JP2004170172A

JP2004170172A - Electric field and magnetic field sensor

Info

Publication number: JP2004170172A
Application number: JP2002334716A
Authority: JP
Inventors: Nobutaka Fukui; 信孝福井
Original assignee: HOKKEI IND CO Ltd; HOKKEI INDUSTRIES CO Ltd
Current assignee: HOKKEI IND CO Ltd; HOKKEI INDUSTRIES CO Ltd
Priority date: 2002-11-19
Filing date: 2002-11-19
Publication date: 2004-06-17

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric field and magnetic field sensor in which voltage and current can be measured by one sensor in non-contact with a power transmission and distribution line and the like and which can detect a magnetic field of a high frequency wave without being influenced by an electric field terminal provided at an outer peripheral side and whose measured voltage value compensates electric field detection change by rain water. <P>SOLUTION: With a magnetic field detection coil 21 mounted in a case 22 and a plurality of conductive bodies 25 in a wire shape provided with a predetermined clearance at outer peripheral of the case 22 in a exposing manner, magnetic flux is not shielded as it runs through a clearance provided between the plurality of conductive bodies on an outer peripheral side and high frequency magnetic field is detected by the mounted magnetic field detection coil 21 and magnetic field detection intensity does not change as magnetic field detection takes precedence of water film. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、電力設備である送配電線路や変電設備の送電電圧と送電電流現象を非接触で測定するために用いる電界磁界センサに関し、特に、高周波磁界および降雨時電界の検出対策を施した電界磁界センサに関する。
【０００２】
【従来の技術】
〔全体技術〕
電力設備の送電時や故障時の電圧測定には、変成器、抵抗分圧器、コンデンサ分圧器、碍子分圧器、光ＰＴ、電界検出器等が用いられ、電流測定には、変流器、Ｚ型ＣＴ、ホールＣＴ、光ＣＴ、磁界検出器等が用いられる。
【０００３】
電圧測定に用いる変成器、抵抗分圧器、コンデンサ分圧器、碍子分圧器は、電力線へ直接に接続するため、耐電圧を考慮した設計をしなければならず、このため大型、高価になり、商用周波に対しての特性はあるが、故障時の電圧現象、たとえば雷故障のような現象に起因する高周波電圧に対する周波数特性はない。光ＰＴは、商用周波から高周波に対して特性はあるが、電力線を通す必要があるため装着が大変である。電界検出器は、電力設備に非接触で商用周波から高周波までの特性を得ているが、雨の影響を受けて検出出力が変動しやすい。
【０００４】
電流測定に用いる変流器は、電力線を接続する必要があり、高周波特性がない。Ｚ型ＣＴは電力線を通す必要があり、耐電圧を考慮して地中線化する必要があり、高周波特性も良くない。ホールＣＴは、周波数特性はあるが地中線に接触させる必要がある。光ＣＴも、周波数特性はあるが電力線に取り付ける必要がある。磁界検出器は電力線に非接触で周波数特性もよい。
【０００５】
従来架空送電線路において送電電圧と送電電流現象を非接触で測定するために用いられているシステムを説明する（例えば、特許文献１参照）。
図１は架空送電線路の略図で、図中１は供給側の電気所（送電用設備）、２は変圧器の中性点抵抗器、３は三相架空送電線、４は需要側の電気所である。図２は送電鉄塔に電界磁界センサを配置した状態を示す概念図で、図中５は図１に示す架空送電線３の鉄塔、３ａ、３ｂ、３ｃは架空送電線、６ａ、６ｂ、６ｃは電界磁界センサであり、これらセンサは送電線３ａ、３ｂ、３ｃに対して非接触で対向している。なお以下では送電線３ａ、３ｂ、３ｃや電界磁界センサ６ａ、６ｂ、６ｃのいずれかを特定して示す以外は単に送電線３、電界磁界センサ６という。
【０００６】
図３は変電設備の架台に電界磁界センサを配置した状態を示す概念図で、図中７は図１に示す架空送電線３へ電気を送電するための送電用設備の架台または電気を受電する需要側の電気所４の受電用設備の架台であり、いずれの場合も図２と同様に電界磁界センサ６は、送電線３に対し非接触で対向している。
【０００７】
〔従来技術１〕
図４は特公平６−７０６６５号公報に記載された電界磁界センサの断面図である。図中、８は芯材、９は磁界検出巻線コイル、１０は電界極板兼用の箔板状のコイルシールド板、１１は外装で、これらをほぼ同心に配置してある。
【０００８】
〔従来技術２〕
他の形式の電界磁界センサとして図５に示すものが開発された。図中、９は電流を検出するための磁界コイル、１０は電圧を検出するための電界極、１２は電界極を固定するための絶縁パイプ、１３は接続箱で、同軸ケーブル１４（たとえば１．５Ｄ２Ｖ２本を収容したケーブル及び電界極１０と磁界コイル９のリード線）が配線してある。また図中１５はケーブル１４のコネクタで、１６は電界磁界センサ６を鉄塔５や架台７に設置するための取り付けネジである。この従来の電界磁界センサ６は、送電線３に非接触で商用周波から高周波までの周波数特性がある。
【０００９】
ところで図４、５に示した従来の電界磁界センサ６は、電界センサと磁界センサを別体、別置する場合に比べてコスト面と限られた場所に２個のセンサを設置しなくて済み、１個のセンサで電圧と電流を測定することが可能になり、送電電圧値と電流値に対し正比例し、電力線３と電界磁界センサ６との距離に反比例する特性でセンサ検出信号を積分手段その他の電気回路で処理し、電気故障現象を解析していた。
【００１０】
ところが、図４の従来技術１の電界磁界センサを実験した結果、電気故障時に発生する高周波の磁界に対して、安定的な検出ができない場合があることが判明した。
その理由は、磁界検出巻線コイル９の外周側に略円筒状のコイルシールド板（電界極板）１０を配置しているため、磁界がコイルシールド板に遮蔽され高周波になるほど減衰することであった。
【００１１】
又、図５の従来技術２の電界磁界センサ６は、電界極１０で検出した電界値が雨等の影響を受けて変化しやすく、この現象は、電圧計測に対し性能を左右する大きな欠点である。
その原因は、雨水が絶縁パイプ１２と接続箱１３に溜まり、電界磁界センサ６の取り付け部材である鉄塔５や架台７に雨水が接触している時は電界極１０で検出した微弱電流が水膜を通って大地へ分流されて感度が低くなる。他方、雨水が絶縁パイプ１２と接続箱１３に溜まり水膜を介して電界極１０と接触し、鉄塔５や架台７と接触していない時は、雨水による水膜も電界極となって電界極面積を増やすことにより感度が高くなるためである。上記２原因により、非降雨時に比して降雨時は検出した電界値が増減する。
ただし電流測定に対しては、磁界コイル９を固定している絶縁パイプ１２が樹脂で磁束を通すため、周波数特性は良い。
【００１２】
【特許文献１】
特公平６−７０６６５号公報
【００１３】
【発明が解決しようとする課題】
本発明は、送配電線等に非接触で電圧と電流を１個のセンサで測定でき、外周側に配置した電界極に影響されずに高周波の磁界を内装した磁界コイルで検出出来ると共に、測定した電圧値が雨水の影響を受けることなく雨水による電界検出変化を補う様にした電界磁界センサを提供する。
【００１４】
【課題を解決するための手段】
本発明は、上記従来技術に基づく、電気故障時に発生する高周波磁界の検出に難点が有ったり、降雨時の水膜で電界極面積が変化し電界検出強度が変化する課題に鑑み、ケースの内部に磁界検出コイルを内装すると共に、ケースの外周にワイヤ状の複数の導電体を所定間隔を有して露出配置することによって、ケース外周に配置された複数の導電体の間に設定された隙間を通って磁束は遮蔽されず、ケースに内装した磁界検出コイルで高周波磁界を検出すると共に、水膜の影響を受けない様にして、上記課題を解決する。
【００１５】
【発明の実施の形態】
以下本発明の実施の形態を図面を参照して説明する。なお以下では従来と共通する部分には共通する符号を付すにとどめ重複する説明は省略する。
図６は本発明に係る電界磁界センサの一実施形態の構成を示す断面図、図７は図６のＡ−Ａ断面図、図８はキャップ側からの電界磁界センサの平面図、図９は自由端面の形状変更例（２種）を示す図、図１０は磁界検出コイルの取付方向を変化させた電界磁界センサの構成を示した断面図、図１１は送電鉄塔に電界磁界センサを縦方向に配置した状態を示す概念図である。
図中、２０は電界極、２１は磁界コイル、２２は樹脂製ケース、２３は固定（取付）端面側の樹脂製ブラケット、２４は自由端面側の樹脂製ブラケットで電界磁界センサ６を縦方向に設置した時のキャップ、２５はケース２２の外周に設けた導電体で一方の電界極２０と成るもの、２６はブラケット２４の外側に設けた導電体で他方の電界極２０と成るもの、２７は連結部材のステンレスパイプ、２８は接続箱、２９は同軸ケーブル、３０はケーブルコネクタ、３１は取り付けネジである。
そして、図６に示す様に、電界検出部である電界極２０と磁界検出部である磁界コイル２１を一体化して円筒状の検出部と成し、電界極２０は検出部の筒状部外周面（外壁部材）に設けると共に、磁界コイル２１は検出部の内部に装着している。
【００１６】
本実施形態の電界磁界センサ６の具体例は、図６、７に示す様に、磁束を通す樹脂製の円筒状のケース２２の外周面（上下２開口面を除く）に凹溝３２を設けると共に、該凹溝３２に一部が嵌合状態で、ケース２２の外周面にステンレス製のワイヤ２５を螺旋状に巻き付けている。この巻き付け状態により、電界検出部となる導電体のワイヤ２５はケース２２の外周面に露出配置されると共に、平行するワイヤ２５の間に所定間隔の隙間が形成される。
尚、ワイヤ２５は螺旋状に巻き付けたが、ワイヤ２５は所定間隔を有して複数を配置出来ればその巻き付け方法（配置状態）は限定されず、例えば、複数本の導電体を円周上に平行に巻き付けても良く、実施例の螺旋状のものは円周に沿うと共に傾斜平行の複数本の導電体を１本に連結したものに相当する。
或いは、複数本の導電体の配置状態を前述例の直交方向である母線方向（円周面における軸線方向）に平行配置したり、縦横（交差２方向）に複数本の導電体を夫々配置して網目状に配置しても良く、即ち、複数本の導電体の間に所定間隔の隙間を設ける様に配置する。
【００１７】
図６に示す様に、円筒状ケース２２の内部に磁界コイル２１を装着すると共に、ケース２２の上下両端開口端面（ワイヤ２５を配置したケース２２外周以外の２面）にブラケット２３、２４を固定し、一方（縦方向設置時の下方）を固定端面と成すと共に、他方（同、上方）を自由端面と成し、本件明細書中、上方のブラケット２４を縦方向設置時にキャップと称する。
下方のブラケット２３の底部３３は、雨水で接続箱２８との連結部材であるステンレスパイプ２７が濡れないよう凹状に形成してある。
そして、下端部（固定端）のブラケット２３の凹状底部中央にブラケット２３に比して小径のステンレスパイプ２７の上端を固定し、ステンレスパイプ２７の下端を接続箱２８に固定している。
【００１８】
磁界検出コイル２１は、商用周波から高周波の周波数特性とコイル出力電圧の大きさとを考慮し、ボビン３４に数百回電線３５を巻いて構成してある。
電力線３と電界磁界センサ６の関係において、磁界検出コイル２１の装着方向は図６又は図１０の様になり、又電界磁界センサ６は図６、１１の様に直立状態で取り付けられたり、図９の様に横向状態で取り付けられる。
【００１９】
図６、８に示す様に、ケース２２（検出部）の頂部（自由端）を覆うキャップ（ブラケット２４）は、磁束を遮蔽することがなく、また雨水が落ちやすくなるように円錐形状の樹脂製で形成してある。また、雨水で濡れても電界検出状態が変化しないように、たとえばステンレス製のワイヤ２６を縫うようにして外面に露出させて設けてある。
詳しくは、キャップの傾斜面にワイヤ２６の露出部を放射状に複数配置すると共に、露出したワイヤ２６の両端部をキャップの傾斜面等を貫通させて裏面側で結線している。キャップに露出配置したワイヤ２６は、ケース２２外周面に設けたワイヤ２５とキャップ下方の円筒状ケース２２内で電線接続し、ケース２２外周のワイヤ２５の他、キャップ（ブラケット２４）外側面のワイヤ２６も電界極２０の一部と成している。もちろんキャップの形状は、雨水が流れ落ちやすければ角錐等であってもよい。
【００２０】
尚、ケース２２自由端に設けたブラケット２４は、電界磁界センサ６を縦方向設置した場合は錐形キャップと成したが、図９に示す様に、横方向設置とする場合には、（ａ）の様に垂直端面としたり、（ｂ）の様に錐形その他形状の陥没端面としても良い。
【００２１】
図６に示す様に、検出部と接続箱２８を固定するステンレスパイプ２７内に電界極２０（ワイヤ２５およびワイヤ２６）と磁界検出コイル２１の信号を流すための電線を収容し、ステンレスパイプ２７の外装材としては、雨水を弾く材質、たとえばテフロン（登録商標）製の収縮チューブを装着して保護してある。
【００２２】
次に、上述の構造による作用について説明する。
電界極２０としてケース２２の外周面に設けたワイヤ２５は、所定間隔を有した螺旋状に略平行配置していることにより、複数のワイヤ２５間の隙間が電力線３の電流による磁束を遮蔽することなく、ケース２２に内装した磁界検出コイル２１で検出し得る。
【００２３】
キャップ（ブラケット２４）に設けたワイヤ２６は電界極２０の一部となり、電界極２０はケース２２とブラケット２４の両者に設けたワイヤ２５、２６で、ケース２２の外周面以外にも配置されると共に、電界極２０の絶対量（長）が増大して、電界を検出する。
【００２４】
更に、降雨時の雨水がケース２２およびキャップ等に付着して水膜が発生しても、キャップ等の表面に露出させて設けたワイヤ２５、２６は水膜より導電性が高く、電界が通常集中する効果があるため、雨水に拘わらず電界極２０はケース２２のワイヤ２５およびキャップのワイヤ２６となるため、雨水で検出部が濡れても電界検出強度が変わらない。
又、雨水で検出部や接続箱２８が濡れても、検出部の底部（ブラケット２３の底部３３）が凹状であることにより、検出部の外周面（ワイヤ２５）等と連結部材のステンレスパイプ２７は非接触、離隔しているため、鉄塔５や架台７へ検出した電界の微弱電流が漏洩しない。
したがって、降雨時であっても非降雨時と同様に雨水に影響されずに、送電電圧現象を検出する。
【００２５】
なお、図６の例において、電流を検出するコイル２１を接続箱２８内に収めて電界検出部と磁界検出部を別体化すると、送電線等と電界極２０、磁界コイル２１との距離と角度が違ってくるため、センサ出力を加算して得る零相電圧や零相電流等を正しく得ることができなくなる。
【００２６】
【発明の効果】
要するに本発明は、ケース２２の内部に磁界検出コイル２１を内装すると共に、ケース２２の外周にワイヤ状の複数の導電体（ワイヤ２５）を所定間隔を有して露出配置したので、電界検出部（導電体）と磁界検出部（磁界検出コイル）を一体化したことにより、送電線等に非接触で電圧と電流が１個の電界磁界センサ６で測定でき、コスト的にも、設置スペース的にも有利なだけでなく、複数の導電体の間に多量の隙間が設定されることにより、磁束は隙間を通って遮蔽されることなく、高周波磁界の検出に悪影響を及ぼさずに測定することが出来、更に、雨水でケース２２外周が濡れても、水膜より電界検出が優先されるため電界検出強度が変わらず、送電電圧現象を雨水の影響を受けることなく安定的に検出することが出来る。
【００２７】
ケース２２の外周に導電体を螺旋状に露出配置したので、導電体を所定間隔を有した状態でケース２２の外周へ均等に露出配置し、電界を安定的に検出することが出来る。
【００２８】
ケース２２の外周に設けた凹溝３２にワイヤ状の導電体を露出配置したので、ワイヤ状導電体は凹溝３２で配置位置が特定され、導電体間の所定間隔を維持したり、巻き付けを容易に行うことが出来る。
【００２９】
導電体を配置したケース２２外周以外の２面中、の１面（ブラケット２３）を固定端面と成すと共に、他面（ブラケット２４）を自由端面と成し、該自由端面にワイヤ状の導電体を少なくとも一ヶ所以上で露出させ、該導電体をケース２２外周の導電体（ワイヤ２５）に接続したので、外周側面の導電体とは方向相違箇所に別途配置すると共に、配置箇所が増加して、電界を安定的に検出することが出来る。
【００３０】
自由端面をケース２２の頂部を覆う錐形のキャップ（ブラケット２４）と成したので、キャップへの降雨時の雨水が流下し易くて水膜形成を抑制することが出来、雨水でキャップが濡れても電界検出強度の変化を低減し、送電電圧現象を雨水の影響を受けることなく安定的に検出することが出来る。
【００３１】
凹状に形成したケース２２の底部３３に連結部材（ステンレスパイプ２７）を取付けると共に、該連結部材の下端を接続箱２８に取付けたので、検出した電界の微弱電流が鉄塔等に漏洩しないため、送電電圧現象を雨水の影響を受けることなく安定的に検出することが出来る等その実用的効果甚だ大である。
【図面の簡単な説明】
【図１】電力設備の系統を示す架空送電線路の概念図である。
【図２】送電鉄塔に電界磁界センサを配置した状態を示す概念図である。
【図３】変電設備の架台に電界磁界センサを配置した状態を示す概念図である。
【図４】従来の電界磁界センサの構成を簡単に示した概念図である。
【図５】他の従来の電界磁界センサの構成を簡単に示した概念図である。
【図６】本発明に係る電界磁界センサの一実施形態の構成を示した断面図である。
【図７】図６のＡ−Ａ断面図である。
【図８】キャップ（電界磁界センサ）の平面図である。
【図９】自由端面の他例を示す図である。
【図１０】磁界検出コイルの取付方向を変化させた電界磁界センサの構成を示した断面図である。
【図１１】送電鉄塔に電界磁界センサを縦方向に配置した状態を示す概念図である。
【符号の説明】
２０電界極
２１磁界コイル
２２ケース
２３ブラケット
２４ブラケット
２５ワイヤ
２６ワイヤ
２８接続箱
３２凹溝
３３底部[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an electric field magnetic field sensor used for non-contact measurement of transmission voltage and transmission current phenomena of power transmission and distribution lines and substation equipment, and more particularly, to an electric field with measures for detecting a high-frequency magnetic field and a rainfall electric field. The present invention relates to a magnetic field sensor.
[0002]
[Prior art]
[Overall technology]
Transformers, resistance voltage dividers, capacitor voltage dividers, insulator voltage dividers, optical PTs, electric field detectors, etc. are used for voltage measurement during power transmission or failure of power equipment, and current transformers, Z A type CT, a hole CT, an optical CT, a magnetic field detector, and the like are used.
[0003]
Transformers, resistor dividers, capacitor dividers, and insulator dividers used for voltage measurement must be designed in consideration of the withstand voltage because they are directly connected to the power line. Although there is a characteristic with respect to the frequency, there is no frequency characteristic with respect to a high-frequency voltage caused by a voltage phenomenon at the time of failure, for example, a phenomenon such as a lightning failure. The optical PT has characteristics from a commercial frequency to a high frequency, but is difficult to mount because it needs to pass through a power line. The electric field detector obtains characteristics from a commercial frequency to a high frequency without contacting the power equipment, but the detection output tends to fluctuate under the influence of rain.
[0004]
The current transformer used for current measurement needs to be connected to a power line and has no high-frequency characteristics. The Z-type CT needs to pass through a power line, needs to be undergrounded in consideration of withstand voltage, and has poor high-frequency characteristics. Hall CT has frequency characteristics, but needs to be in contact with the underground wire. Optical CT also has frequency characteristics, but needs to be attached to a power line. The magnetic field detector has good frequency characteristics without contacting the power line.
[0005]
A system conventionally used for non-contact measurement of a transmission voltage and a transmission current phenomenon in an overhead transmission line will be described (for example, see Patent Document 1).
FIG. 1 is a schematic diagram of an overhead transmission line, in which 1 is an electric station on the supply side (power transmission equipment), 2 is a neutral point resistor of a transformer, 3 is a three-phase overhead transmission line, and 4 is electricity on the demand side. Place. FIG. 2 is a conceptual diagram showing a state in which an electric field magnetic field sensor is arranged on a power transmission tower. In the figure, reference numeral 5 denotes a tower of the overhead transmission line 3 shown in FIG. 1, 3a, 3b, and 3c indicate overhead transmission lines, and 6a, 6b, and 6c indicate These sensors are electric field sensors, which face the power transmission lines 3a, 3b, 3c in a non-contact manner. In the following description, the transmission lines 3a, 3b, and 3c and the electric field magnetic field sensors 6a, 6b, and 6c are simply referred to as the transmission line 3 and the electric field magnetic field sensor 6 except for specifying one of them.
[0006]
FIG. 3 is a conceptual diagram showing a state in which an electric field magnetic field sensor is arranged on a base of a substation facility. In the figure, reference numeral 7 denotes a base of a power transmission facility for transmitting electricity to the overhead transmission line 3 shown in FIG. 1 or receives electricity. It is a frame of the power receiving equipment of the electric station 4 on the demand side. In each case, the electric field magnetic field sensor 6 faces the transmission line 3 in a non-contact manner as in FIG.
[0007]
[Prior art 1]
FIG. 4 is a sectional view of an electric field magnetic field sensor described in Japanese Patent Publication No. 6-70665. In the figure, 8 is a core material, 9 is a magnetic field detection winding coil, 10 is a foil-shaped coil shield plate also serving as an electric field electrode plate, and 11 is an exterior, which are arranged substantially concentrically.
[0008]
[Prior art 2]
Another type of electric field sensor was developed as shown in FIG. In the figure, 9 is a magnetic field coil for detecting a current, 10 is an electric field pole for detecting a voltage, 12 is an insulating pipe for fixing the electric field pole, 13 is a junction box, and a coaxial cable 14 (for example, 1.. Cables accommodating two 5D2V cables and lead wires of the electric field pole 10 and the magnetic field coil 9) are wired. In the figure, reference numeral 15 denotes a connector of the cable 14, and 16 denotes a mounting screw for installing the electric field magnetic field sensor 6 on the steel tower 5 or the gantry 7. This conventional electric field magnetic field sensor 6 has a frequency characteristic from a commercial frequency to a high frequency without contacting the transmission line 3.
[0009]
By the way, the conventional electric field magnetic field sensor 6 shown in FIGS. 4 and 5 does not require two sensors to be installed in a place where cost is limited compared to a case where the electric field sensor and the magnetic field sensor are separately provided and separately provided. The voltage and current can be measured with a single sensor, and the sensor detection signal is integrated with a characteristic that is directly proportional to the transmission voltage value and the current value and inversely proportional to the distance between the power line 3 and the electric field magnetic field sensor 6. It was processed by other electric circuits to analyze the electric failure phenomenon.
[0010]
However, as a result of conducting an experiment on the electric field magnetic field sensor of the prior art 1 shown in FIG.
The reason is that the substantially cylindrical coil shield plate (electric field electrode plate) 10 is arranged on the outer peripheral side of the magnetic field detection winding coil 9, so that the magnetic field is shielded by the coil shield plate and attenuated as the frequency becomes higher. Was.
[0011]
Further, the electric field magnetic field sensor 6 of the prior art 2 shown in FIG. 5 easily changes the electric field value detected by the electric field pole 10 due to the influence of rain or the like. is there.
The reason is that when rainwater accumulates in the insulating pipe 12 and the junction box 13 and the rainwater is in contact with the steel tower 5 or the gantry 7 as the mounting member of the electric field magnetic field sensor 6, the weak current detected by the electric field pole 10 causes a water film. Through the earth to lower the sensitivity. On the other hand, when the rainwater accumulates in the insulating pipe 12 and the connection box 13 and contacts the electric field pole 10 via the water film and does not contact the steel tower 5 or the gantry 7, the water film due to the rainwater also becomes the electric field electrode and becomes an electric field electrode. This is because the sensitivity is increased by increasing the area. Due to the two causes described above, the detected electric field value increases or decreases during rainfall as compared to during non-rainfall.
However, for current measurement, the insulating pipe 12 to which the magnetic field coil 9 is fixed passes magnetic flux with resin, so that the frequency characteristics are good.
[0012]
[Patent Document 1]
Japanese Patent Publication No. 6-70665
[Problems to be solved by the invention]
The present invention is capable of measuring voltage and current with a single sensor in a non-contact manner to a transmission and distribution line, and detecting and measuring a high-frequency magnetic field with a built-in magnetic field coil without being affected by an electric field pole arranged on an outer peripheral side. Provided is an electric field magnetic field sensor in which a detected voltage value compensates for an electric field detection change due to rainwater without being affected by rainwater.
[0014]
[Means for Solving the Problems]
The present invention is based on the prior art described above, and there is a difficulty in detecting a high-frequency magnetic field generated at the time of an electrical failure, or in view of the problem that the electric field detection area changes due to a change in the field pole area in a water film during rainfall, A magnetic field detection coil is internally provided, and a plurality of wire-shaped conductors are exposed and arranged at predetermined intervals on the outer periphery of the case, thereby being set between the plurality of conductors arranged on the outer periphery of the case. A magnetic flux is not shielded through a gap, a high-frequency magnetic field is detected by a magnetic field detection coil provided in a case, and the above-mentioned problem is solved without being affected by a water film.
[0015]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following, portions common to the related art will be denoted by the same reference numerals, and redundant description will be omitted.
6 is a cross-sectional view showing the configuration of an embodiment of the electric field magnetic field sensor according to the present invention, FIG. 7 is a cross-sectional view taken along line AA of FIG. 6, FIG. 8 is a plan view of the electric field magnetic field sensor from the cap side, and FIG. FIG. 10 is a cross-sectional view illustrating a configuration of an electric field magnetic field sensor in which a mounting direction of a magnetic field detecting coil is changed, and FIG. 11 is a vertical view of an electric field magnetic field sensor on a power transmission tower. FIG. 3 is a conceptual diagram showing a state where the components are arranged in a circle.
In the figure, 20 is an electric field pole, 21 is a magnetic field coil, 22 is a resin case, 23 is a resin bracket on the fixed (attached) end surface side, 24 is a resin bracket on the free end surface side, and the electric field magnetic field sensor 6 is arranged in the vertical direction. The cap when installed, 25 is a conductor provided on the outer periphery of the case 22 and forms one electric field electrode 20, 26 is a conductor provided on the outside of the bracket 24 and forms the other electric field electrode 20, 27 is a conductor The connecting member is a stainless steel pipe, 28 is a connection box, 29 is a coaxial cable, 30 is a cable connector, and 31 is a mounting screw.
Then, as shown in FIG. 6, an electric field pole 20 as an electric field detecting section and a magnetic field coil 21 as a magnetic field detecting section are integrated to form a cylindrical detecting section. The magnetic field coil 21 is mounted on the surface (outer wall member), and is mounted inside the detection unit.
[0016]
In a specific example of the electric field magnetic field sensor 6 of the present embodiment, as shown in FIGS. 6 and 7, a concave groove 32 is provided on the outer peripheral surface (excluding upper and lower opening surfaces) of a resin-made cylindrical case 22 through which magnetic flux passes. At the same time, a stainless steel wire 25 is spirally wound around the outer peripheral surface of the case 22 with a part fitted in the concave groove 32. By this winding state, the conductor wire 25 serving as the electric field detection unit is exposed and arranged on the outer peripheral surface of the case 22, and a predetermined gap is formed between the parallel wires 25.
Note that the wire 25 is spirally wound, but the winding method (arrangement state) is not limited as long as a plurality of wires 25 can be arranged at a predetermined interval. For example, a plurality of conductors are wound around the circumference. The spiral shape may be wound in parallel, and the spiral shape in the embodiment corresponds to a structure in which a plurality of conductors extending along the circumference and inclined in parallel are connected to one.
Alternatively, the arrangement state of the plurality of conductors may be arranged in parallel to the generatrix direction (axial direction on the circumferential surface) which is the orthogonal direction of the above example, or the plurality of conductors may be arranged vertically and horizontally (two directions of intersection). The conductors may be arranged in a mesh shape, that is, they are arranged so as to provide a predetermined gap between a plurality of conductors.
[0017]
As shown in FIG. 6, the magnetic field coil 21 is mounted inside the cylindrical case 22, and the brackets 23 and 24 are fixed to the open end surfaces of the upper and lower ends of the case 22 (two surfaces other than the outer periphery of the case 22 where the wires 25 are arranged). One (the lower part in the vertical installation) forms a fixed end face, and the other (the same, upper part) forms a free end face. In this specification, the upper bracket 24 is referred to as a cap during the vertical installation.
The bottom portion 33 of the lower bracket 23 is formed in a concave shape so that the stainless steel pipe 27 as a connecting member to the connection box 28 does not get wet with rainwater.
The upper end of the stainless steel pipe 27 having a smaller diameter than the bracket 23 is fixed to the center of the concave bottom of the bracket 23 at the lower end (fixed end), and the lower end of the stainless steel pipe 27 is fixed to the connection box 28.
[0018]
The magnetic field detection coil 21 is configured by winding the electric wire 35 around the bobbin 34 several times in consideration of the frequency characteristics from the commercial frequency to the high frequency and the magnitude of the coil output voltage.
In the relationship between the power line 3 and the electric field magnetic field sensor 6, the mounting direction of the magnetic field detecting coil 21 is as shown in FIG. 6 or FIG. 10, and the electric field magnetic field sensor 6 is mounted upright as shown in FIG. As shown in FIG.
[0019]
As shown in FIGS. 6 and 8, a cap (bracket 24) that covers the top (free end) of the case 22 (detection unit) does not shield magnetic flux and has a conical resin shape so that rainwater easily falls. Formed. Further, a stainless steel wire 26 is sewn, for example, so as to be exposed on the outer surface so that the electric field detection state does not change even when wet with rainwater.
More specifically, a plurality of exposed portions of the wire 26 are radially arranged on the inclined surface of the cap, and both ends of the exposed wire 26 are connected on the back surface side through the inclined surface of the cap and the like. The wire 26 exposed on the cap is connected to the wire 25 provided on the outer peripheral surface of the case 22 in the cylindrical case 22 below the cap, and the wire 25 on the outer periphery of the case 22 and the wire on the outer surface of the cap (bracket 24) are connected. 26 also forms a part of the electric field pole 20. Of course, the shape of the cap may be a pyramid or the like as long as the rainwater easily flows down.
[0020]
The bracket 24 provided at the free end of the case 22 is formed as a conical cap when the electric field sensor 6 is installed in the vertical direction. However, as shown in FIG. ), Or may be a conical or other depressed end face as shown in FIG.
[0021]
As shown in FIG. 6, an electric wire for flowing signals of the electric field pole 20 (wires 25 and 26) and the magnetic field detection coil 21 is accommodated in a stainless steel pipe 27 for fixing the detection unit and the connection box 28, and the stainless steel pipe 27 is fixed. Is protected by attaching a shrinkable tube made of a material that repels rainwater, for example, Teflon (registered trademark).
[0022]
Next, the operation of the above structure will be described.
The wires 25 provided on the outer peripheral surface of the case 22 as the electric field poles 20 are spirally arranged substantially in parallel with a predetermined interval, so that the gap between the plurality of wires 25 shields magnetic flux due to the current of the power line 3. Without this, detection can be performed by the magnetic field detection coil 21 provided inside the case 22.
[0023]
The wire 26 provided on the cap (bracket 24) becomes a part of the electric field electrode 20, and the electric field electrode 20 is wires 25 and 26 provided on both the case 22 and the bracket 24, and is disposed on the outer peripheral surface of the case 22. At the same time, the absolute amount (length) of the electric field pole 20 increases, and the electric field is detected.
[0024]
Furthermore, even if rainwater during rainfall adheres to the case 22 and the cap and the like to form a water film, the wires 25 and 26 exposed and provided on the surface of the cap and the like have higher conductivity than the water film, and the electric field is usually lower. Since there is an effect of concentration, the electric field electrode 20 becomes the wire 25 of the case 22 and the wire 26 of the cap irrespective of the rainwater, so that the electric field detection intensity does not change even if the detection unit is wet with the rainwater.
Even if the detection unit and the connection box 28 are wet with rainwater, since the bottom of the detection unit (the bottom 33 of the bracket 23) is concave, the outer peripheral surface (the wire 25) of the detection unit and the stainless steel pipe 27 of the connecting member are used. Are not in contact with and separated from each other, so that the weak electric current of the detected electric field does not leak to the steel tower 5 or the gantry 7.
Therefore, even in the case of rainfall, the power transmission voltage phenomenon is detected without being affected by rainwater as in the case of non-rainfall.
[0025]
In the example of FIG. 6, when the coil 21 for detecting a current is housed in the connection box 28 and the electric field detection unit and the magnetic field detection unit are separated, the distance between the transmission line and the electric field pole 20 and the magnetic field coil 21 is reduced. Since the angles differ, it becomes impossible to correctly obtain a zero-phase voltage, a zero-phase current, or the like obtained by adding the sensor outputs.
[0026]
【The invention's effect】
In short, according to the present invention, the magnetic field detection coil 21 is provided inside the case 22 and a plurality of wire-like conductors (wires 25) are exposed and arranged at predetermined intervals on the outer periphery of the case 22. By integrating the (conductor) and the magnetic field detection unit (magnetic field detection coil), voltage and current can be measured by one electric field magnetic field sensor 6 without contact with power transmission lines, etc. Not only is it advantageous, but because a large amount of gap is set between multiple conductors, magnetic flux is not shielded through the gap, and measurement is performed without adversely affecting high frequency magnetic field detection Furthermore, even if the outer periphery of the case 22 is wet with rainwater, the electric field detection is given priority over the water film, so the electric field detection intensity does not change, and the transmission voltage phenomenon can be detected stably without being affected by the rainwater. I can do it.
[0027]
Since the conductor is spirally exposed on the outer periphery of the case 22, the conductor is uniformly exposed on the outer periphery of the case 22 with a predetermined interval, and the electric field can be stably detected.
[0028]
Since the wire-shaped conductor is exposed and arranged in the concave groove 32 provided on the outer periphery of the case 22, the arrangement position of the wire-shaped conductor is specified by the concave groove 32, and a predetermined interval between the conductors is maintained or winding is performed. It can be done easily.
[0029]
Of the two surfaces other than the outer periphery of the case 22 on which the conductor is disposed, one surface (bracket 23) is formed as a fixed end surface, and the other surface (bracket 24) is formed as a free end surface. Is exposed at least at one or more locations, and the conductor is connected to the conductor (wire 25) on the outer periphery of the case 22. Therefore, the conductor is separately arranged at a position different from the conductor on the outer peripheral side surface, and the arrangement location is increased. And the electric field can be stably detected.
[0030]
Since the free end face is formed as a conical cap (bracket 24) that covers the top of the case 22, rainwater during rainfall on the cap easily flows down, water film formation can be suppressed, and the cap wets with rainwater. Also, the change in the electric field detection intensity can be reduced, and the transmission voltage phenomenon can be stably detected without being affected by rainwater.
[0031]
Since the connecting member (stainless steel pipe 27) is attached to the bottom 33 of the concave case 22 and the lower end of the connecting member is attached to the connection box 28, the weak electric current of the detected electric field does not leak to the tower or the like. The practical effect is extremely large, for example, the voltage phenomenon can be stably detected without being affected by rainwater.
[Brief description of the drawings]
FIG. 1 is a conceptual diagram of an overhead transmission line showing a system of power equipment.
FIG. 2 is a conceptual diagram showing a state where an electric field magnetic field sensor is arranged on a power transmission tower.
FIG. 3 is a conceptual diagram showing a state where an electric field magnetic field sensor is arranged on a gantry of a substation facility.
FIG. 4 is a conceptual diagram simply showing the configuration of a conventional electric field magnetic field sensor.
FIG. 5 is a conceptual diagram simply showing a configuration of another conventional electric field magnetic field sensor.
FIG. 6 is a cross-sectional view illustrating a configuration of an embodiment of an electric field magnetic field sensor according to the present invention.
FIG. 7 is a sectional view taken along the line AA of FIG. 6;
FIG. 8 is a plan view of a cap (electric field sensor).
FIG. 9 is a view showing another example of the free end surface.
FIG. 10 is a cross-sectional view showing a configuration of an electric field magnetic field sensor in which a mounting direction of a magnetic field detection coil is changed.
FIG. 11 is a conceptual diagram showing a state in which an electric field magnetic field sensor is vertically arranged on a power transmission tower.
[Explanation of symbols]
Reference Signs List 20 electric field pole 21 magnetic field coil 22 case 23 bracket 24 bracket 25 wire 26 wire 28 connection box 32 concave groove 33 bottom

Claims

送配電線路や変電設備の送電電圧と送電電流現象を非接触で測定するための電界磁界センサであって、ケースの内部に磁界検出コイルを内装すると共に、ケースの外周にワイヤ状の複数の導電体を所定間隔を有して露出配置したことを特徴とする電界磁界センサ。An electric field magnetic field sensor for measuring the transmission voltage and transmission current phenomena of transmission and distribution lines and substation equipment in a non-contact manner.A magnetic field detection coil is provided inside the case, and a plurality of wire-shaped conductive An electric field magnetic field sensor wherein a body is exposed at a predetermined interval.

ケースの外周に導電体を螺旋状に露出配置したことを特徴とする請求項１記載の電界磁界センサ。2. The electric field magnetic field sensor according to claim 1, wherein a conductor is spirally exposed on the outer periphery of the case.

ケースの外周に設けた凹溝にワイヤ状の導電体を露出配置したことを特徴とする請求項１又は２記載の電界磁界センサ。3. The electric field magnetic field sensor according to claim 1, wherein a wire-shaped conductor is exposed in a concave groove provided on an outer periphery of the case.

導電体を配置したケース外周以外の２面中、１面を固定端面と成すと共に、他面を自由端面と成し、該自由端面にワイヤ状の導電体を少なくとも一ヶ所以上で露出させ、該導電体をケース外周の導電体に接続したことを特徴とする請求項１、２又は３記載の電界磁界センサ。Of the two surfaces other than the outer periphery of the case in which the conductor is disposed, one surface forms a fixed end surface, the other surface forms a free end surface, and a wire-like conductor is exposed at at least one or more places on the free end surface. 4. The electric field magnetic field sensor according to claim 1, wherein the conductor is connected to the conductor on the outer periphery of the case.

自由端面をケースの頂部を覆う錐形のキャップと成したことを特徴とする請求項４記載の電界磁界センサ。5. The electric field sensor according to claim 4, wherein the free end face is a conical cap covering the top of the case.

凹状に形成したケースの底部に連結部材を取付けると共に、該連結部材の下端を接続箱に取付けたことを特徴とする請求項５記載の電界磁界センサ。6. The electric field sensor according to claim 5, wherein a connecting member is attached to a bottom of the case formed in a concave shape, and a lower end of the connecting member is attached to a connection box.