JP4301353B2

JP4301353B2 - Method and apparatus for detecting and locating faults in communication cables for remote monitoring and control of wired distribution lines

Info

Publication number: JP4301353B2
Application number: JP2000005372A
Authority: JP
Inventors: 勲夫森山; 辰己幸野; 博史弥永; 洋飯田; 裕二渡邊; 晃笹渕; 洋典神田; 恭幸有吉; 智海石原
Original assignee: Kyushu Electric Power Co Inc
Current assignee: Kyushu Electric Power Co Inc
Priority date: 2000-01-14
Filing date: 2000-01-14
Publication date: 2009-07-22
Anticipated expiration: 2020-01-14
Also published as: JP2001196980A

Description

【０００１】
【発明の属する技術分野】
本発明は、配電系統の営業所に通常は設置された親局と配電線に対応する適当箇所に設置された複数の子局とを結ぶように敷設され、当該配電系統の遠隔監視および制御を行なうために用いられる有線式配電線遠方監視制御用通信ケーブルの障害点探査方法および装置に関し、特に親局と複数の子局間の通信媒体として使用される遠方監視制御用通信ケーブルに生ずる地絡、短絡、混触、断線などの各種障害の発生地点を探査する方法および装置に関する。
【０００２】
また本発明は、前記通信ケーブルに、前述のような各種障害が発生したことを検出したときに、障害発生位置をさらに精細に標定する方法および装置に関し、特に前記障害が間欠的である場合にも確実に障害発生位置を標定できる障害発生位置標定方法および装置に関する。
【０００３】
【従来の技術】
配電系統の営業所に設置された親局と配電線の適当箇所に設置された複数の子局とを１対ｎ方式で結ぶように通信ケーブルを敷設しておき、相互間で各種制御信号や情報を授受して当該配電系統の監視および制御を行なうこことが行なわれている。
【０００４】
図５は従来の代表的な有線式配電線遠方監視制御系統の１例を示す概略図である。配電系統の営業所内に設置された親局１と配電線の適当箇所に設置された複数（１親局当たり、例えば最大２３０局程度）の子局５とは、２対４線式遠方監視制御用通信ケーブル（以下、「遠制ケーブル」と略する）２によって１対ｎ方式で接続される。遠制ケーブル２の適所には通信ポット３ａ、３ｂ、３ｃ…が設けられ、そこから子局５への遠制ケーブルが分岐される。各子局５は配電線７に設置された高圧開閉器６に対応して設けられ、遠制ケーブル２を介して親局から送信される制御信号にしたがって前記開閉器６の開閉を制御し、またその開閉状態を監視して必要な情報を親局１へ伝送する。このようにして、親局１すなわち営業所ではその管轄下にある各子局５や高圧開閉器６の状態を常時把握することができる。
【０００５】
いまＦ１の箇所で遠制ケーブル２に障害が生じた場合は、例えば次のような手順で障害箇所の特定が行なわれる。
ａ．子局５からの返信状態に基づき、障害箇所のおおまかな絞り込みを行なう。
ｂ．絞り込んだ領域内のｘ印２ａ〜２ｄで示した地点で、遠制ケーブル２を開放（遮断）して独立の検出区間を形成する。
ｃ．各検出区間の絶縁抵抗を測定し、障害点Ｆ１を含む区間を特定する。
ｄ．障害箇所を復旧した後、ｘ地点で遠制ケーブル２をそれぞれ接続する。
ｅ．通信が正常に行なわれることを確認する。
【０００６】
【発明が解決しようとする課題】
前述のような１対ｎ方式の遠制ケーブルでは、ケーブルが樹枝状に分岐しており、また障害地点の特定のために分割形成した検出区間には分岐点が含まれないようにしなければならないので、障害地点特定のためには多くの要員と長時間を要するのみならず、長い経験と熟練を必要とするという問題があった。また、開放したケーブルを、障害復旧後に再接続する際に誤接続や接続不良を生ずる恐れもあった。
【０００７】
さらに、障害が間欠的に発生するような場合には、障害地点の特定が事実上不可能と言えるほど困難であり、また長時間を要するために、迅速な障害復旧ができないという問題があった。
【０００８】
本発明の第１の目的は、障害地点の特定に際して遠制ケーブルの開放、切離し、再接続が不要であり、しかも間欠的障害地点も容易に探査・標定できる遠制ケーブル障害点探査・標定方法および装置を提供することにある。
【０００９】
本発明の他の目的は、検出された遠制ケーブルの障害が間欠的、不規則である場合にも確実かつ可及的迅速に障害点を標定でき、遠制ケーブルの張り替え量の最少化と事故復旧の迅速化とを両立させることのできる遠制ケーブルの障害点標定方法および装置を提供することにある。
【００１０】
【課題を解決するための手段】
前記目的を達成するために、本発明は、既知特性の監視信号を生成する発信回路、および前記監視信号を、配電線に対応して、親局と複数の子局とを接続するように敷設され、当該配電系統の監視および制御を行なうための有線式配電線遠方監視制御用通信ケーブルの親局以外の任意箇所に結合させて注入する結合手段を具備した監視信号注入装置と、前記ケーブルに結合してその電流および電圧、ならびにデ−タエラーの少なくとも一つを検出するための結合手段、検出された前記電流および電圧の少なくとも一方から、前記監視信号の電流および電圧成分の少なくとも一方を抽出するフィルタ手段、前記監視信号の注入地点において予測される前記監視信号の電圧、電流の少なくとも一方の基準値を記憶する手段、および抽出された前記監視信号の電圧、電流の少なくとも一方の大きさを、前記基準値と比較し、比較結果にしたがって、前記通信ケーブルの障害箇所が、監視信号検出地点を起点として前記信号注入地点の側にあるか否かを判定する処理回路を含む検出装置との組合わせを具備する。
【００１１】
さらに本発明の前記検出装置は、抽出された監視信号の電圧、電流の大きさ、および前記通信ケーブルの障害箇所が、監視信号検出地点を起点として前記信号注入地点の側にあるか否かの判定結果の少なくとも１つを、予定時間の間記憶するメモリをさらに有することができる。
【００１２】
本発明においては、配電線に対応して、親局と複数の子局とを接続するように敷設され、当該配電系統の監視および制御を行なうための有線式配電線遠方監視制御用通信ケーブルの親局以外の任意箇所から既知周波数の監視信号を注入し、前記通信ケーブルの別の箇所で前記監視信号を検出し、検出された監視信号の電圧、電流の少なくとも一方の大きさを、例えば、前記監視信号の注入箇所から親局側をみたインピーダンスおよび負荷側をみたインピーダンスに基づいて予測される電圧、電流基準値と比較し、比較結果にしたがって、前記通信ケーブルの障害箇所が、監視信号検出地点を起点として前記信号注入地点の側にあるか否かを判定する。また必要に応じては、前記別の箇所でデ−タエラー０を検出し、エラーの有無をも勘案して障害方向を判別する。さらにこれらの検出デ−タを記憶し、障害発生の状態（頻度、時間、回数など）に基づいて間欠的に発生する障害を検知することもできる。
【００１３】
また本発明は、配電線に対応して、親局と複数の子局とを接続するように敷設され、当該配電系統の監視および制御を行なうための有線式配電線遠方監視制御用通信ケーブルの障害点標定のために、前記通信ケーブルの親局以外の任意箇所から既知特性の監視信号を注入し、前記通信ケーブルの別の箇所で、前記監視信号を検出する段階と、検出された監視信号の電圧、電流の少なくとも一方の大きさを、前記監視信号の検出箇所において予測される電圧、電流基準値と比較する段階と、前記比較の結果にしたがって、前記通信ケーブルの障害箇所が、監視信号検出地点を起点として前記信号注入地点の側にあるか否かを判定し、これに基づいて障害箇所を予定の距離範囲内に絞り込む段階と、その後さらに、前記監視信号の注入および検出を行ない、前記障害の検出を示す出力信号に応答して、前記通信ケーブル上の予定のパルス信号送信位置から前記絞り込まれた予定距離範囲に向けてパルス信号を送信し、パルスレーダ方式にしたがってパルス信号送信位置から前記障害箇所までの距離を測定し、障害点の位置を標定する段階とを具備した方法に特徴がある。
【００１４】
本発明はさらに、既知特性の監視信号を生成する発信回路、および前記監視信号を、配電線に対応して、親局と複数の子局とを接続するように敷設され、当該配電系統の監視および制御を行なうための有線式配電線遠方監視制御用通信ケーブルの親局以外の任意箇所に結合させて注入する結合手段を具備した監視信号注入装置と、前記ケーブルに結合してその電流および電圧の少なくとも一方を検出するための結合手段、検出された前記電流および電圧の少なくとも一方から、前記監視信号の電流および電圧成分の少なくとも一方を抽出するフィルタ手段、前記監視信号の検出箇所において予測される前記監視信号の電圧、電流の少なくとも一方の基準値を記憶する手段、および抽出された前記監視信号の電圧、電流の少なくとも一方の大きさを、前記基準値と比較し、比較結果にしたがって、前記通信ケーブルの障害箇所が、監視信号検出地点を起点として前記信号注入地点の側にあるか否かを判定する処理回路を具備した障害検出装置と、パルス信号を前記通信ケーブルに注入するパルス発信回路、前記通信ケーブル上のパルス信号を取り込むフィルタ回路、注入されたパルス信号からの取り込まれたパルス信号の遅延時間に基づいて障害点までの距離を標定する処理演算回路を具備し、前記障害検出装置からの障害検出に応答して起動されるパルスレーダ方式障害点標定装置との組合わせよりなる前記通信ケーブルの障害点標定装置に特徴がある。
【００１５】
【発明の実施の形態】
図１および図２を参照して本発明の１実施例を詳細に説明する。図１は本発明の１実施例の概要を示すブロック図、図２は監視信号注入装置（以下、「注入装置」と略する）および障害点検出装置（以下、「検出装置」と略する）の具体的構成例を示すブロック図である。これらの図において、図５と同一の符号は同一または同等部分を表わす。
【００１６】
遠制ケーブル２に障害を生じたことが、子局５との通信状態やそこからの返信状態などに基づいて判定された場合は、障害発生箇所と想定される地点の近傍に、遠制ケーブル２に特定の監視信号を重畳する注入装置８および前記監視信号を受信するための検出装置９を、図１、２に示すように取り付ける。この場合、注入装置８は検出装置９よりも親局１側に配置するのが好ましい。その理由は、一般に親局は低インピーダンスであるために、親局側では監視信号の漏れ電流が生じ易く、注入装置よりも親局側に検出装置を配置すると、上記漏れ電流を検出して誤動作し易いからである。
【００１７】
しかしながら、状況によっては、検出装置を注入装置よりも親局側に配置してもよいことは明らかである。また図示の例では、遠制ケーブルは上り回線２Ｕと下り回線２Ｄを別個に敷設した２対４線式であるから、予定の位相差を有する２種の監視信号をそれぞれの回線に各別に注入する。
【００１８】
注入装置８は、図２に詳細を示すように、予定特性（周波数）の監視信号を発生する発信回路１８、前記監視信号を供給されて位相の異なる２種の信号を生成する位相変調回路１７、これらの信号を増幅する増幅回路１６、および前記信号を遠制ケーブル２Ｕ、２Ｄにそれぞれ結合するＰＴ（電圧変成器）１４よりなり、同一周波数で予定の位相差を有する２種の監視信号を上り回線２Ｕ、および下り回線２Ｄ上にそれぞれ送出し、親局１と各子局５間で送受される遠制（遠隔制御）信号に重畳させる。なお１５は、遠制ケーブル２に生ずる雷サージなどを吸収して装置を保護する保安回路、１９は電源回路である。
【００１９】
検出装置９では、ＣＴ（電流変成器）２１およびＰＴ２２、ならびに保安回路２３を介して遠制ケーブル２上の信号が取り込まれ、さらに増幅回路２４で増幅された後、フィルタ回路２５によって監視信号および遠制信号が分離、抽出される。これら２つの信号はＡＤ変換回路２６でデジタル化された後、処理回路２７に転送される。ある特定の通信ポットから親局側および反対側（本明細書では「負荷側」という）をみたインピーダンス、および注入される監視信号の基準電圧は既知である。
【００２０】
また前記通信ポットに注入装置が取り付けられた場合に、そこから親局側および負荷側へ伝送される監視信号の漏れ電流も演算できるので、これらの各値を基準値として、他の通信ポットで検出された電流、電圧値を対比すれば、前記検出装置が取り付けられた他の通信ポットが注入装置８を基準として親局側にあるか負荷側にあるかを判別することができる。なお、各通信ポットや他の検出地点における電圧・電流基準は、実測などの適宜の手法によって予め収集しておくこともできる。
【００２１】
例えば図１のように、通信ポット３ｂに注入装置８を取り付け、通信ポット３ｃに検出装置９を取り付けた場合に、検出された電圧、電流値からは故障地点が負荷側（すなわち、注入装置とは反対側）と判定され、次に検出装置９を通信ポット３ｄに移動した場合に、故障地点が親局１側と判定されれば、故障地点Ｆ１は図示のように通信ポット３ｃおよび３ｄの間にあると決定することができる。
【００２２】
実際の配電線系統では、図３に示すように、親局１を起点とする遠制ケーブル２は樹枝状に複雑に分岐され、その延長距離は数Ｋｍ〜１０数Ｋｍにも及び、同図において、丸印で表わしている通信ポット数は数百またはそれ以上に達することがある。いま通信ポットＤ、Ｅ間の地点Ｆ１に障害が発生し、点線で囲んだ地域１０に異常が発生したことが判定できたと仮定し、障害地点よりも親局側の通信ポットＡに注入装置８を取り付けて監視信号を注入すると共に、通信ポットＢ、Ｃの２点に検出装置９を取り付けたと仮定する。
【００２３】
以上の説明から容易に理解できるように、Ｂ点の検出デ−タからは「障害地点は負荷側」と判定され、Ｃ点の検出デ−タからは「障害地点は注入装置側」と判定されるので、「障害地点はＢ点よりも負荷側」と決定することができる。つぎに、Ｃ点の検出装置を通信ポットＥに移動して測定を繰り返すと、Ｅ点の検出デ−タからは「障害地点は注入装置側」となるので、「障害地点はＢ点とＥ点の間」と最小の検出区間を決定することができる。このようにすれば、従来技術のように、遠制ケーブルを開放して検出区間を生成し、各検出区間について絶縁抵抗を測定する場合に比べて、障害点検出作業が格段に簡略化されることが分かる。また同時に使用する検出装置の個数は、前述の例に限らず、１以上の任意の個数に設定できる。
【００２４】
以上のようにして判別された障害点の方向情報は、対応の通信ポット情報、検出された電圧、電流値や、デ−タエラーの有無、障害発生時刻、回数などと共にメモリ３０に蓄積し、また（液晶）表示器２８およびターゲット表示器２９に表示することができる。ターゲット表示器２９は障害点の方向判定、検出が完了したことや判定結果を表示するものであり、特に、検出装置が電柱の上などに取付けられたときでも、前記の表示を地上から容易に識別できるような大きさと明瞭度で表示部が構成されるのが望ましい。このような情報を連続して予定時間蓄積し、総合判断すれば、特にその発生回数や頻度に基づいて、間欠的にしか発生せず、従来技術では検出が極めて難しかった障害も検出、確認することができる。
【００２５】
図４は各種障害の場合の本発明の検出動作を、さらに具体的に説明するための概念図である。この図において、前述のようにある程度絞り込まれた障害地点よりも親局１側の遠制ケーブル２の通信ポットには注入装置８を取り付け、下り回線２Ｄおよび上り回線２Ｕのそれぞれに、予定の位相差を有する監視信号ＳＧ１、ＳＧ２を注入する。一方注入装置８よりも負荷側であって、前記障害地点を挟む２つの相異なる通信ポットには検出装置９ａ、９ｂをそれぞれ取り付けて下り回線の電圧Ｖ１ａ、Ｖ１ｂおよび電流Ａ１ａ、Ａ２ａ、Ａ１ｂ、Ａ２ｂ、ならびに上り回線の電圧Ｖ２ａ、Ｖ２ｂおよび電流Ａ３ａ、Ａ４ａ、Ａ３ｂ、Ａ４ｂを測定する。この場合、２つの検出装置は別個のものを設置して同時に作動させても良いが、単一の検出装置を１つの設置位置から他の位置へ移動して測定しても良いことは勿論である。なお、注入装置を前記の位置に取り付ければ、障害地点の判定を効率よく行なうことができるので好ましいが、他の任意の位置に取り付けても障害地点の判定を行なうことは可能である。
【００２６】
障害がなく、正常ならば、以上の説明から明らかなように、２つの位置で検出される監視信号の前記電圧Ｖ１ａ、Ｖ１ｂ、Ｖ２ａ、Ｖ２ｂはすべて基準値以上であり、一方その電流Ａ１ａ、Ａ２ａ、Ａ１ｂ、Ａ２ｂ、Ａ３ａ、Ａ４ａ、Ａ３ｂ、Ａ４ｂはすべて基準値以下（基準範囲内）である。ここで「基準値」は、前述のように、注入装置８が取り付けられた通信ポットからみた親局側および負荷側のインピーダンスおよび監視信号の電圧に基づいて、検出装置の各設置位置に対して予め演算できる値、または実測によって得られる値に基づいて決められるものである。
【００２７】
図４において、ｘ印で示す断線障害Ｆ４の場合は、障害地点よりも親局側の検出装置９ａでは「正常」な検出値Ｖ１ａ、Ｖ２ａが得られるが、負荷側の検出装置９ｂでは電圧Ｖ１ｂ、Ｖ２ｂが基準値以下となる。また電流Ａ１ａ、Ａ２ａ、Ａ１ｂ、Ａ２ｂ、Ａ３ａ、Ａ４ａ、Ａ３ｂ、Ａ４ｂはすべてほぼ零である。したがって、これらの検出値に基づいて２つの検出装置９ａ、９ｂ間で断線事故を生じていると判定できる。
【００２８】
Ｆ５で示す地絡障害の場合は、検出電圧Ｖ１ａ、Ｖ１ｂが基準値以下、電流Ａ１ａが基準値以上、電流Ａ１ｂが基準値以下であり、さらに負荷側の検出装置９ｂでは遠制信号のデータエラーが検出されることが多い。これらの情報に基づいて２つの検出装置９ａ、９ｂ間の地絡事故を判別できる。
【００２９】
Ｆ６で示す短絡障害の場合は、検出装置９ａでは電圧Ｖ１ａが基準値以下、電流Ａ１ａおよびＡ２ａが基準値以上となる。また検出装置９ｂでは電圧Ｖ１ｂが基準値以下、電流Ａ１ｂおよびＡ２ｂも基準値以下となる。
【００３０】
Ｆ７で示すような混触障害（１つの信号線対から他の信号線対に跨がるような短絡）の場合は、検出装置９ａで測定した電流Ａ１ａ，Ａ３ａが基準値以上となることに基づいて障害検出が可能である。また検出装置９ｂにおいては、遠制信号のデータエラーが検出される。これにより、２つの検出装置９ａ、９ｂ間における２つの信号線対２Ｄ、２Ｕ間の混触事故を判別できる。なおこの場合、上り回線２Ｕと下り回線２Ｄに注入される監視信号の周波数は等しくされているので、両回線に注入された監視信号が同位相であると、混触箇所には監視電流が流れず、混触検出ができなくなる。したがって、この場合は、２つの回線２Ｕ、２Ｄに注入される監視信号は、両方の監視電流の位相差が、両者間に検出可能な電流が流れる程度に大きくなければならない。
【００３１】
なお以上では、注入装置及び検出装置は通信ポットに取り付けるものとしたが、原理的には遠制ケーブルのどこに取り付けても同様の障害検知ができることは明らかである。また注入する監視信号は、波形、周波数、変調形式などの特性の面で遠制信号と区別できるものであれば、どのようなものでもよい。
【００３２】
以上のようにして、障害区間を最小（すなわち、隣接する２つの）通信ポット間にまで絞り込んだ後に、その間の遠制ケーブルを張り替えて障害点を復旧する。その後、通信状態が正常に復帰したことを確認する。
【００３３】
上述の実施例によれば、遠制ケーブルを開放したり再接続したりすることなしに、障害箇所を短時間で、容易に、かつ特別の経験や熟練を要せずに検出区間単位で特定することができるので、障害発生から復旧までの時間を大幅に短縮でき、さらにそのための要員数を減らすことができる。また動作状態での連続監視ができるので、従来は事実上不可能であった間欠性の障害の検出もできるようになる。
【００３４】
しかしながら、障害点復旧のための遠制ケーブル張り替えを、上記のように、最小の隣接通信ポット間で行なうと、張り替える遠制ケーブルの量が多く、その区間内で正常なケーブル部分も捨てることになることから、資源の無駄が生じるのみならず、張り替えの作業量や時間も多くなってコストも高くなるという問題がある。
【００３５】
このような無駄なコストを削減するためには、前記最小通信ポット間内での障害点の位置をさらに可及的狭い区間または地点まで絞り込み、張替え区間を最短に抑えることが望ましい。障害点のより精細な標定手法としては、パルスレーダ方式が知られている。障害が永久的なものであるときは、前述のようにして障害点をより狭い区間または地点にまで絞り込んだ後に、前記最小通信ポット間の１方端のポットにパルスレーダ方式障害点標定装置を取り付けて手動操作で起動することにより、障害点位置の標定ができる。
【００３６】
しかし、障害が間欠的、不規則で、その発生タイミングが予測できないときは、上記のような手動操作による障害点位置標定は極めて困難であり、事実上不可能に近いので、障害点の標定に長時間を要し、事故復旧が遅れてしまうことになり易い。事故復旧の迅速化を優先するためには、最小通信ポット間での遠制ケーブル張り替えを行なわざるを得ないので、遠制ケーブルの張り替え量や作業量、コストの最少化と事故復旧の迅速化を両立させることが困難であるという問題があった。
【００３７】
本発明の第２実施例は、前述の問題を解決し、検出された遠制ケーブルの障害が間欠的、不規則である場合にも確実かつ可及的迅速に障害点を標定でき、遠制ケーブルの張り替え量の最少化と事故復旧の迅速化とを両立させることを可能にするものである。
【００３８】
以下に図面を参照して、本発明の第２実施例を詳細に説明する。後述の各図において、図１〜５と同一の符号は同一または同等部分を表わす。
【００３９】
図６は、本実施例に好適な監視信号注入装置８、障害点検出装置９およびパルスレーダ方式障害点標定装置４０の詳細ブロック図である。なお、当業者には自明なように、第１実施例に関して前述した障害箇所の絞り込みの段階では、パルスレーダ方式障害点標定装置（以下、「パルスレーダ装置」と略する）は必ずしも接続される必要はない。また図６では、障害点検出装置９が接続されている通信ポットに、パルスレーダ装置４０も共通に接続されるように示されているが、このことは必要では無く、別の箇所や障害点検出装置９と共通の通信ポットに接続されても良い。
【００４０】
第１実施例に関して前述したようにして隣接する２つの最小通信ポット間（以下、「障害区間」と略する）まで障害点Ｆ１の絞込みが行なわれた後、例えば図７に示すように、障害点検出装置９が接続されたポットにパルスレーダ装置４０を接続する。そしてパルスレーダ装置から、パルス信号を注入して障害点からの反射信号を受信し、その遅れ時間を計測すれば、既知の手法により、パルスレーダ装置４０から障害点Ｆ１までの距離を演算することができる。その際、障害区間の外側からの反射信号を遮断するために、パルス信号注入点の障害区間とは反対側の遠制ケーブル２の各線にブロッキングコイル４を直列に接続するのが望ましい。
【００４１】
図８は、通信ポット３内で、ブロッキングコイル４を直列に挿入したり、取り外したりする手法を説明するための図である。直列挿入のためには、初めにブロッキングコイル４を通信線に並列に接続した後、×印の点で通信線を開放すればよい。また前記コイルを取り除くときは、×印の点の通信線２を接続した後で、前記コイルを外せば良い。
【００４２】
障害が恒久的であるときは、上述のようにパルスレーダ装置を接続して手動で起動させ、通信線２Ｕ、２Ｄに単パルスを注入してその反射パルスを検出すれば障害点の標定ができる。しかし、障害が間欠的であると、その障害の発生が不規則で、発生タイミングの予測も困難であるから、パルスレーダ装置を手動で起動させる方法による障害点標定は極めて困難であり、事実上不可能に近い。これに対処するために、本実施例では、障害検出を示す障害点検出装置９からの出力信号でパルスレーダ装置４０からのパルス送信を自動的にトリガし、障害点標定動作を開始させ、得られた結果（障害点までの距離および／または送信パルスに対する反射パルス受信の遅れ時間）をメモリに記憶する。
【００４３】
以下に、図６、９を参照して本実施例の要点をさらに詳細に説明する。図６は、隣接する２つの通信ポット間にまで障害点を絞り込んだ後における、監視信号注入装置８と障害点検出装置９、パルスレーダ装置４０およびブロッキングコイル４の配置例を示すブロック図であり、図９は前記パルス送信を起動するトリガ信号および送出されるパルス信号を示す。
【００４４】
図６において、パルスレーダ装置４０は、障害点検出装置９が間欠的障害を検出したことを示す出力信号を外部トリガ信号として受信する。これに応答して、パルス発信回路３４は、予め設定された電圧・幅のパルス信号を生成し、結合トランス３３を介して、遠制ケーブル２に注入する。
【００４５】
それと同時に、遠制ケーブル２から取り込まれた信号がフィルタ回路３５に供給され、そこで遠制信号が取り除かれ、送信パルス信号と遠制ケーブル２の障害点Ｆ１からの反射パルス信号だけがＡ／Ｄ変換回路３６でデジタル化され、その信号波形データがメモリカード（一般的には、メモリ）３８に一時保存される。信号測定完了後に保存された信号波形データから、またはリアルタイムで、処理回路３７に搭載されているＣＰＵを用いて遅延時間を演算し、さらに通信線上の既知のパルス伝搬速度を用いて距離変換を行なうことができる。
【００４６】
さらに、前記信号波形データを（液晶タッチパネル）表示器３９に出力し、その測定波形から障害点の位置標定を行なうこともできる。これら装置の動作電源は直流電源でも交流電源でも適宜に選択できる。また直流電源（バッテリ）でなるべく長期間測定できるように、前記電源回路の投入を外部トリガ信号によって制御し、常時は前記電源がオフに保持されるようにすることもできる。
【００４７】
図９は、通信線に注入されるパルス信号の１例を示すタイムチャートである。遠制ケーブル２の各線間に、障害点検出装置９からの障害検出出力信号に応答して自動的にパルス信号を注入し、障害点からの反射信号が受信されるまでの時間遅れを測定すれば、既知の演算式にしたがって障害点の位置を標定できる。しかし、間欠的障害が発生する時刻や間隔はランダムであるために、単一のパルスを注入する場合は、注入の瞬間にたまたま間欠障害が発生していなければ、障害点からの反射信号が得られず、障害点の標定ができないことになる。
【００４８】
この対策として、本実施例では、各線間に単パルス信号または複数個（図の例では、３個）の連続パルス信号を注入する。こうすれば、間欠障害発生地点を高い確率で標定することができる。なお、消費電力量の節減のためには、連続パルスの個数は少なくした方が望ましい。また各回線へのパルス注入は、上り回線２Ｕおよび下り回線２Ｄに交互に行なうのが望ましい。このように、パルス信号を交互に注入すれば、同相での混触障害の時、上り・下り両回線にパルスを同タイミングで注入した場合に、混触障害点で対をなす相手通信線から流入してくるパルス信号と互いに打ち消し合って、反射信号が得られなくなり、このために、位置の標定が不可能になるという不都合が解消される。
【００４９】
上述のように、どちらか一方の回線のみにパルス信号を注入して、両回線の反射信号を測定した後に、残りの回線にパルス信号を注入して、両回線の反射信号を測定すれば、混触点からの反射信号を確実に捕捉することができ、障害位置の標定が可能となる。
【００５０】
図１０は、障害点検出装置９およびパルスレーダ装置４０を監視信号注入装置８と障害点Ｆ１との間に接続した例であり、障害が地絡または混触であって、特に通信線の電流を監視して障害を検知する場合に有効である。なお図７の接続は障害が断線または短絡であって、通信線の電圧を監視して障害を検知する場合に有効である。
【００５１】
本発明者らの実験によれば、注入するパルスの幅の選定が距離標定の精度に影響することが分かった。パルス幅が広いと、障害点からの反射レベルが大きく計測可能距離は伸びるが、一方、パルス幅内に位置する障害点からの反射波形は認識できないために、計測不能領域が広がる欠点がある。すなわち、距離測定精度を上げるためにはパルス幅は狭いほうが望ましいが、障害点までの距離が長いときは、測定精度を犠牲にしてもパルス幅を広くして測定範囲を伸ばさなければならない。実験では、隣接通信ポット間の距離が４００ｍ以下のときはパルス幅を３０ｎ秒、距離が４００〜８００ｍのときはパルス幅を７０ｎ秒、８００〜１２００ｍのときはパルス幅を５００ｎ秒に設定したとき、好ましい結果が得られた。
【００５２】
以上では、パルスレーダ装置４０は障害点検出装置９と同じ通信ポットに接続されるものとした。このように接続すれば、障害検出を示す信号をトリガ信号として容易にパルスレーダ装置に供給することができる点で有利である。しかし、本発明はこれに限定されるものではなく、前記障害検出信号をトリガ信号として供給する手段（例えば、無線通信手段）を準備すれば、他の適当な任意の箇所にパルスレーダ装置４０を接続できることは当然である。
【００５３】
以上の説明から明らかなように、第２実施例によれば、検出された遠制ケーブルの障害が永久的であるときはもちろん、間欠的、不規則である場合にも正確かつ可及的迅速に障害点を標定でき、遠制ケーブルの張り替え量の最少化と事故復旧の迅速化とを両立させることができる。
【００５４】
【発明の効果】
本発明によれば、遠制ケーブルを開放したり再接続したりすることなしに、障害箇所を短時間で、容易に、かつ特別の経験や熟練を要せずに検出区間単位で特定することができるので、障害発生から復旧までの時間を大幅に短縮でき、さらにそのための要員数を減らすことができる。また動作状態での連続監視ができるので、従来は事実上不可能であった間欠性の障害の検出もできるようになる。
【００５５】
また検出された遠制ケーブルの障害が永久的であるときはもちろん、間欠的、不規則である場合にも正確かつ可及的迅速に障害点を標定でき、遠制ケーブルの張り替え量の最少化と事故復旧の迅速化とを両立させることができる。
【図面の簡単な説明】
【図１】本発明の１実施例の概要を示すブロック図である。
【図２】図１に示した監視信号注入装置および障害点検出装置の詳細を示すブロック図である。
【図３】実際の配電線系統に本発明を適用した場合の動作を説明するための概念図である。
【図４】各種障害の場合の本発明の検出動作を説明するための概念図である。
【図５】従来の代表的な有線式配電線遠方監視制御系統の１例を示す概略図である。
【図６】本発明の第２実施例に好適な監視信号注入装置、障害点検出装置およびパルスレーダ方式障害点標定装置の詳細ブロック図である。
【図７】本発明の第２実施例を示す概略ブロック図である。
【図８】ブロッキングコイルの接続、取り外しを説明するための回路図である。
【図９】パルスレーダ方式障害点標定装置の外部トリガ信号および注入パルスの１例を示す波形図である。
【図１０】本発明のさらに他の実施態様を示す概略ブロック図である。
【符号の説明】
１は配電線遠方監視制御親局装置、２は遠制ケーブル、３、３ａ〜３ｄは通信ポット、４はブロッキングコイル、５は配電線遠方監視制御子局装置、６は高圧開閉器、７は高圧配電線、８は監視信号注入装置、９は障害点検出装置、１７は位相変調回路、１８は発信回路、２７は処理回路、４０はパルスレーダ方式障害点標定装置である。[0001]
BACKGROUND OF THE INVENTION
The present invention is laid so as to connect a master station normally installed at a sales office of a distribution system and a plurality of slave stations installed at appropriate locations corresponding to the distribution lines, and performs remote monitoring and control of the distribution system. In particular, the present invention relates to a method and an apparatus for investigating a fault point in a communication cable for remote monitoring and control of a wired distribution line, and particularly to a ground fault occurring in a communication cable for remote monitoring and control used as a communication medium between a master station and a plurality of slave stations. The present invention relates to a method and an apparatus for exploring occurrence points of various faults such as short circuit, incompatibility and disconnection.
[0002]
The present invention also relates to a method and apparatus for more precisely locating a failure occurrence position when the occurrence of various failures as described above is detected in the communication cable, particularly when the failure is intermittent. Further, the present invention relates to a failure occurrence position locating method and apparatus that can reliably locate a failure occurrence position.
[0003]
[Prior art]
A communication cable is laid to connect the master station installed at the sales office of the distribution system and a plurality of slave stations installed at appropriate locations on the distribution line in a one-to-n system, and various control signals and Information is exchanged to monitor and control the distribution system.
[0004]
FIG. 5 is a schematic diagram showing an example of a conventional typical wired distribution line remote monitoring control system. Two-to-four-wire remote monitoring control with the master station 1 installed in the sales office of the power distribution system and a plurality of slave stations 5 installed at appropriate locations on the distribution line (for example, a maximum of about 230 stations per master station) The communication cable (hereinafter abbreviated as “distance cable”) 2 is connected in a one-to-n system. Communication pots 3a, 3b, 3c... Are provided at appropriate positions of the distance control cable 2, and a distance control cable to the slave station 5 is branched therefrom. Each slave station 5 is provided corresponding to the high voltage switch 6 installed in the distribution line 7, and controls the opening and closing of the switch 6 according to a control signal transmitted from the master station via the distance control cable 2, The open / close state is monitored and necessary information is transmitted to the master station 1. In this way, the master station 1, that is, the sales office, can always grasp the state of each slave station 5 and high-voltage switch 6 under its jurisdiction.
[0005]
If a failure occurs in the distance control cable 2 at the location F1, the failure location is identified by the following procedure, for example.
a. Based on the response status from the slave station 5, the failure location is roughly narrowed down.
b. At a point indicated by x marks 2a to 2d in the narrowed-down area, the distance control cable 2 is opened (blocked) to form an independent detection section.
c. The insulation resistance of each detection section is measured, and the section including the failure point F1 is specified.
d. After recovering from the fault location, the distance control cable 2 is connected at the point x.
e. Check that communication is performed normally.
[0006]
[Problems to be solved by the invention]
In the one-to-n distance control cable as described above, the cable is branched in a dendritic manner, and the branching point must not be included in the detection section divided to identify the failure point. Therefore, there is a problem that not only a lot of personnel and a long time are required for identifying the failure point, but also a long experience and skill are required. In addition, there is a risk of erroneous connection or connection failure when the opened cable is reconnected after failure recovery.
[0007]
Furthermore, when a failure occurs intermittently, it is difficult to identify the point of failure, and it takes a long time, so there is a problem that the failure cannot be recovered quickly. .
[0008]
A first object of the present invention is to detect and locate a faulty cable fault point that does not require the opening, disconnecting, and reconnection of the distance control cable when specifying the faulty point, and can easily search and pinpoint intermittent faulty points. And providing an apparatus.
[0009]
Another object of the present invention is that even if the detected fault of the distance control cable is intermittent or irregular, it is possible to locate the fault point reliably and as quickly as possible, minimizing the amount of replacement of the distance control cable. An object of the present invention is to provide a fault location method and apparatus for a distance control cable that can achieve both speed of accident recovery.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a transmission circuit that generates a monitoring signal having a known characteristic, and the monitoring signal is laid so as to connect a master station and a plurality of slave stations corresponding to a distribution line. Of the communication cable for remote monitoring and control of the wired distribution line for monitoring and controlling the distribution system. Other than the master station A monitoring signal injection device comprising coupling means for coupling and injecting at an arbitrary location; coupling means for coupling to the cable and detecting at least one of its current and voltage, and data error; Filter means for extracting at least one of the current and voltage component of the monitoring signal from at least one of current and voltage, and storing at least one reference value of the voltage and current of the monitoring signal predicted at the injection point of the monitoring signal Comparing the at least one of the extracted voltage and current of the monitoring signal with the reference value, and according to the comparison result, the failure point of the communication cable starts from the monitoring signal detection point. A combination with a detection device including a processing circuit for determining whether or not it is on the signal injection point side is provided.
[0011]
Further, the detection device of the present invention is configured to determine whether the voltage of the extracted monitoring signal, the magnitude of the current, and the failure location of the communication cable are on the signal injection point side starting from the monitoring signal detection point. A memory for storing at least one of the determination results for the scheduled time may be further included.
[0012]
In the present invention, a wired distribution line remote monitoring control communication cable is installed to connect a master station and a plurality of slave stations corresponding to the distribution line, and to monitor and control the distribution system. Other than the master station A monitoring signal of a known frequency is injected from an arbitrary location, the monitoring signal is detected at another location of the communication cable, and the magnitude of at least one of the voltage and current of the detected monitoring signal is determined, for example, Compared with the voltage and current reference values that are predicted based on the impedance seen from the injection station on the master station side and the impedance seen on the load side, according to the comparison result, the failure location of the communication cable starts from the monitoring signal detection location It is determined whether it is on the signal injection point side. If necessary, a data error 0 is detected at the other location, and the failure direction is determined in consideration of the presence or absence of the error. Further, these detection data are stored, and a failure that occurs intermittently can be detected based on the state (frequency, time, number of times, etc.) of the failure occurrence.
[0013]
Further, the present invention provides a wired distribution line remote monitoring control communication cable that is laid so as to connect a master station and a plurality of slave stations corresponding to the distribution line, and performs monitoring and control of the distribution system. For fault location, the communication cable Other than the master station Injecting a monitoring signal having a known characteristic from an arbitrary location and detecting the monitoring signal at another location of the communication cable, and at least one of the voltage and current of the detected monitoring signal is determined as the monitoring signal. In accordance with the step of comparing with the voltage and current reference values predicted at the detection location of the detection point, whether or not the failure location of the communication cable is on the side of the signal injection location starting from the monitoring signal detection location A step of narrowing down a failure location within a predetermined distance range based on this, and then further injecting and detecting the monitoring signal, and in response to an output signal indicating the detection of the failure, the communication A pulse signal is transmitted from the planned pulse signal transmission position on the cable toward the narrowed planned distance range, and the pulse signal is transmitted from the pulse signal transmission position according to the pulse radar system. Measuring the distance to the fault location, it is characterized in the method comprising the the steps of locating the position of the point of failure.
[0014]
The present invention further provides a transmission circuit for generating a monitoring signal having a known characteristic, and the monitoring signal is laid so as to connect a master station and a plurality of slave stations corresponding to a distribution line, and monitors the distribution system. And cable for remote monitoring and control of wired distribution lines for control Other than the master station A monitoring signal injection device having coupling means for coupling and injecting at an arbitrary location, coupling means for coupling to the cable and detecting at least one of the current and voltage, and at least one of the detected current and voltage Filter means for extracting at least one of the current and voltage components of the monitoring signal, means for storing at least one reference value of the voltage and current of the monitoring signal predicted at the detection location of the monitoring signal, and The magnitude of at least one of the voltage and current of the monitoring signal is compared with the reference value, and according to the comparison result, the failure point of the communication cable is located on the signal injection point side starting from the monitoring signal detection point. Fault detection device having a processing circuit for determining whether or not there is a pulse transmission for injecting a pulse signal into the communication cable A path, a filter circuit for capturing a pulse signal on the communication cable, and a processing arithmetic circuit for locating a distance to the failure point based on a delay time of the captured pulse signal from the injected pulse signal, and detecting the failure The communication cable failure point locating device is characterized by a combination with a pulse radar type failure point locating device which is activated in response to a failure detection from the device.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described in detail with reference to FIGS. FIG. 1 is a block diagram showing an outline of one embodiment of the present invention. FIG. 2 is a monitoring signal injection device (hereinafter abbreviated as “injection device”) and a fault point detection device (hereinafter abbreviated as “detection device”). It is a block diagram which shows the specific structural example of these. In these drawings, the same reference numerals as those in FIG. 5 represent the same or equivalent parts.
[0016]
When it is determined that a failure has occurred in the distance control cable 2 based on the communication status with the slave station 5 or the response status from the slave station 5, the distance control cable is located near the point where the failure is expected. An injection device 8 for superimposing a specific monitoring signal on 2 and a detection device 9 for receiving the monitoring signal are attached as shown in FIGS. In this case, it is preferable that the injection device 8 is disposed closer to the master station 1 than the detection device 9. The reason is that since the master station generally has a low impedance, a leakage current of the monitoring signal is likely to occur on the master station side, and if the detection device is placed closer to the master station side than the injection device, the leakage current is detected and malfunctions. This is because it is easy to do.
[0017]
However, it is obvious that the detection device may be arranged closer to the parent station side than the injection device depending on the situation. In the example shown in the figure, the distance control cable is a 2-to-4 wire system in which the upstream line 2U and the downstream line 2D are separately laid, so that two types of monitoring signals having a predetermined phase difference are injected into each line separately. To do.
[0018]
As shown in detail in FIG. 2, the injection device 8 includes a transmission circuit 18 that generates a monitoring signal of a predetermined characteristic (frequency), and a phase modulation circuit 17 that is supplied with the monitoring signal and generates two types of signals having different phases. , An amplifying circuit 16 for amplifying these signals, and a PT (voltage transformer) 14 for coupling the signals to the distance cables 2U and 2D, respectively, and two kinds of monitoring signals having a predetermined phase difference at the same frequency. The signals are transmitted on the uplink 2U and the downlink 2D, respectively, and superimposed on a remote control (remote control) signal transmitted / received between the master station 1 and each slave station 5. Reference numeral 15 is a safety circuit that protects the device by absorbing lightning surges and the like generated in the distance control cable 2, and 19 is a power supply circuit.
[0019]
In the detection device 9, the signal on the distance control cable 2 is taken in via the CT (current transformer) 21 and PT 22 and the safety circuit 23, further amplified by the amplifier circuit 24, and then monitored by the filter circuit 25. Distance control signals are separated and extracted. These two signals are digitized by the AD conversion circuit 26 and then transferred to the processing circuit 27. The impedance of the base station side and the opposite side (referred to herein as “load side”) from a specific communication pot, and the reference voltage of the monitoring signal to be injected are known.
[0020]
In addition, when an injection device is attached to the communication pot, the leakage current of the monitoring signal transmitted from the master station side to the load side can also be calculated, so these values can be used as reference values in other communication pots. By comparing the detected current and voltage values, it is possible to determine whether another communication pot to which the detection device is attached is on the master station side or the load side with reference to the injection device 8. The voltage / current reference at each communication pot and other detection points can be collected in advance by an appropriate method such as actual measurement.
[0021]
For example, as shown in FIG. 1, when the injection device 8 is attached to the communication pot 3b and the detection device 9 is attached to the communication pot 3c, the detected voltage and current values indicate that the failure point is on the load side (ie, the injection device and If the failure point is determined to be the master station 1 side when the detection device 9 is moved to the communication pot 3d and then the failure point F1 is determined to be the communication pots 3c and 3d as shown in the figure. Can be determined to be in between.
[0022]
In the actual distribution line system, as shown in FIG. 3, the distance control cable 2 starting from the master station 1 is complicatedly branched in a dendritic shape, and the extension distance ranges from several kilometers to several kilometers. The number of communication pots represented by circles may reach several hundred or more. It is assumed that a failure has occurred at the point F1 between the communication pots D and E, and it has been determined that an abnormality has occurred in the area 10 surrounded by the dotted line. It is assumed that a monitoring signal is injected and a detection device 9 is attached to two points of communication pots B and C.
[0023]
As can be easily understood from the above description, “the failure point is the load side” is determined from the detection data at point B, and “the failure point is the injection device side” from the detection data at point C. Therefore, it can be determined that “the failure point is on the load side than point B”. Next, when the detection device at point C is moved to the communication pot E and measurement is repeated, the failure point is the injection device side from the detection data at point E. Between the points "and the smallest detection interval can be determined. In this way, as in the prior art, the fault detection operation is greatly simplified compared to the case where the distance control cable is opened to generate the detection section and the insulation resistance is measured for each detection section. I understand that. The number of detection devices used at the same time is not limited to the above example, and can be set to an arbitrary number of 1 or more.
[0024]
The failure point direction information determined as described above is stored in the memory 30 together with the corresponding communication pot information, detected voltage, current value, presence / absence of data error, failure occurrence time, number of times, etc. It can be displayed on the (liquid crystal) display 28 and the target display 29. The target indicator 29 displays the direction determination and detection result of the obstacle point and the determination result. In particular, even when the detection device is mounted on a utility pole, the display can be easily performed from the ground. It is desirable that the display unit be configured with such a size and clarity that can be identified. If such information is continuously accumulated for a predetermined time and comprehensively judged, faults that occur only intermittently and are extremely difficult to detect with the prior art are detected and confirmed, especially based on the frequency and frequency of occurrence. be able to.
[0025]
FIG. 4 is a conceptual diagram for more specifically explaining the detection operation of the present invention in the case of various faults. In this figure, an injection device 8 is attached to the communication pot of the distance control cable 2 on the master station 1 side from the failure point narrowed down to some extent as described above, and each of the downlink 2D and the uplink 2U has a predetermined position. Monitoring signals SG1 and SG2 having a phase difference are injected. On the other hand, detection devices 9a and 9b are attached to two different communication pots on the load side of the injection device 8 and sandwich the failure point, respectively, and downlink voltages V1a and V1b and currents A1a, A2a, A1b and A2b are attached. , And uplink voltages V2a, V2b and currents A3a, A4a, A3b, A4b. In this case, two detection devices may be installed separately and operated simultaneously, but it goes without saying that a single detection device may be moved from one installation position to another position for measurement. is there. Note that it is preferable to attach the injection device to the above position because it is possible to efficiently determine the failure point, but it is possible to determine the failure point even if it is attached to any other position.
[0026]
If there is no fault and it is normal, as is clear from the above description, the voltages V1a, V1b, V2a, V2b of the monitoring signals detected at the two positions are all equal to or higher than the reference value, while their currents A1a, A2a , A1b, A2b, A3a, A4a, A3b, A4b are all below the reference value (within the reference range). Here, as described above, the “reference value” is based on the impedance on the master station side and the load side seen from the communication pot to which the injection device 8 is attached and the voltage of the monitoring signal. It is determined based on a value that can be calculated in advance or a value obtained by actual measurement.
[0027]
In the case of the disconnection fault F4 indicated by x in FIG. 4, “normal” detection values V1a and V2a are obtained by the detection device 9a closer to the master station than the failure point, but the voltage V1b is obtained by the detection device 9b on the load side. , V2b is below the reference value. The currents A1a, A2a, A1b, A2b, A3a, A4a, A3b, and A4b are all substantially zero. Therefore, based on these detection values, it can be determined that a disconnection accident has occurred between the two detection devices 9a and 9b.
[0028]
In the case of the ground fault indicated by F5, the detection voltages V1a and V1b are not more than the reference value, the current A1a is not less than the reference value, the current A1b is not more than the reference value, and the load-side detection device 9b has a data error in the far distance signal. Is often detected. Based on these pieces of information, it is possible to determine a ground fault between the two detection devices 9a and 9b.
[0029]
In the case of the short-circuit fault indicated by F6, in the detection device 9a, the voltage V1a is equal to or lower than the reference value, and the currents A1a and A2a are equal to or higher than the reference value. In the detection device 9b, the voltage V1b is less than the reference value, and the currents A1b and A2b are also less than the reference value.
[0030]
In the case of an incompatibility failure as indicated by F7 (a short circuit extending from one signal line pair to another signal line pair), the currents A1a and A3a measured by the detection device 9a are based on the reference value or more. Fault detection. Further, in the detection device 9b, a data error of the distance control signal is detected. As a result, it is possible to discriminate a mixed accident between the two signal line pairs 2D and 2U between the two detection devices 9a and 9b. In this case, since the frequencies of the monitoring signals injected into the upstream line 2U and the downstream line 2D are equal, if the monitoring signals injected into both lines are in the same phase, the monitoring current does not flow in the contact area. Incompatible detection is not possible. Therefore, in this case, the monitoring signal injected into the two lines 2U and 2D must be so large that the phase difference between the two monitoring currents flows between them.
[0031]
In the above description, the injection device and the detection device are attached to the communication pot. However, in principle, it is obvious that the same failure can be detected regardless of where the distance control cable is attached. The monitoring signal to be injected may be any signal as long as it can be distinguished from the distance control signal in terms of characteristics such as the waveform, frequency, and modulation format.
[0032]
As described above, after the failure section is narrowed down to the minimum (that is, between two adjacent communication pots), the distance control cable between them is replaced to restore the failure point. Thereafter, it is confirmed that the communication state has returned to normal.
[0033]
According to the above-described embodiment, it is possible to easily identify a fault location in a short time without opening or reconnecting the distance control cable and without requiring special experience or skill. As a result, the time from failure occurrence to recovery can be greatly shortened, and the number of personnel for that purpose can be further reduced. In addition, since continuous monitoring can be performed in the operating state, it is possible to detect intermittent faults that were practically impossible in the past.
[0034]
However, if the replacement of the distance control cable for recovery from the failure point is performed between the minimum adjacent communication pots as described above, the amount of distance control cable to be replaced is large, and the normal cable portion is also discarded in the section. Therefore, there is a problem that not only resources are wasted, but also the amount of work and time for replacement are increased and the cost is increased.
[0035]
In order to reduce such a useless cost, it is desirable to narrow down the position of the failure point within the minimum communication pot to the narrowest possible section or point, and to minimize the replacement section. A pulse radar method is known as a finer method of locating the obstacle point. When the fault is permanent, after narrowing down the fault point to a narrower section or point as described above, a pulse radar type fault point locator is installed in the one end pot between the minimum communication pots. By attaching and starting it manually, the location of the obstacle point can be determined.
[0036]
However, when the failure is intermittent or irregular and the timing of its occurrence cannot be predicted, it is extremely difficult to determine the location of the failure point by manual operation as described above. It takes a long time, and accident recovery is likely to be delayed. In order to give priority to speeding up accident recovery, it is necessary to replace the distance control cable between the minimum communication pots. Therefore, the distance, work amount, and cost of the distance control cable replacement must be minimized and the accident recovery speeded up. There is a problem that it is difficult to achieve both.
[0037]
The second embodiment of the present invention solves the above-mentioned problem, and even when the detected fault of the distance control cable is intermittent or irregular, the fault point can be determined reliably and as quickly as possible. This makes it possible to achieve both minimizing the amount of cable replacement and speeding up accident recovery.
[0038]
Hereinafter, a second embodiment of the present invention will be described in detail with reference to the drawings. In each figure mentioned later, the same code | symbol as FIGS. 1-5 represents the same or equivalent part.
[0039]
FIG. 6 is a detailed block diagram of the monitoring signal injection device 8, the failure point detection device 9, and the pulse radar type failure point locating device 40 suitable for this embodiment. As is obvious to those skilled in the art, at the stage of narrowing down the fault location described above with respect to the first embodiment, a pulse radar type fault point locating device (hereinafter abbreviated as “pulse radar device”) is not necessarily connected. There is no need. In FIG. 6, the pulse radar device 40 is also commonly connected to the communication pot to which the failure point detection device 9 is connected. However, this is not necessary, and another location or failure inspection is possible. It may be connected to a communication pot common to the dispensing device 9.
[0040]
As described above with reference to the first embodiment, after the failure point F1 is narrowed down between two adjacent minimum communication pots (hereinafter referred to as “failure section”), the failure is performed as shown in FIG. The pulse radar device 40 is connected to the pot to which the point detection device 9 is connected. Then, if a pulse signal is injected from the pulse radar device, a reflection signal from the failure point is received, and the delay time is measured, the distance from the pulse radar device 40 to the failure point F1 is calculated by a known method. Can do. At that time, in order to block the reflected signal from the outside of the fault section, it is desirable to connect the blocking coil 4 in series to each line of the distance cable 2 on the opposite side of the fault signal injection point.
[0041]
FIG. 8 is a diagram for explaining a method of inserting or removing the blocking coil 4 in series in the communication pot 3. In order to insert in series, the blocking coil 4 is first connected in parallel to the communication line, and then the communication line is opened at the point marked with x. Further, when removing the coil, the coil may be removed after the communication line 2 at the point marked with x is connected.
[0042]
When the fault is permanent, the fault point can be determined by connecting the pulse radar device and starting it manually as described above, and injecting a single pulse into the communication lines 2U and 2D and detecting the reflected pulse. . However, if the fault is intermittent, the occurrence of the fault is irregular and it is difficult to predict the timing of the occurrence, so it is extremely difficult to determine the fault point by manually starting the pulse radar device. Nearly impossible. In order to cope with this, in the present embodiment, a pulse transmission from the pulse radar device 40 is automatically triggered by an output signal from the failure point detection device 9 indicating failure detection, and a failure point locating operation is started. The obtained result (distance to the fault point and / or delay time of reflection pulse reception with respect to the transmission pulse) is stored in the memory.
[0043]
Below, the main points of the present embodiment will be described in more detail with reference to FIGS. FIG. 6 is a block diagram illustrating an arrangement example of the monitoring signal injection device 8, the failure point detection device 9, the pulse radar device 40, and the blocking coil 4 after narrowing the failure point between two adjacent communication pots. FIG. 9 shows a trigger signal for starting the pulse transmission and a pulse signal to be transmitted.
[0044]
In FIG. 6, the pulse radar device 40 receives an output signal indicating that the failure point detection device 9 has detected an intermittent failure as an external trigger signal. In response to this, the pulse transmission circuit 34 generates a pulse signal having a preset voltage and width, and injects it into the distance control cable 2 via the coupling transformer 33.
[0045]
At the same time, the signal taken from the distance control cable 2 is supplied to the filter circuit 35, where the distance control signal is removed, and only the transmission pulse signal and the reflected pulse signal from the fault point F1 of the distance control cable 2 are A / D. The signal waveform data is digitized by the conversion circuit 36 and temporarily stored in a memory card (generally a memory) 38. The delay time is calculated from the signal waveform data stored after completion of the signal measurement or in real time using the CPU mounted on the processing circuit 37, and further distance conversion is performed using a known pulse propagation speed on the communication line. be able to.
[0046]
Further, the signal waveform data can be output to the (liquid crystal touch panel) display 39, and the location of the fault point can be determined from the measured waveform. The operating power supply of these devices can be appropriately selected from either a DC power supply or an AC power supply. Further, the power supply circuit can be turned on by an external trigger signal so that the DC power supply (battery) can be measured for as long as possible, and the power supply can be kept off at all times.
[0047]
FIG. 9 is a time chart showing an example of a pulse signal injected into the communication line. A pulse signal is automatically injected between each line of the distance control cable 2 in response to a failure detection output signal from the failure point detection device 9, and a time delay until a reflected signal from the failure point is received is measured. For example, the position of the obstacle point can be determined according to a known arithmetic expression. However, since the time and interval at which intermittent failures occur are random, when a single pulse is injected, a reflected signal from the point of failure is obtained unless an intermittent failure occurs by the moment of injection. The failure point cannot be located.
[0048]
As a countermeasure, in this embodiment, a single pulse signal or a plurality of (three in the example shown in the figure) continuous pulse signals are injected between the lines. In this way, the intermittent failure occurrence point can be determined with high probability. In order to save power consumption, it is desirable to reduce the number of continuous pulses. Further, it is desirable that pulse injection to each line is performed alternately on the uplink 2U and the downlink 2D. In this way, by alternately injecting pulse signals, in the event of incompatibility in the same phase, if the pulses are injected at the same timing on both the upstream and downstream lines, they will flow in from the partner communication line paired at the incompatibility point. By canceling each other with the incoming pulse signal, a reflected signal cannot be obtained, which eliminates the inconvenience that the position cannot be determined.
[0049]
As described above, after injecting a pulse signal only to one of the lines and measuring the reflected signal of both lines, injecting the pulse signal to the remaining line and measuring the reflected signal of both lines, The reflected signal from the contact point can be reliably captured, and the obstacle position can be determined.
[0050]
FIG. 10 is an example in which the failure point detection device 9 and the pulse radar device 40 are connected between the monitoring signal injection device 8 and the failure point F1, where the failure is a ground fault or incompatibility, and in particular the current of the communication line is This is effective when monitoring and detecting a failure. The connection shown in FIG. 7 is effective when the failure is a disconnection or a short circuit and the failure is detected by monitoring the voltage of the communication line.
[0051]
According to the experiments by the present inventors, it has been found that the selection of the width of a pulse to be injected affects the accuracy of distance measurement. When the pulse width is wide, the reflection level from the obstacle point is large and the measurable distance is extended. On the other hand, since the reflection waveform from the obstacle point located within the pulse width cannot be recognized, there is a disadvantage that the measurement impossible region is widened. That is, in order to increase the distance measurement accuracy, it is desirable that the pulse width is narrow. However, when the distance to the obstacle point is long, the pulse width must be widened to extend the measurement range even if the measurement accuracy is sacrificed. In the experiment, when the distance between adjacent communication pots is 400 m or less, the pulse width is set to 30 nsec, when the distance is 400 to 800 m, the pulse width is set to 70 nsec, and when the distance is set to 800 to 1200 m, the pulse width is set to 500 nsec. Favorable results were obtained.
[0052]
In the above, the pulse radar device 40 is connected to the same communication pot as the obstacle point detection device 9. This connection is advantageous in that a signal indicating failure detection can be easily supplied to the pulse radar device as a trigger signal. However, the present invention is not limited to this, and if a means for supplying the failure detection signal as a trigger signal (for example, a wireless communication means) is prepared, the pulse radar device 40 may be placed at any other appropriate location. Of course, you can connect.
[0053]
As is apparent from the above description, according to the second embodiment, the detected fault of the distance control cable is not only permanent, but also accurate and as quick as possible even when it is intermittent or irregular. The fault point can be located at the same time, and the amount of replacement of the distance control cable can be minimized and the accident can be recovered quickly.
[0054]
【The invention's effect】
According to the present invention, it is possible to identify a fault location in a short time, easily and without special experience or skill without opening or reconnecting the distance control cable. Therefore, the time from failure occurrence to recovery can be greatly shortened, and the number of personnel for that purpose can be reduced. In addition, since continuous monitoring can be performed in the operating state, it is possible to detect intermittent faults that were practically impossible in the past.
[0055]
In addition, it is possible to locate the fault point accurately and as quickly as possible even when the fault of the distance control cable is permanent, as well as when it is intermittent or irregular, minimizing the amount of replacement of the distance control cable. And speeding up accident recovery.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an outline of one embodiment of the present invention.
FIG. 2 is a block diagram showing details of a monitoring signal injection device and a failure point detection device shown in FIG. 1;
FIG. 3 is a conceptual diagram for explaining the operation when the present invention is applied to an actual distribution line system.
FIG. 4 is a conceptual diagram for explaining the detection operation of the present invention in the case of various faults.
FIG. 5 is a schematic diagram showing an example of a conventional typical wired distribution line remote monitoring control system.
FIG. 6 is a detailed block diagram of a monitoring signal injection device, a failure point detection device, and a pulse radar type failure point location device suitable for the second embodiment of the present invention.
FIG. 7 is a schematic block diagram showing a second embodiment of the present invention.
FIG. 8 is a circuit diagram for explaining connection and removal of a blocking coil.
FIG. 9 is a waveform diagram showing an example of an external trigger signal and an injection pulse of a pulse radar type fault location system.
FIG. 10 is a schematic block diagram showing still another embodiment of the present invention.
[Explanation of symbols]
1 is a distribution line remote monitoring control master station device, 2 is a remote control cable, 3 and 3a to 3d are communication pots, 4 is a blocking coil, 5 is a distribution line remote monitoring control slave station device, 6 is a high voltage switch, and 7 is A high-voltage distribution line, 8 is a monitoring signal injection device, 9 is a failure point detection device, 17 is a phase modulation circuit, 18 is a transmission circuit, 27 is a processing circuit, and 40 is a pulse radar type failure point locating device.

Claims

Corresponding to the distribution line, it is laid out to connect the master station and multiple slave stations, and it is a fault point search method for the communication cable for remote monitoring and control of the wired distribution line for monitoring and controlling the distribution system. There,
Injecting a monitoring signal of known characteristics from any location other than the master station of the communication cable;
Detecting the monitoring signal at another location other than the master station of the communication cable;
The magnitude of at least one of the voltage and current of the detected monitoring signal is compared with at least one of the voltage and current reference value predicted at the detection point of the monitoring signal, and the failure location of the communication cable is determined according to the comparison result. And a step of determining whether or not it is on the side of the signal injection point from the monitoring signal detection point as a starting point.

Further comprising detecting a data error of a remote monitoring control signal transmitted on the communication cable at a location other than the other master station of the communication cable,
In addition to the comparison result, the presence or absence of the data error is also taken into consideration, and it is determined whether or not the failure point of the communication cable is on the signal injection point side starting from the monitoring signal detection point. The fault point search method for the communication cable for remote monitoring and control of the wired distribution line according to claim 1.

Whether the detected monitoring signal voltage, current magnitude, remote monitoring control signal data error, and fault location of the communication cable are on the signal injection point side from the monitoring signal detection point Storing at least one of the determination results;
The wired system according to claim 2, wherein it is determined based on the stored data whether or not a failure location of the communication cable is on the signal injection point side with a monitoring signal detection point as a starting point. Fault point search method for communication cables for remote monitoring and control of distribution lines.

Corresponding to the distribution line, it is installed to connect the master station and multiple slave stations, and it is a fault location method for the communication cable for remote monitoring and control of the wired distribution line for monitoring and controlling the distribution system. There,
Injecting a monitoring signal of known characteristics from any location other than the master station of the communication cable, and detecting the monitoring signal at another location other than the master station of the communication cable;
Comparing the magnitude of at least one of the voltage and current of the detected monitoring signal with the voltage and current reference values expected at the detection location of the monitoring signal;
According to the result of the comparison, it is determined whether or not the failure point of the communication cable is on the signal injection point side starting from the monitoring signal detection point, and based on this, the failure point is within a predetermined distance range. The stage of narrowing down,
Thereafter, the monitoring signal is injected and detected, and in response to the output signal indicating the detection of the fault, a pulse signal is transmitted toward the narrowed planned distance range of the communication cable, and the pulse radar system is used. Therefore, the failure point locating method for the communication cable for remote monitoring and control of the wired distribution line, comprising the step of measuring the distance from the pulse signal transmission position to the failure point and locating the position of the failure point.

5. The fault location of a wired distribution line remote monitoring control communication cable according to claim 4, wherein the monitoring signal detection position and the scheduled pulse signal transmission position are substantially the same point on the communication cable. Method.

6. The blocking coil for blocking the passage of the pulse signal is connected in series to the communication cable opposite to the point of failure at the pulse signal transmission position during pulse signal transmission. A fault location method for communication cables for remote monitoring and control of wired distribution lines.

7. The fault location method for a wired distribution line remote monitoring control communication cable according to claim 6, wherein the blocking coil allows a normal communication signal to pass therethrough.

Transmission method of the said pulse signal is triggered by the output signal which shows the said fault detection, The fault point location method of the communication cable for wired distribution line remote monitoring control of Claim 4 thru | or 7 characterized by the above-mentioned.

The fault location method for a wired distribution line remote monitoring control communication cable according to any one of claims 4 to 8, further comprising a step of storing a measured value of a distance from a pulse signal transmission position to the fault location.

10. The wired distribution line remote monitoring according to claim 4, wherein the pulse width of the pulse signal is set wider as the distance is longer according to a distance range from the pulse signal transmission position to the failure location. A fault location method for control communication cables.

11. The wired distribution line remote monitoring control communication cable according to claim 1, wherein at least one of the arbitrary portion and another portion is a communication pot provided in advance in the communication cable. Fault point exploration and orientation method.

A transmission circuit for generating a monitoring signal of known characteristics, and the monitoring signal corresponding to a distribution line, laid so as to connect a master station and a plurality of slave stations, and for monitoring and controlling the distribution system A monitoring signal injection device provided with a coupling means for coupling and injecting to any location other than the master station of the communication cable for remote monitoring and control of the wired distribution line,
Coupling means for detecting at least one of the current and voltage by coupling to another location other than the master station of the communication cable , and the current and voltage components of the monitoring signal from at least one of the detected current and voltage Filter means for extracting at least one of the following: means for storing at least one reference value of the voltage and current of the monitoring signal predicted at the injection point of the monitoring signal; and at least one of the voltage and current of the extracted monitoring signal A processing circuit that compares one size with the reference value and determines whether or not the failure point of the communication cable is on the signal injection point side starting from the monitoring signal detection point according to the comparison result. A fault point search device for a communication cable for remote monitoring and control of a wired distribution line, comprising a combination with a detection device provided.

The detection device further includes means for detecting a data error of a remote monitoring control signal transmitted over the cable, and the processing circuit takes into consideration the presence or absence of the data error in addition to the comparison result, 13. The wired distribution line remote monitoring control communication cable according to claim 12, wherein it is determined whether or not a fault location of the communication cable is on the signal injection point side with a monitoring signal detection point as a starting point. Failure point exploration equipment.

At least the determination result of whether or not the voltage of the monitoring signal extracted, the magnitude of the current, and the failure point of the communication cable are on the signal injection point side starting from the monitoring signal detection point is detected by the detection device. The processing circuit further includes a memory for storing one, and based on the stored data, the processing circuit determines whether or not the failure point of the communication cable is on the signal injection point side starting from the monitoring signal detection point The failure point searching device for a communication cable for remote monitoring and control of a wired distribution line according to claim 12, wherein:

15. The wired distribution line remote monitoring control communication cable according to claim 13 or 14, wherein the memory further stores the presence or absence of a data error in the remote monitoring control signal received by the detection device. Obstacle point exploration device.

The transmission circuit generates a plurality of types of monitoring signals having different characteristics, and the monitoring signal injection device injects the monitoring signals having different characteristics into each of a plurality of pairs of communication cables arranged in parallel. The fault point investigation apparatus of the communication cable for wired type distribution line remote monitoring control in any one of 12-15.

The wired point distribution line remote monitoring control communication cable fault point search device according to claim 16, wherein the plurality of types of monitoring signals having different characteristics have different phases at the same frequency.

A transmission circuit for generating a monitoring signal of known characteristics, and the monitoring signal corresponding to a distribution line, laid so as to connect a master station and a plurality of slave stations, and for monitoring and controlling the distribution system A monitoring signal injection device provided with a coupling means for coupling and injecting to any location other than the master station of the communication cable for remote monitoring and control of the wired distribution line,
Coupling means for detecting at least one of the current and voltage by coupling to another location other than the master station of the communication cable , and the current and voltage components of the monitoring signal from at least one of the detected current and voltage Filter means for extracting at least one of the above, means for storing at least one reference value of the voltage and current of the monitoring signal predicted at the detection location of the monitoring signal, and at least one of the voltage and current of the extracted monitoring signal A processing circuit that compares one size with the reference value and determines whether or not the failure point of the communication cable is on the signal injection point side starting from the monitoring signal detection point according to the comparison result. An equipped fault detection device;
A pulse transmission circuit for injecting a pulse signal into a planned distance range of the communication cable fault narrowed down by the fault detection device, a filter circuit for taking in the pulse signal on the communication cable, and a pulse taken in from the injected pulse signal A processing arithmetic circuit for locating the distance to the failure point based on the signal delay time is provided, and is composed of a combination with a pulse radar type failure point locating device activated in response to the failure detection from the failure detection device. A fault location system for a communication cable for remote monitoring control of a wired distribution line characterized by the above.

19. The fault location of a communication cable for remote monitoring and control of a wired distribution line according to claim 18, wherein the fault detection device and the pulse radar type fault location device are connected to a common communication pot of the communication cable. apparatus.

20. The failure point locating apparatus for a wired distribution line remote monitoring control communication cable according to claim 18 or 19, wherein the communication cable comprises a plurality of lines, and pulse injection timing to each line is shifted.