point calculation device) in the disconnection determination processing device 11a. It is output as the disconnection position signal 89 shown in FIG.
FIG. 10 shows an example of the zero-sequence voltage and the negative-sequence voltage measured at each measurement point arranged on the distance along the horizontal axis, and shows a case in which these are extended to find a position where the two coincide.
[0022]
Embodiment 9 FIG.
In the first to eighth embodiments, detection in the case of one wire break has been described. Hereinafter, a case where two lines are disconnected at one point will be described.
FIG. 11 shows that a two-wire break has occurred in the b-phase and the c-phase of the distribution line. When two wires break at the same point in the distribution lines b and c, the voltage difference on both sides of the b-phase break point at the break points 199 and 299 at the time of the b and c two-wire breaks is 3U._b , The voltage difference on both sides of the c-phase break point is 3U_cAnd
That is, the voltage on the left side of the b-phase break point 199 is 3U higher than the voltage on the right side._bThe voltage on the left side of the c-phase break point 299 is 3U higher than the voltage on the right side._cLet's say it's big. The voltages of the a-phase, b-phase, and c-phase on the right_a, V_b, V_cThen, the voltages of the a-phase, b-phase, and c-phase on the left side of the disconnection points 199 and 299 are V_a, V_b+3 U_b, V_c  +3 U_cBecomes
The zero-phase, positive-phase, and negative-phase voltages on the right side of the disconnection point 199 are represented by V₀ _,V₁, V₂Then, the zero-phase, positive-phase, and negative-phase voltages on the left side of the disconnection point 199 are respectively a = e from the definition of the symmetric coordinate method.^{j (2π / 3)}As
(V_a+ V_b+3 U_b  + V_c+3 U_c) / 3 = V₀+ U_b  + U_c      −−−−−−−−−−−−−−−−− (24)
(V_a+ AV_b+3 aU_b  + A²V_c+ 3a²  U_c) / 3 = V₁+ AU_b  + A²U_c      −−−−−− (25)
(V_a+ A²V_b+ 3a²U_b  + AV_c+3 aU_c) / 3 = V₂+ A²U_b  + AU_c      −−−−−− (26)
Holds.
[0023]
Set the phase voltage on the left side of the distribution line to E_s, The zero-phase, positive-phase, and reverse-phase impedances as viewed from the_0s, Z_1s, Z_2sAnd the zero-phase, positive-phase, and negative-phase currents are represented by I₀, I₁, I₂Then
V₀+ U_b  + U_c  = -Z_0sI₀      −−−−−−−−−−−−−−−−− (27)
V₁+ AU_b  + A²U_c  = E_s  − Z_1sI₁      −−−−−−−−−−− (28)
V₂+ A²U_b  + AU_c  = -Z_2sI₂      −−−−−−−−−−−−−− (29)
Set the phase voltage on the right side of the distribution line to E_r, The zero-phase, positive-phase, and negative-phase impedance on the right side as viewed from the distribution line disconnection point_0r, Z_1r, Z_2rThen
V₀= Z_0rI₀      −−−−−−−−−−−−−−−−− (30)
V₁= E_r  + Z_1rI₁      −−−−−−−−−−− (31)
V₂= Z_2rI₂      −−−−−−−−−−−−−−−−− (32)
Since phase b and phase c are disconnected, I_b= 0, I_c= 0
I₀= I₁= I₂= I_a/ 3 ---------------------------------------- (33)
[0024]
When the left sides and the right sides of equations (27), (28) and (29) are summed,
V₀+ V₁+ V₂  = −Z_0sI₀ + E_s  − Z_1sI₁  − Z_2sI₂      −−−−−−−−−−−−−−−−− (34)
Substituting equations (30), (31) and (32) into equation (34) and using equation (33)
I₀  = I₁= I₂= E / (Z₀+ Z₁+ Z₂) ---------------------------------------- (35)
Where E = E_s-E_r, Z₀= Z_0s+ Z_0r, Z₁= Z_1s+ Z_1r, Z₂= Z_2s+ Z_2r
Positive phase voltage difference U before and after disconnection₁, The negative-sequence voltage difference U₂, Zero-phase voltage difference U₀Are each
U₁= (E_s  − Z_1sI₁)-(E_r+ Z_1rI₁) = E (Z₀+ Z₂) / (Z₀+ Z₁+ Z₂−−−−−−− (36)
U₂= -Z_2sI₂  − Z_2rI₂  = -EZ₂/ (Z₀+ Z₁+ Z₂) ------------------------------------------ (37)
U₀= -Z_0sI₀  − Z_0rI₀  = -EZ₀/ (Z₀+ Z₁+ Z₂) ------------------------------------------ (38)
From equations (36), (37) and (38)
U₁  + U₂  + U₀    = 0-------------------------(-) (39)
From equation (39), the positive-phase voltage difference U at the left measurement point₁= 0, the difference U between the positive phase voltage at the left measurement point and the positive phase voltage at the right measurement point₁ And the sum U of the negative-sequence voltage and the zero-sequence voltage at the left measurement point and the sum U of the negative-sequence voltage and the zero-sequence voltage at the right measurement point₂  + U₀  Are equal in magnitude and opposite in sign, ie
U₁=-(U₂  + U₀) = U & U₁≠ 0 −−−−−−−−−−−−−−−− (40)
Where U = E (Z₀+ Z₂) / (Z₀+ Z₁+ Z₂)
Then, it can be detected that there is a two-line break between the left and right measurement points.
FIG. 12 illustrates the above state for the sake of understanding.
[0025]
In a high-voltage distribution line, the zero-phase impedance is much larger than the positive-phase impedance and the negative-phase impedance because of the ungrounded system.₀  >>> Z₁, Z₀  >>> Z₂Therefore, the expressions (36), (37) and (38) are as follows.
U₁  ≒ E −−−−−−−−−−−−−−−− (41)
U₂  ≒ 0 −−−−−−−−−−−−−−− (42)
U₀  ≒ -E-----------------------(-) (43)
The calculation described above is executed in the disconnection determination processing device 11a (referred to as two disconnection determination processing devices), and after the disconnection is detected, a disconnection detection signal 87 indicating the presence or absence of the disconnection is output.
[0026]
Embodiment 10 FIG.
A method of locating the section at the disconnection position after detecting the presence of two disconnections at the same point in the ninth embodiment (referred to as a fourth method to distinguish it from the case of one-line disconnection) will be described.
From equation (36), the positive-phase voltage difference before and after the disconnection point
U₁= E (Z₀+ Z₂) / (Z₀+ Z₁+ Z₂) Occurs.
Therefore, differences between adjacent measurement points are obtained for data from a plurality of measurement points. When there is no disconnection in the section between the two measurement points, the positive-sequence voltage difference is extremely small, and a difference close to the above-described value occurs between the data of the measurement points on both sides of the section where the disconnection occurs. Thereby, it is possible to evaluate the section as having a disconnection point in the section where the maximum difference occurs. The above-described arithmetic processing is executed in the section determination device 111 (fourth section determination device) in the disconnection determination processing device 11a, and the determined section is output to the outside, for example, as a disconnection section signal 88.
FIG. 13 shows a plot of the distribution line distance on the horizontal axis and plotting the positive-sequence voltages measured at a plurality of measurement points (five points in the figure as an example) on this distance. Instead of taking the difference between adjacent measurement points, the line connecting the measurement points may be extended and the height difference between the extension lines on both sides of the disconnection point may be determined as the positive-phase voltage difference. This means that a disconnection has occurred in a section where this difference has the value shown in the above equation. In FIG. 13, if there is little error in the measurement, it is possible to specify the disconnection position in the measuring device section by accurate calculation. However, since the change in the positive-phase voltage difference due to the distance may not be sufficient to specify the disconnection position, the method of Embodiment 13 described later is suitable for specifying the position in the section.
[0027]
Embodiment 11 FIG.
A fifth method for locating a two-line disconnection section at the same point will be described.
From equation (37), the negative phase voltage difference before and after the disconnection point
U₂=-EZ₂/ (Z₀+ Z₁+ Z₂) Occurs.
Therefore, differences between adjacent measurement points are obtained for data from a plurality of measurement points. If there is no disconnection in the section between the two measurement points, the negative-sequence voltage difference is extremely small, and a difference close to the above-described value occurs between the data of the measurement points on both sides of the section where the disconnection occurs. Thereby, it is possible to evaluate the section as having a disconnection point in the section where the maximum difference occurs. The arithmetic processing described above is executed in the section determination device 111 (fifth section determination device) in the disconnection determination processing device 11a, and the determined section is output to the outside, for example, as a disconnection section signal 88.
FIG. 14 shows the distribution line distance plotted on the horizontal axis, and plotting the reverse-phase voltages measured at a plurality of measurement points (five points in the figure as an example) on this distance. Instead of taking the difference between adjacent measurement points, the line connecting the measurement points may be extended and the height difference between the extension lines on both sides of the disconnection point may be determined as the negative-phase voltage difference. This means that a disconnection has occurred in a section where this difference has the value shown in the above equation. The specification of the disconnection position in the section is the same as that described in the tenth embodiment.
[0028]
Embodiment 12 FIG.
A sixth method for locating a section where two lines are disconnected at the same point will be described.
From equation (38), the zero-phase voltage difference before and after the disconnection point
U₀=-EZ₀/ (Z₀+ Z₁+ Z₂) Occurs.
Therefore, differences between adjacent measurement points are obtained for data from a plurality of measurement points. If there is no disconnection in the section between the two measurement points, the zero-sequence voltage difference is extremely small, and a difference close to the above-described value occurs between the data of the measurement points on both sides of the section where the disconnection occurs. Thereby, it is possible to evaluate the section as having a disconnection point in the section where the maximum difference occurs. The arithmetic processing described above is executed in the section determination device 111 (sixth section determination device) in the disconnection determination processing device 11a, and the determined section is output to the outside, for example, as a disconnection section signal 88.
FIG. 15 shows a plot of the zero-sequence voltage measured at a plurality of measurement points (five points in the figure as an example) on the distance along the horizontal axis. Instead of taking the difference between adjacent measurement points, the line connecting the measurement points may be extended and the height difference between the extension lines on both sides of the disconnection point may be obtained as the zero-phase voltage difference. This means that a disconnection has occurred in a section where this difference has the value shown in the above equation. The specification of the disconnection position in the section is the same as that described in the tenth embodiment.
[0029]
Embodiment 13 FIG.
In the tenth to twelfth embodiments, a method will be described in which a section in which two lines are disconnected is located, and then a disconnection position in the section is determined more accurately. From equation (39), the sum of the positive-phase voltage difference, the negative-phase voltage difference, and the zero-phase voltage difference including the direction before and after the disconnection point is equal to zero. Therefore, as shown in FIG. 16, the sum V of the positive-phase voltage, the negative-phase voltage, and the zero-phase voltage before and after the disconnection point is obtained.₁  + V₂  + V₀    Is measured at a plurality of measurement points. When a line connecting measurement values is sequentially extended from both ends of the distribution line, one point indicating the same value is obtained. This point is the same point 2 line break point.
The above-described arithmetic processing is executed in the disconnection point calculation device 211 (referred to as a fifth disconnection point calculation device) in the disconnection determination processing device 11a, and the determined disconnection point is set to the outside, for example, the distance from the nearest measurement point. It is output as the disconnection position signal 89 shown in FIG.
[0030]
【The invention's effect】
As described above, according to the present invention, voltages and currents at a plurality of points in a distribution line are converted into a positive-phase voltage, a negative-phase voltage, a zero-phase voltage, a positive-phase current, a negative-phase current, and a zero-phase current and processed. With such a configuration, it is possible to locate a fault section in which the distribution line has a one-wire break and a two-wire break at the same point, and further, it is possible to locate a fault location in the section. Further, even when a distributed power source exists at the terminal side of the distribution line, a device that can locate a fault section and a fault point by unified handling can be obtained. Normally, the neutral point of the high-voltage distribution line is ungrounded, but even if there is a ground impedance, the fault section and the fault point can be located by unified handling.
[Brief description of the drawings]
FIG. 1 is a diagram illustrating a configuration and an arrangement of a distribution line disconnection detection device according to all embodiments of the present invention.
FIG. 2 is a diagram illustrating an internal configuration and connection of a disconnection determination device and a current / voltage measurement device.
FIG. 3 is a diagram illustrating a disconnection position of a distribution line.
FIG. 4 is a diagram illustrating an operation of a distribution line disconnection detection device according to a second embodiment of the present invention.
FIG. 5 is a diagram illustrating an operation of a distribution line disconnection detection device according to a third embodiment of the present invention.
FIG. 6 is a diagram illustrating an operation of a distribution line disconnection detection device according to a fourth embodiment of the present invention.
FIG. 7 is a diagram illustrating an operation of a distribution line disconnection detection device according to a fifth embodiment of the present invention.
FIG. 8 is a diagram illustrating the operation of a distribution line disconnection detection device according to a sixth embodiment of the present invention.
FIG. 9 is a diagram illustrating the operation of a distribution line disconnection detection device according to a seventh embodiment of the present invention.
FIG. 10 is a diagram illustrating an operation of a distribution line disconnection detection device according to an eighth embodiment of the present invention.
FIG. 11 is a diagram illustrating a disconnection position of a distribution line according to the ninth to thirteenth embodiments.
FIG. 12 is a diagram illustrating an operation of a distribution line disconnection detection device according to a ninth embodiment of the present invention.
FIG. 13 is a diagram illustrating the operation of the distribution line disconnection detection device according to the tenth embodiment of the present invention.
FIG. 14 is a diagram illustrating an operation of a distribution line disconnection detection device according to an eleventh embodiment of the present invention.
FIG. 15 is a diagram illustrating an operation of a distribution line disconnection detection device according to a twelfth embodiment of the present invention.
FIG. 16 is a diagram illustrating the operation of the distribution line disconnection detection device according to the thirteenth embodiment of the present invention.
[Explanation of symbols]
1 distribution line, 2-9 current / voltage measuring device,
10 communication line, 11 disconnection determination device,
11a disconnection determination processing device (1 line disconnection determination processing device or 2 line disconnection determination processing device),
87 disconnection detection signal, 88 disconnection section signal, 89 disconnection position signal,
111 first to sixth section determination devices,
211 first to fifth disconnection point calculation devices.

Claims

It is arranged at a measurement point set in each of the sections of the distribution line divided into a plurality of sections, detects a voltage and a current of the distribution line at the measurement point, and detects positive-phase, reverse-phase, and zero-phase voltages. And a sensor that calculates the current and converts it into data, and transmits this data to the outside via a communication line.
From each of the sensors in the plurality of sections, the data is received via the communication line, and the sum of a positive-phase current value, a negative-phase current value, and a zero-phase current value of the distribution line is calculated, and the positive-phase current is calculated. When the value is not zero and the sum of the positive-phase current value, the negative-phase current value, and the zero-phase current value becomes zero, a disconnection detection signal indicating that there is one disconnection in the distribution line is output. An apparatus for detecting a disconnection of a distribution line, comprising:

The one-line disconnection determination processing device obtains a difference between positive-phase voltages between the measurement points at both ends of each of the sections for all of the sections, and determines a disconnection of the one-line in a section where the difference is the largest. The disconnection detection device for a distribution line according to claim 1, further comprising a first section determination device that determines that there is a disconnection section and outputs a disconnection section signal.

The one-line disconnection determination processing device obtains a difference in the negative-sequence voltage between the measurement points at both ends of each of the sections for all the sections, and determines the disconnection of the one line in the section where the difference is the largest. The disconnection detection device for a distribution line according to claim 1, further comprising a second section determination device that determines that there is a disconnection section signal and outputs a disconnection section signal.

The one-line disconnection determination processing device obtains a difference in a zero-sequence voltage between the measurement points at both ends of each of the sections for all the sections, and determines that there is the disconnection in a section where the difference is the largest. 2. The distribution line disconnection detection device according to claim 1, further comprising a third section determination device that determines and outputs a disconnection interval signal.

The one-line disconnection determination processing device obtains a difference between the positive-phase voltage and the negative-phase voltage at each of the measurement points based on the positive-phase voltage and the negative-phase voltage at each of the measurement points. 5. A first disconnection point calculating device for obtaining a position on the distribution line where the values of the two coincide with each other as a function of a distance on the distribution line, and outputting data of the position as a disconnection position signal. The disconnection detection device for a distribution line according to any one of the above.

The one-line disconnection determination processing device obtains a difference between the positive-sequence voltage and the zero-sequence voltage at each of the measurement points based on the positive-sequence voltage and the zero-sequence voltage at each of the measurement points. 5. A second disconnection point calculating device for obtaining a position on the distribution line where the values of the two coincide with each other as a function of a distance on the distribution line, and outputting data of the position as a disconnection position signal. The disconnection detection device for a distribution line according to any one of the above.

The one-line disconnection determination processing device obtains a difference between the negative-phase voltage and the zero-phase voltage at each of the measurement points based on the negative-phase voltage and the zero-phase voltage at each of the measurement points, and calculates the difference. 5. A third disconnection point calculating device for determining a position on the distribution line where the values of the two coincide with each other as a function of a distance on the distribution line, and outputting data of the position as a disconnection position signal. The disconnection detection device for a distribution line according to any one of the above.

The one-line disconnection determination processing device is based on the negative-sequence voltage and the zero-sequence voltage at each of the measurement points, on the distribution line where the negative-sequence voltage and the zero-sequence voltage at each of the measurement points match. 5. The apparatus according to claim 2, further comprising a fourth disconnection point calculation device that obtains a position as a function of a distance on the distribution line, and outputs data of the position as a disconnection position signal. 6. Distribution line disconnection detector.

It is arranged at a measurement point set in each of the sections of the distribution line divided into a plurality of sections, detects a voltage and a current of the distribution line at the measurement point, and detects positive-phase, reverse-phase, and zero-phase voltages. And a sensor that calculates the current and converts it into data, and transmits this data to the outside via a communication line.
Receiving the data from the respective sensors of the plurality of sections via the communication line, from the positive-phase voltage value, the negative-phase voltage value, and the zero-phase voltage value at two adjacent measurement points on the distribution line, the difference U ₁ of the positive phase voltage value between both points, the calculated and the difference U _{2 +} U ₀ of the sum of the negative-phase voltage value and the zero-phase voltage value between both points, rather than U ₁ is zero, and ,
When U ₁ = − (U ₂ + U ₀ ), there is provided a two-wire disconnection determination processing device that outputs a disconnection detection signal indicating that there is a two-wire disconnection at the same point on the distribution line. Distribution line disconnection detection device.

The two-line disconnection determination processing device obtains the difference in the positive-sequence voltage between the measurement points at both ends of each of the sections for all the sections, and the section in which the difference is the largest indicates the disconnection of the two lines. The disconnection detection device for a distribution line according to claim 9, further comprising a fourth section determination device that determines that there is a connection and outputs a disconnection section signal.

The two-wire disconnection determination processing device obtains the difference in the negative-phase voltage between the measurement points at both ends of each of the sections for all the sections, and the section in which the difference is the largest indicates the disconnection of the two lines. The disconnection detection device for a distribution line according to claim 9, further comprising a fifth section determination device that determines that there is a disconnection section signal and outputs a disconnection section signal.

The two-line disconnection determination processing device obtains a difference in the zero-sequence voltage between the measurement points at both ends of each of the sections for all the sections. 10. The distribution line disconnection detecting apparatus according to claim 9, further comprising a sixth section determining device that determines that there is a disconnection section signal and outputs a disconnection section signal.

The two-wire disconnection determination processing device obtains a sum of the positive-sequence voltage, the negative-sequence voltage value, and the zero-sequence voltage value of each of the measurement points, and determines a position on the distribution line where the sum coincides with a distance on the distribution line. The disconnection detecting device for a distribution line according to any one of claims 10 to 12, further comprising a fifth disconnection point calculating device that obtains the position as a disconnection position signal and obtains the position data as a disconnection position signal. .