JPH0378435A - Testing method of ground circuit of multi-branch switch - Google Patents

Abstract

PURPOSE:To test a ground circuit only by zero-phase currents by using the zero-phase currents of arbitrary one circuit as reference vector and deciding the presence of significance regarding phase difference with the zero-phase currents of residual circuits in the multi-branch switch of a power distribution system. CONSTITUTION:Outputs A'-F' from ZCTs at every circuit of a multi-branch switch are input to an arithmetic section through auxiliary transformers AXT, filters F, sample-and-hold sections SH, a multiplexer MPX and an A/D converter A/D. One circuit is used as a reference circuit and phase between zero-phase currents is compared through the system of the sum of products in the arithmetic section. That is, when the arithmetic result of the sum of products takes a negative value, significance is determined, and the circuit is decided to be a fault circuit when the number of circuits taking a negative value is one. When the number of circuits taking the negative value is the number of circuits minus one, the reference circuit is decided to be the fault circuit. Accordingly, a ground circuit can be tested only by zero-phase currents.

Description

【発明の詳細な説明】 〈産業上の利用分野〉 本発明は多分岐開閉装置に収納された複数の回線から地
絡回線を検出する検定方法に間する。DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention is directed to a verification method for detecting a ground fault line from a plurality of lines housed in a multi-branch switchgear.

〈従来の技術〉 非接地系の配電系統用に使用される、複数系統のケーブ
ル回線を集中して収納した多分岐開閉装置として、従来
、第５図、並びに第６図に例示する構成のものがあった
。第５図において、１０は多分岐開閉装置、１１は多分
岐開閉装置１〇−式を収容する外箱、１２は外Ｉ１１の
扉、１３はケーブル回線群Ａ−Ｆが立ち上がるケーブル
ビット、１４は地表面である。幹線から接地形計器用変
圧器ＧＰＴ（以下、ＧＰＴと表示する）とケーブル回線
群Ａ−Ｆとが分岐しており、以降各回線を区別する必要
が有るときは、回線Ａ、回線Ｂの如く英大文字Ａ−Ｆを
付して表記し、零相Ｘ流の場合には更にＯを何して例え
ばＩＡＯの如く表記することにする。各回線Ａ〜Ｆには
夫々に開閉器ＣＤ（以下、ＣＢと表記する）、零相変流
器ＺＣＴ（以下、ＺＣＴと表記する）、保護継電器等が
配設されているが、図の煩雑化を避けるため、第５図に
は回線毎にＺＣＴの記号のみを付して他は省略し、第６
図に１回線分についてその構成の概要を示している。<Prior art> As a multi-branch switchgear that is used for an ungrounded power distribution system and stores cable lines of multiple systems in a concentrated manner, the configurations illustrated in FIGS. 5 and 6 have conventionally been used. was there. In FIG. 5, 10 is a multi-branch switchgear, 11 is an outer box that accommodates the multi-branch switchgear 10-type, 12 is the door of the outside I11, 13 is a cable bit from which cable line groups A to F stand up, and 14 is a It is the ground surface. A grounded instrument transformer GPT (hereinafter referred to as GPT) and a cable line group A-F are branched from the main line, and when it is necessary to distinguish between each line from now on, they will be referred to as line A, line B, etc. It will be written with capital letters A-F, and in the case of zero-phase X flow, what is added to O and written as, for example, IAO. Each line A to F is equipped with a switch CD (hereinafter referred to as CB), a zero-phase current transformer ZCT (hereinafter referred to as ZCT), a protective relay, etc., but the diagram is complicated. In order to avoid confusion, only the ZCT symbol is attached to each line in Figure 5, and the others are omitted.
The figure shows an outline of the configuration for one line.

第６図において、ＤＧＲは回線の１線地絡を検出する方
向地絡＆Ｉ電器（以下ＤＧＲと表記する）で、ＧＰＴは
１次巻線を星形結線として中性点を直接接地し、中性点
電流Ｉｎは線路の静電容量ＣＡ−ＣＦに基づく充電電流
を系統に還流させており、ＧＰＴの３次巻線を開放デル
タ結線して零相電圧■０の検出に使用している、ｒ　１
１は制限抵抗器（Ｒｎは１次側換算値）、Ｒｇは地絡事
故点Ｇ（動作説明における例示的なもの）における地絡
抵抗で、ＺＣＴの２次側出力としての零相電流１０と制
限抵抗器ｒｎの両端から取出した零相電圧ＶＯがＤＧＲ
を駆動する入力要素として接続されている。In Figure 6, DGR is a directional ground fault & I electric appliance (hereinafter referred to as DGR) that detects a single-wire ground fault in a line, and GPT is a star-shaped connection of the primary winding, with the neutral point directly grounded. The sex point current In is a charging current based on the capacitance CA-CF of the line that is returned to the system, and the tertiary winding of the GPT is connected in an open delta and is used to detect the zero-sequence voltage ■0. r 1
1 is the limiting resistor (Rn is the value converted to the primary side), Rg is the ground fault resistance at the ground fault point G (an example in the operation explanation), and the zero-sequence current 10 as the secondary side output of the ZCT. The zero-sequence voltage VO taken out from both ends of the limiting resistor rn is DGR.
is connected as an input element to drive.

次にこのような構成の１つの回線において１線地絡発生
時のＤＧＲの保護継電動作について説明する。Next, a description will be given of the protective relay operation of the DGR when a one-line ground fault occurs in one line having such a configuration.

因に、２線以上の地絡、及び２以上の回線の異なる相に
同時に地絡が発生した場合には、短絡故障となり、正常
時と比較して充分に大きな短絡電流が事故回線に発生ず
ることから、通常、図示しない過電流継電器等によって
保護されている。従ってここでは、１線地絡事故のみに
ついて説明する。Incidentally, if a ground fault occurs in two or more lines or in different phases of two or more lines at the same time, a short-circuit failure will occur, and a sufficiently large short-circuit current will occur in the faulty line compared to normal conditions. Therefore, it is usually protected by an overcurrent relay (not shown) or the like. Therefore, only the one-line ground fault accident will be explained here.

尚、１線地絡事故時の様相は第７図に示す等価回路、並
びに第８図のベクトル図によって解析することが可能で
あるが、第７図、及び第８図では、煩雑を避けるため３
回線Ａ−Ｃから成る配電系統で、回線Ａに１線地絡事故
が発生した場合について説明している。ここにＥは対地
電圧で、系統電圧が６．６ｋＶの場合、約３８１０［Ｖ
コとなる。Although it is possible to analyze the situation at the time of a single-line ground fault by using the equivalent circuit shown in Fig. 7 and the vector diagram shown in Fig. 8, in order to avoid complexity, Figs. 3
A case will be described in which a one-line ground fault occurs in line A in a power distribution system consisting of lines A to C. Here, E is the ground voltage, which is approximately 3810 [V when the grid voltage is 6.6 kV.
It becomes Ko.

地絡電流１ｇが地絡事故点（１から地絡抵抗Ｒｇを通し
て大地に流入すると、事故回線のＺＣＴの１次側には電
源側から負荷側（地絡事故点Ｇ側）に向かう故障電流が
流れ、ＺＣＴの２次側出力ｉｔ流として零相電流ＩＡＯ
が得られ、又、健全回線では負荷側から電源側に向かっ
て流れる電流となるので、健全回線のＺＣＴては零相電
流ＩＢＯ１Ｉ　ＣＯが出力されるが、事故回線の零相電
流ＩＡＯと健全回線の零相電流ＩＢＯ１ＩＣＯとでは零
相電流の方向が逆向き、即ち両零相電流ベクトルの位相
が略１８０°異なるものとなっている。又、地絡電流は
ＧＩ’Ｔの中性点から１次巻線に均等に分流するので、
３次巻線の開放デルタ結線により制限抵抗器ｒ　１１の
両端には地絡電流ｒｇの大きさに対応した零相電圧■０
が現われる。When 1 g of ground fault current flows from the ground fault point (1) to the ground through the ground fault resistance Rg, a fault current flows from the power supply side to the load side (earth fault point G side) on the primary side of the ZCT of the fault line. zero-sequence current IAO as the secondary output it flow of ZCT
In addition, in a healthy line, the current flows from the load side to the power supply side, so the ZCT of the healthy line outputs a zero-sequence current IBO1ICO, but the zero-sequence current IAO of the faulty line and the healthy line The direction of the zero-sequence current is opposite to that of the zero-sequence current IBO1ICO, that is, the phases of both zero-sequence current vectors differ by approximately 180°. Also, since the ground fault current is equally divided from the neutral point of GI'T to the primary winding,
Due to the open delta connection of the tertiary winding, a zero-sequence voltage ■0 corresponding to the magnitude of the ground fault current rg is applied to both ends of the limiting resistor r11.
appears.

第８図は零相電圧■０を基準ベクトルとして実軸正方向
にとり、健全回線及び事故回線の電流をベクトルを示す
矢印で示したベクトル図で、健全回線の零相電流は零相
電圧より９０°進んだ虚軸上に在り、地絡電流Ｉ８は全
回線の充電電流と中性点電流Ｉｎのベクトル和として求
められ、事故回線の零相電流は第３象現にあり、健全回
線の零相電流とは略、逆方向であることが判る。Figure 8 is a vector diagram in which the zero-sequence voltage ■0 is taken as a reference vector in the positive direction of the real axis, and the currents in the healthy line and faulty line are shown by arrows indicating the vectors. The ground fault current I8 is found as the vector sum of the charging current of all lines and the neutral point current In, and the zero-sequence current of the failed line is in the third quadrant, and the zero-sequence current of the healthy line is on the advanced imaginary axis. It can be seen that the direction is almost opposite to that of the current.

ＤＧＲは零相電圧■０を基準ベクトルとして零相電流■
０の方向を判定して、それらの積によって動作、不動作
を決定する慄護！！電器で、通常第９図で示される動作
域と不動作域で、ＤＧＲを使用すると高精度且つ高信頼
度の電力形保護継電方式が達成出来るとされている。DGR is the zero-sequence voltage■ Zero-sequence current with 0 as the reference vector■
Determine the direction of 0 and decide whether to move or not by multiplying them! ! In electrical appliances, it is said that a highly accurate and highly reliable power type protective relay system can be achieved by using DGR in the operating range and non-operating range shown in FIG. 9.

〈発明が解決しようとする課題〉 上述のように、従来の非接地系の配電系統にＤＧＲを使
用することは信頼度の高い保護継電方式ではあるが、電
力形の高精度継電器であるＤＧＲはかなり高価であり、
回線数と同数の高価な高級継電器を多分岐開閉装置毎に
設置するのは極めてコスト高となり、叉、ＤＧＲを使用
するとすれば必ず零相電圧ＶＯが必要であるために多分
岐開閉装置毎にＧＰＴを設置し、煩雑な石川電圧■０回
路を１１？４器の周辺に用意する必要があり、継電器周
辺の配線類を輻輳させて信頼度を低下させると共に、よ
り大きな外箱と設置面積を用意する必要があり、大幅な
価格上昇を招き、都市配電の近代化に際しての大きな障
害となっていた。<Problems to be Solved by the Invention> As mentioned above, using DGR in conventional ungrounded power distribution systems is a highly reliable protective relay system, but DGR, which is a power-type high-precision relay, is quite expensive;
Installing the same number of expensive, high-grade relays as the number of lines for each multi-branch switchgear would be extremely costly, and if DGR were to be used, zero-phase voltage VO would be required, so each multi-branch switchgear would need It is necessary to install GPT and prepare a complicated Ishikawa Voltage ■0 circuit around the 11~4 relays, congesting the wiring around the relay and reducing reliability, and requiring a larger outer box and installation space. This led to a significant price increase and was a major obstacle to the modernization of urban electricity distribution.

本発明はこのような障害を除去し、零相電圧ＶＯを利用
せず、従ってＤＧＲやＧＰＴを設置すること無く、零相
電流の相対的方向判定のみによって安価で且つ高信頼度
の１線地絡回線検出を行なう方法を提供することを目的
とするもので、デジタルデータ処理が可能なデジタル方
式の継電装置に適用すると有効である。The present invention eliminates such obstacles and provides a low-cost and highly reliable one-line ground system by only determining the relative direction of the zero-sequence current without using the zero-sequence voltage VO and therefore without installing a DGR or GPT. The purpose of this invention is to provide a method for detecting a faulty circuit, and it is effective when applied to a digital relay device capable of digital data processing.

く課題を解決するための手段〉 １、多分岐開閉装置内に収納された複数の回線中０１つ
の回線に発生する地絡事故の有無を検出する地絡回線検
定方法において、 第１の発明は、前記複数の回線から任意に抽出した第１
の基準回線の零相変流器が出力する零相電流を基準ベク
トルとして、残余の被測定回線の零相変流器が出力する
零相電流ベクトルとの位相差を順次比較計測し、前記基
準回線と前記残余の被測定回線との零相電流位相の間に
、所定の範囲内の差が検出されれば有意差有りと判定し
、前記所定範囲内の差が無ければ有意差無しと判定する
多分岐開閉器装置の地絡回線検定方法であって、若し、
有意差無しと判定した時、当該多分岐開閉器装置の各回
線には１線地絡事故が発生していないと判定し、初期状
態に復帰する手順を備え、若し、有意差有りと判定され
た時には、その回線を事故回線と判定するもので、若し
、基準回線以外の、残余の被測定回線の総てに有意差が
認められた時には、基準回線に１線地絡が存在し、残余
の被測定回線にはｌ線地絡は存在しないと判定して所定
の記憶場所に記憶する手順を設けたものである。Means for Solving the Problem> 1. In a ground fault line verification method for detecting the presence or absence of a ground fault occurring in one line among a plurality of lines housed in a multi-branch switchgear, the first invention provides the following: , the first line arbitrarily extracted from the plurality of lines.
Using the zero-sequence current outputted by the zero-sequence current transformer of the reference line as a reference vector, the phase difference with the zero-sequence current vector outputted by the zero-sequence current transformer of the remaining lines to be measured is sequentially compared and measured, and the If a difference within a predetermined range is detected between the zero-sequence current phases of the line and the remaining line under test, it is determined that there is a significant difference, and if there is no difference within the predetermined range, it is determined that there is no significant difference. A ground fault line verification method for a multi-branch switch device, comprising:
When it is determined that there is no significant difference, it is determined that a single line ground fault has not occurred in each line of the multi-branch switch device, and a procedure is provided to return to the initial state, and if it is determined that there is a significant difference. If a significant difference is found in all of the remaining measured lines other than the reference line, it is determined that there is a one-line ground fault in the reference line. , a procedure is provided for determining that there is no l-line ground fault in the remaining lines under test and storing it in a predetermined storage location.

また、第２の発明は、前記各手順を第１の検定手順とし
、これに加えて、基準回線を変更して同一手順を再実行
する第２の検定を実施するもので、前記基準回線を第１
の基準回線とし、この第１の基準回線以外の任、泣の回
線の中から、更に第２の基準回線を選定抽出して零相電
流の第２の基準ベクトルとして設定し、残余の被測定回
線との零相電流の位相に所定の位相差の有無を再度検定
する手順を備え、前記何意差のある回線があれば、その
回線を第２の所定記憶場所に事故回線候補２として記憶
し、前記第１の検定手順で所定の第１の記憶場所に有意
差ありどして記憶された事故回線候補Ｉと同一の回線で
あることを一致検出手段によって確認して、１線地格事
故の発生した回線の存在を判定し、事故回線と特定する
手順とを設けた。Further, the second invention is to make each of the above-mentioned steps a first verification procedure, and in addition to this, a second verification is carried out in which the same procedure is re-executed by changing the reference line. 1st
The reference line is set as the reference line of A procedure is provided to re-test whether there is a predetermined phase difference in the phase of the zero-sequence current with the line, and if there is a line with the above-mentioned difference, that line is stored in a second predetermined storage location as fault line candidate 2. Then, the coincidence detection means confirms that the line is the same as the accident line candidate I stored in the predetermined first storage location with a significant difference in the first verification procedure, and A procedure has been established to determine the existence of a line where an accident has occurred and identify it as an accident line.

更に、第３の発明は前記第１、第２の発明に対して、各
回線の個々の零相Ｘ流の計測値が、各回線毎に予め設定
された補正値によって補正された値を演算に使用するこ
とを特徴とするものである。Furthermore, a third invention, in contrast to the first and second inventions, calculates a value in which the measured value of each zero-phase X flow of each line is corrected by a correction value set in advance for each line. It is characterized by its use in

つまり、多分岐開閉器装置の回線には地中ケーブルが使
用されるが、電線路のこう長の差やＺＣＴの固有差によ
って各回線での零相電流の位相は健全回線であっても電
気角で２０６乃至３０６バラつくため、位相の比較演算
を行なう前処理段階で、総ての健全回線のプリセットデ
ータとして同一の位相角が付与されるように、実測値を
各回線毎に予め測定して補正値として保存しておき、各
回線の測定値を保存されている補正値で補正して、零相
ｔｔ流の位相の逆転判定の信頼度を高めるものである。In other words, although underground cables are used for the lines of multi-branch switch equipment, the phase of the zero-sequence current in each line may vary due to differences in the length of the electric lines and inherent differences in ZCT, even if the line is in good condition. Since the angle varies by 206 to 306, the actual value is measured for each line in advance so that the same phase angle is given as preset data for all healthy lines in the preprocessing stage when performing phase comparison calculations. The measured value of each line is corrected using the stored correction value, thereby increasing the reliability of determining the phase reversal of the zero-phase tt flow.

く作　用ン 複数（Ｎ）の回線を有する配電系統において、任意に１
つの回線を抽出して第１の基準回線とし、基準回線と残
余の被測定回線（Ｎ−１）との零相電流の同時刻におけ
る位相を順次比較する検定法では、系統中に事故回線が
無い場合は総ての被測定回線（Ｎ−１）について基準回
線と同方向となり、ベクトルとしての位相差０は小さく
、その余弦値ＣＯ５θはほぼ１に近いものとなる。又、
１つの回線に地絡が在る場合には、基準回線が健全回線
であれば、地絡の在る１回線を除いて他の全回線（Ｎ−
２）の零相電流が同方向となるが、事故回線との比較で
は零相電流の方向が逆転するので、ベクトルの位相差０
０余弦値ＣＯ５θは負号となって容易に１つの特定回線
を事故回線として抽出することが出来るが、若し、残余
の全回線（Ｎ−１）の零相電流が総て逆方向となって検
出された場合には、基準回線自身が事故回線であると判
定する。本判定法によれば、多分岐開閉装置の回線数（
Ｎ）にλ１して（Ｎ−１）回の測定結果から判定される
ことになるので、系統の回線数（Ｎ）が充分に大であれ
ば検定の（言頼度は極めて高いものとなる。しかし、回
線数（Ｎ）が小さい場合には検出の信頼度が低下するこ
とが考えられる。In a power distribution system with multiple (N) circuits, one
In the verification method, one line is extracted and used as the first reference line, and the phase of the zero-sequence current at the same time of the reference line and the remaining line to be measured (N-1) is sequentially compared. If there is no such line, all lines to be measured (N-1) will be in the same direction as the reference line, the phase difference 0 as a vector will be small, and its cosine value CO5θ will be close to 1. or,
If there is a ground fault in one line, if the reference line is a healthy line, all other lines (N-
2), the zero-sequence currents are in the same direction, but when compared with the fault line, the direction of the zero-sequence currents is reversed, so the vector phase difference is 0.
The 0 cosine value CO5θ has a negative sign and one specific line can be easily extracted as a failed line, but if the zero-sequence currents of all remaining lines (N-1) are in the opposite direction. If this is detected, the reference line itself is determined to be the fault line. According to this determination method, the number of lines of a multi-branch switchgear (
Since the determination will be made from the results of (N-1) measurements with λ1 for N), if the number of lines in the system (N) is sufficiently large, the reliability of the test will be extremely high However, if the number of lines (N) is small, the reliability of detection may decrease.

第２の発明では、回線数に依存しないで信頼度を向上さ
せるために、前記の各手順に加えて、基準回線を変更し
て再度同一の検定手順を実行するように構成したもので
、第１の基準回線並びに事故回線（吠補ｌ以外の回線か
ら新たに第２の基準回線を設定して、再度、残余の全回
線（Ｎ−１）との零相電流の位相を順次比較する第２の
検定を実行することにより、事故回線候補２が検出され
るので、事故回線候補ｌと事故回線候補２が同一回線で
あることを確認して事故回線を確定する。In the second invention, in order to improve the reliability independent of the number of lines, in addition to the above-mentioned steps, the reference line is changed and the same verification procedure is executed again. A new second reference line is set from the first reference line and the fault line (other than the fault line), and the phase of the zero-sequence current with all remaining lines (N-1) is sequentially compared again. By executing the test No. 2, faulty line candidate 2 is detected, so it is confirmed that faulty line candidate 1 and faulty line candidate 2 are the same line, and the faulty line is determined.

多分岐開閉装置では一般に地中ケーブルが使用され、ケ
ーブルのこう長、負荷の種類等によっては健全回線であ
っても、各回線の零相電流には同時にサンプリングを行
なって計測しても例えば位相角で２０°〜３０°の差が
最初から認められることがあるが、第３の発明では夫々
の健全時のデータに基づくプリセットデータに補正され
ているので、期間の位相角は総て揃っていると見なすこ
とが可能となり、基準回線が任意に通訳され、設定され
ても位相差の測定を同相であれば０°、逆相であれば１
８０”と判定のアルゴリズムを単純化することが出来、
判定の信頼度が向上する。Underground cables are generally used in multi-branch switchgear, and depending on the length of the cable, type of load, etc., even if the line is sound, the zero-sequence current of each line may be sampled and measured at the same time. A difference of 20° to 30° in angle may be recognized from the beginning, but in the third invention, since it is corrected to the preset data based on the data at each healthy time, the phase angles of the periods are all the same. Even if the reference line is arbitrarily interpreted and set, the phase difference measurement will be 0° if it is in phase and 1 if it is out of phase.
80” and the algorithm for determination can be simplified,
The reliability of judgment is improved.

〈実施例〉 以下、本発明をデジタル処理群？に装置として実施した
その一実施例を示す第１図乃至第３図に基づいて説明す
る。<Example> Hereinafter, the present invention will be referred to as a digital processing group? An embodiment of the present invention implemented as a device will be explained based on FIGS. 1 to 3, which show an embodiment of the present invention.

ここに、第１図は本発明の第１の発明の−実施例に係わ
る多分岐開閉装置の地絡回線検定方法の判定手順を示す
フローチャート、第２図は本発明の第２の発明の一実施
例に係る多分岐開閉装置の地絡回線検定方法の判定手順
を示すフローチャート、第３図は本発明の一実施例に係
わる多分岐開閉装置のデジタル処理継電装置の信号伝達
経路を示すブロック図、第４図は各回線の零相電流を、
夫々の回線に設置されているＺＣＴ２次出力電流のベク
トルとして同時計測した時に得られる順方向、逆方向の
概念図で、横行に回線Ａから回線Ｆの中で基準となる回
線上を示し、縦列方向にはどの回線に１線地絡事故が発
生したかを示している。Here, FIG. 1 is a flowchart showing the determination procedure of the ground fault line verification method for a multi-branch switchgear according to the embodiment of the first invention of the present invention, and FIG. A flowchart showing the determination procedure of a ground fault line verification method for a multi-branch switchgear according to an embodiment, and FIG. 3 is a block diagram showing a signal transmission path of a digital processing relay device for a multi-branch switchgear according to an embodiment of the present invention. Figure 4 shows the zero-sequence current of each line,
This is a conceptual diagram of the forward and reverse directions obtained when simultaneously measuring the ZCT secondary output current installed in each line as a vector.The horizontal line shows the reference line from line A to line F, and the vertical line shows the reference line from line A to line F. The direction indicates in which line the single-line ground fault occurred.

以下の説明中、第５図〜第９図に示した従来装置の構成
要素と共通の要素には同一の符号を使用し、重複を避け
るため、詳細な説明を省略し、異なる要素についてのみ
説明する。In the following explanation, the same reference numerals will be used for elements common to those of the conventional device shown in Figs. 5 to 9, detailed explanations will be omitted to avoid duplication, and only different elements will be explained. do.

第３図（イ）はデジタル処理継電装置のＡ／Ｄ変換部の
構成を示すもので、各回線Ａ−ＦのＺＣＴからの出力信
号へ“〜Ｆ゛が補助変成器ＡＸＴを経由してＡ／Ｄ変換
部に入力され、フィルターＦによって高域成分を除去し
た後、サンプルホールｌ”ＳＮ、マルチプレクサＭＰＸ
両回路を経てＡ／Ｄ変換回路によってデジタルデータに
変換されて次段の演算部に処理が移動する。Figure 3 (A) shows the configuration of the A/D conversion section of the digital processing relay device, in which the output signal from the ZCT of each line A-F is sent via the auxiliary transformer AXT. It is input to the A/D converter, and after removing high-frequency components by filter F, it is sent to sample hole l”SN and multiplexer MPX.
After passing through both circuits, the data is converted into digital data by an A/D conversion circuit, and the processing is transferred to the next stage arithmetic unit.

演算部は第３図（０）に示されるようにマイクロプロセ
ッサＣＩ）Ｕを中心にプログラムを収納する読出し専用
記憶回路ＲＯＭ、継電器の整定値を設定、記憶する回路
ＳＥＴ、作業用の読み書き可能な記憶回路ＲＡＭ、次段
の操作部とデジタル信号を送受信するためのインターフ
ェース回路ＩＦ、１ｉ報、表示、記録のためのバッファ
ー回路［３１，Ｉ　Ｆ等を信号バスＢＵＳで結んだ回路
構成となっている。As shown in Figure 3 (0), the arithmetic unit includes a microprocessor CI)U, a read-only memory circuit ROM that stores programs, a circuit SET that sets and stores the setting values of the relay, and a read/write circuit for working. The circuit has a memory circuit RAM, an interface circuit IF for transmitting and receiving digital signals with the next stage operation section, a buffer circuit for 1i information, display, and recording [31, IF, etc. are connected by a signal bus BUS. There is.

このような構成のデジタル処理装置では一般に入力され
たアナログ頃（正弦波）を一定周期でサンプリングした
値を演算処理しており、多くの演算方式が適用されてい
るが、ここでは、最も代表的な例としてデジタル処理の
継電装置によく適用されている積和方式によって説明す
る。Digital processing devices with this type of configuration generally process values obtained by sampling input analog waves (sine waves) at regular intervals, and many calculation methods are applied, but here we will introduce the most typical one. As an example, the sum-of-products method, which is often applied to digital processing relay devices, will be explained.

今、回線Ａ及び回線Ｂに装着されている零相変流器ＺＣ
Ｔの２次出力電流を夫々ＩＡＯ，ＩＢＯとし、ＩＡＯと
ＩＢＯとは位相角の差がθであるとすると、これらを時
間ｔでサンプリングした値どうし、及び３サンプリング
前のデータどうしの積を作って加算したものは、 （ＩＡＯ（＋、））　・（ｌ　ＢＯ（量、））＋（ＩＡ
Ｏ（ｔ−３ｈ））　・（１８０（ｔ−３ｈ））＝ＩＡＯ
・１８０・ＣＯ５θ・・・・・・・・・・・・・・（１
）となる。Zero-phase current transformer ZC currently installed on line A and line B
Assuming that the secondary output currents of T are IAO and IBO, respectively, and the difference in phase angle between IAO and IBO is θ, the products of these values sampled at time t and the data three samplings ago are created. What is added is (IAO(+,)) ・(l BO(amount, ))+(IA
O(t-3h)) ・(180(t-3h))=IAO
・180・CO5θ・・・・・・・・・・・・・(1
).

ここに、ＩＡＯ（ｔ−３ｈ）はＩＡＯ（ｆ、）から３サ
ンプリング前のデータを示し、又、ｈはサンプリング時
間幅で通常電気角３０°になるように設定される。Here, IAO(t-3h) indicates data three samplings ago from IAO(f,), and h is the sampling time width, which is usually set to be an electrical angle of 30 degrees.

具体的には、回線へと回線ＢのＺＣＴ二次出力は各サン
プリング時間毎に瞬時値が計測され、デジタル処理され
て記憶回路ＲＡＭの夫々の所定場所に一時記憶され、更
に積演算の結果、３サンプリング時間前のデータとの和
演算結果も記憶回路ＲＡＭに記録され、必要に応じて読
出と書込が行なわれている。Specifically, the instantaneous value of the ZCT secondary output of the line B to the line is measured at each sampling time, digitally processed and temporarily stored in each predetermined location of the memory circuit RAM, and as a result of the product operation, The result of the sum operation with the data three sampling times before is also recorded in the storage circuit RAM, and read and written as necessary.

この（１）式の左辺は入力する零相電流の瞬時値からな
るデータであるが、右辺は時間成分を含まない定数で、
θが定まればｃｏｓ　ｏの値が定まり、θが１８０°変
化すれば、式の値はその符号の正負が逆転することを示
しており、この積和演算の過程で容易に２つの零相電流
間の位相比較を行な・うことが可能である。このため、
以下、各回線から人力される零相電流の基準回線の零相
電流に対する位相差の比較は総て上記のＴ、ｒ［ｉ１１
方式によるものとして、次に本発明のうち、第１の発明
における地絡回線検定方法の判定手順の実施例について
第１図を参照して説明する。尚、第１図に示すフローチ
ャートの説明中、５１．５２・・・・・は処理手順（ス
テップ）の番号を示す。The left side of equation (1) is data consisting of the instantaneous value of the input zero-sequence current, but the right side is a constant that does not include a time component.
If θ is determined, the value of cos o is determined, and if θ changes by 180°, the sign of the value of the equation will be reversed, and in the process of this product-sum operation, two zero phases can easily be obtained. It is possible to perform phase comparisons between currents. For this reason,
Below, the comparison of the phase difference of the zero-sequence current manually inputted from each line with respect to the zero-sequence current of the reference line is based on the above T, r[i11
Next, an embodiment of the determination procedure of the ground fault line verification method according to the first aspect of the present invention will be described with reference to FIG. 1. In the description of the flowchart shown in FIG. 1, 51, 52, . . . indicate processing procedure (step) numbers.

零相電流間の位相比較がスタートすると、Ｓｌで先ず全
体（Ｎ）の回線から１つの基準回線が選択されるため、
第１の基準回線を設定するサブルーチンが実行される。When the phase comparison between zero-sequence currents starts, one reference line is first selected from the total (N) lines in Sl, so
A subroutine for setting a first reference line is executed.

具体的には、Ａ−Ｆの６回線から例えば入回線が基準回
線として選択される。Ｓｌては回線Ａ−Ｆに装着された
ＺＣＴの２次側出力Ａ゛〜Ｆ°からＩｌ［ｉ次零相電流
ＩＡＯ〜ＩＦＯを計測し、ＩＡＯを基準とした（１）式
に示した積和演算が実行され、Ｓ３ではその値が正数で
あれば有意差無し、負であれば有意差有りとして演算結
果の値を正負の符号別に分類して、Ｓ４で夫々の個数１
１が計数される。若し、積和演算結果が負数となった回
線数がｎ＝１ならその１つの回線の零相電流の方向が基
準回線の零相電流に対して逆向きであることを示してお
り、その１つの回線が事故回線であると判定する。Specifically, for example, an incoming line is selected from the six lines A to F as the reference line. Sl is the product obtained by measuring the i-order zero-sequence currents IAO to IFO from the secondary outputs A゛~F° of the ZCT installed in the line A-F, and calculating the product shown in equation (1) with IAO as the reference. The sum operation is executed, and in S3, if the value is a positive number, there is no significant difference, and if the value is negative, there is a significant difference.The values of the operation result are classified according to positive and negative signs, and in S4, each number is 1.
1 is counted. If the number of lines for which the product-sum calculation result is a negative number is n = 1, this indicates that the direction of the zero-sequence current of that one line is opposite to the zero-sequence current of the reference line. One line is determined to be an accident line.

また、積和演算結果が負数となった回線数がｎ＝Ｎ　−
１即ち５であれば、基準回線となった入回線が事故回線
と判定される。Also, the number of lines for which the sum of products operation result is a negative number is n=N −
If it is 1, that is, 5, the incoming line that has become the reference line is determined to be the faulty line.

第２図は本発明の第２の発明に係わる判定手順の一実施
例を示すフローチャートで、第１の発明で説明した５１
〜Ｓ６の判定手順を実行した後、例えば８回線のみが零
相電流の位相が有意差が検出されたとするとｎ＝Ｉであ
るから１次段の５７に移行するが、Ｓ７で直ちに事故回
線の判定を下す事なく、Ｓ７では事故回線候補ｌとして
の判定が行なわれ、Ｓ８で記憶領域の所定番地に回線名
の記号Ｂが記憶１として書き込まれる。FIG. 2 is a flowchart showing an embodiment of the determination procedure according to the second invention of the present invention.
After executing the determination procedure in ~S6, for example, if a significant difference in the phase of the zero-sequence current is detected in only 8 lines, the process moves to the primary stage 57 because n=I, but immediately in S7, the phase of the faulty line is detected. Without making a determination, in S7 it is determined that the line is the failed line candidate 1, and in S8 the symbol B of the line name is written as memory 1 at a predetermined location in the storage area.

この時、若し、ｎ：Ｎ−１＝５であれば、Ｂ−Ｆの回線
総てが有意差有りとなったことから、基準回線の入回線
自身が事故回線である可能性が高い。しかし、この段階
では入回線が事故回線と断定せず、Ｓ７で回線名の記号
へを事故回線候補１として設定し、Ｓ８て所定の記憶領
域に記憶ｌとして書き込まれる。At this time, if n:N-1=5, all the lines of B-F have significant differences, so there is a high possibility that the incoming line of the reference line itself is the failed line. However, at this stage, the incoming line is not determined to be the faulty line, and the line name symbol is set as faulty line candidate 1 in S7, and is written as memory 1 in a predetermined storage area in S8.

次の５９で、基準回線を変更して再設定しているが、こ
の時には最初の基準回線である入回線並びに事故回線候
補ｌの８回線は対象から除外され、第２の基準回線とは
ならないので、５１０で位相比較を行なえば、有意差の
ある回線は１つだけ検出される。In the next step 59, the reference line is changed and reconfigured, but at this time, the first reference line, the incoming line, and the 8 fault line candidate lines are excluded from the target and do not become the second reference line. Therefore, if phase comparison is performed in step 510, only one line with a significant difference will be detected.

即ち、８回線が事故回線の場合には、入回線、６回線以
外の４回線から例えば回線Ｃを第２の基準回線として選
択設定して、残余の回線との位相比較を行なうことにな
り、又、入回線が事故回線であった場合には入回線を除
いた残余の５回線から第２の基準回線が、例えば回線Ｂ
が選択され、何れの場合も、事故回線の零相電流の方向
が基準回線のそれと逆転していることが確認される。こ
の結果、５１２では事故回線候補２が決定され、Ｓ１３
て所定の記憶場所に記憶２として記憶されるので、次の
５１４において記憶ｌ、記憶２の読出しを行い、５１５
で事故回線候補ｌと事故回線候補２とが同一回線である
ことを確認することによって事故回線の判別が終了する
。That is, if line 8 is the failed line, for example, line C is selected and set as the second reference line from the 4 lines other than the incoming line and line 6, and phase comparison with the remaining lines is performed. In addition, if the incoming line is the faulty line, the second reference line from the remaining five lines excluding the incoming line is, for example, line B.
is selected, and in either case, it is confirmed that the direction of the zero-sequence current of the failed line is reversed from that of the reference line. As a result, fault line candidate 2 is determined in 512, and S13
Since it is stored as memory 2 in a predetermined memory location, the memory 1 and memory 2 are read in the next step 514, and the memory 2 is read out in 515.
By confirming that the failed line candidate 1 and the failed line candidate 2 are the same line, the determination of the failed line is completed.

次に、第３の発明の実施例としては、前記第１、第２の
発明の実施例おいて各回線のＺＣＴの一次側に予め定め
られた試験用電流を同時に通電し、各２６１間の射そう
特性を演算部（第３図（ロ）参照）のＲＡＭに位相特性
値として格納しておく。そして、実際の事故回線の検定
時には、これらの格納された位相特性値で各ＺＣＴの出
力を補正すれば、各ＺＣＴの先天的な位相特性差を無視
することが可能となる。Next, as an embodiment of the third invention, in the embodiments of the first and second inventions, a predetermined test current is simultaneously applied to the primary side of the ZCT of each line, and the The characteristics that are likely to be projected are stored in the RAM of the arithmetic unit (see FIG. 3 (b)) as phase characteristic values. Then, when actually verifying a faulty line, by correcting the output of each ZCT using these stored phase characteristic values, it becomes possible to ignore the inherent phase characteristic difference of each ZCT.

〈発明の効果〉 本発明を適用した多分岐開閉器装置は、零相変流器の二
次出力電流のベクトル比較を各回線間で実行するだけで
１線地絡事故が発生した事故回線の検出が可能となるの
で、高価な高精度リレーであるＤＧＲを回線毎に設置す
る必要が無く、又、多分岐開閉器装置の箱毎にＧＰＴを
設置する必要も無くなり、従って継電器周辺の煩雑な零
相電圧ＶＯ量関係配線も無くなり、すっきりと纒めるこ
とが出来るので、多分岐開閉器装置の占有面積を大幅に
縮小することが可能となり、製品原価の低減に寄与する
と共に、その縮小効果によって、都市配電の近代化に必
要な簡素な構成となり、都市での設置コストの上昇を抑
制するに極めて有効である。<Effects of the Invention> The multi-branch switch device to which the present invention is applied can eliminate faulty lines in which single-line ground faults have occurred by simply performing vector comparison of the secondary output currents of zero-phase current transformers between each line. Since detection becomes possible, there is no need to install DGR, which is an expensive high-precision relay, on each line, and there is no need to install GPT on each box of a multi-branch switch device, thus eliminating the need for complicated areas around relays. Zero-phase voltage VO amount-related wiring is also eliminated and can be summarized clearly, making it possible to significantly reduce the area occupied by the multi-branch switch device, contributing to a reduction in product cost and the reduction effect. This provides a simple configuration necessary for modernizing urban power distribution, and is extremely effective in suppressing increases in installation costs in cities.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は多分岐開閉装置の地絡回線検定方法に係わる第
１の発明の判定手順を示すフローチャート、第２図は多
分岐開閉装置の地絡回線検定装置方法に係わる第２の発
明の判定手順を示すフローチャート、第３図は多分岐開
閉装置の地絡回線検定装置に係わる第３の発明のデジタ
ル処理継電装置の信号伝達経路を示すブロック図、第４
図は多分岐開閉装置の各零相変流器の出力電流ベクトル
の概念図、第５図は多分岐開閉装置の構成概要図、第６
図は、回線１回線分の構成図、第７図は３回線系統の等
価回路図、第８図は零相電流のベクトル図、第９図は方
向地絡継電器ＤＧＲの動作特性図。 ３０・・電源　　　　　３１・・主変圧器３２・・高圧
母線　　　３３・・零相変流器ＺＣＴ３４・・接地形計
器用変圧器ＧＰＴ ３５・・限流抵抗器Ｒｎ３６・・地絡抵抗Ｒｇ３７拳 事故点 方向地絡継電器ＤＧＲ ２− ・遮断器ＣＢ Ｓ　ｌ〜Ｓ ・フローチャートのステップ番号FIG. 1 is a flowchart showing the determination procedure of the first invention related to the ground fault line verification method for multi-branch switchgear, and FIG. 2 is a flowchart showing the determination procedure of the second invention related to the ground fault line verification method for multi-branch switchgear. Flowchart showing the procedure, FIG. 3 is a block diagram showing the signal transmission path of the digital processing relay device of the third invention related to the ground fault line verification device of the multi-branch switchgear, and FIG.
The figure is a conceptual diagram of the output current vector of each zero-phase current transformer of the multi-branch switchgear, Figure 5 is a schematic diagram of the configuration of the multi-branch switchgear, and Figure 6 is a schematic diagram of the configuration of the multi-branch switchgear.
7 is an equivalent circuit diagram of a three-line system, FIG. 8 is a vector diagram of zero-sequence current, and FIG. 9 is an operating characteristic diagram of a directional ground fault relay DGR. 30...Power supply 31...Main transformer 32...High voltage bus 33...Zero phase current transformer ZCT34...Grounding instrument transformer GPT 35...Current limiting resistor Rn36...Ground fault resistance Rg37 Fault point Directional ground fault relay DGR 2- - Breaker CB S l~S - Flowchart step number

Claims (3)

【特許請求の範囲】[Claims] （１）多分岐開閉装置内に収納された複数の回線から任
意に抽出した基準回線の零相変流器が出力する零相電流
を基準ベクトルとする基準回線設定手順と、 前記基準ベクトルと、前記複数の、回線から前記基準回
線を除外した残余の被測定回線の零相変流器が出力する
零相電流のベクトルとの、同時刻における位相差を順次
計測して前記基準ベクトルと比較する位相比較手順と、 前記基準ベクトルと前記残余の被測定回線の零相電流の
ベクトルとの位相に所定範囲内の差があるとき有意差あ
り、所定範囲内の差がないとき有意差なしと判定する有
意差判定手順と、 有意差なしと判定したとき初期状態に復帰する復帰手順
と、 有意差ありと判定したとき、その有意差を示す回線数が
、１つの回線か、残余の被測定回線の全回線かを判定し
、１つの回線のときは当該回線を、残余の全回線のとき
は前記基準回線を、夫々に事故回線として所定の記憶場
所に記憶する、事故回線判定手順、 を具備したことを特徴とする多分岐閉閉装置の地絡回線
検定方法。(1) A reference line setting procedure in which a zero-sequence current output by a zero-sequence current transformer of a reference line arbitrarily extracted from a plurality of lines housed in a multi-branch switchgear is used as a reference vector, and the reference vector; Sequentially measuring the phase difference at the same time with a zero-sequence current vector output from a zero-sequence current transformer of the remaining lines to be measured after excluding the reference line from the plurality of lines, and comparing the phase differences with the reference vector. Phase comparison procedure; When there is a difference in phase between the reference vector and the zero-sequence current vector of the remaining line to be measured within a predetermined range, it is determined that there is a significant difference, and when there is no difference within a predetermined range, it is determined that there is no significant difference. A recovery procedure that returns to the initial state when it is determined that there is no significant difference, and a return procedure that returns to the initial state when it is determined that there is no significant difference. A failure line determination procedure is provided, which determines whether all of the remaining lines are the same, and stores that line in a predetermined storage location as a failure line, and stores the reference line in a predetermined storage location if it is one line, and if all the remaining lines are the failure lines. A ground fault line verification method for a multi-branch closure device. （２）多分岐開閉装置内に収納された複数の回線から任
意に抽出した第１の基準回線の零相変流器が出力する零
相電流を第１の基準ベクトルとする基準回線設定手順と
、 前記第１の基準ベクトルと、前記複数の回線から前記第
１の基準回線を除外した残余の被測定回線の零相変流器
が出力する零相電流のベクトルの位相差を順次計測して
前記第１の基準ベクトルと比較する第１の位相比較手順
と、 前記第１の基準ベクトルと前記残余の被測定回線の零相
電流のベクトルとの位相に、所定範囲内の差があるとき
有意差あり、所定範囲内の差がないとき有意差なしと判
定する第１の有意差判定手順と、 有意差なしと判定したとき初期状態に復帰する第１の復
帰手順と、 有意差ありと判定したとき、それが１つの回線か残余の
被測定回線の全回線かを判定し、１つの回線のときは当
該回線を、残余の全回線のときは前記第１の基準回線を
事故回線候補１として所定の記憶場所に記憶する第１の
事故回線候補判定手順と、 前記第１の基準回線以外の、任意の回線から抽出した第
２の基準回線の零相変流器が出力する零相電流を第２の
基準ベクトルとする第２の基準回線設定手順と、 前記第２の基準ベクトルと前記残余の被測定回線の零相
電流のベクトルとの位相に所定範囲内の差があるとき有
意差あり、所定範囲内の差がないとき有意差なしと判定
する第２の有意差判定手順と、 有意差なしと判定したときには初期状態に復帰する第２
の復帰手順と、 有意差ありと判定したときは、その回線を事故回線候補
２として所定の記憶場所に記憶する第２の事故回線候補
判定手順と、 前記第１の事故回線候補判定手順で事故回線候補１とし
て記憶された回線と、前記第２の事故回線候補判定手順
で記憶された事故回線候補２が同一回線か、否かを判定
する一致検出手順と、同一回線のとき当該回線を事故回
線と決定する手順と、 同一回線でないと判定したとき初期状態に復帰する第３
の復帰手順と、 を具備したことを特徴とする多分岐開閉装置の地絡回線
検定方法。(2) A reference line setting procedure in which the zero-sequence current output by the zero-sequence current transformer of the first reference line arbitrarily extracted from the plurality of lines housed in the multi-branch switchgear is used as the first reference vector; , Sequentially measuring the phase difference between the first reference vector and the zero-sequence current vector output by the zero-sequence current transformer of the remaining measured line after excluding the first reference line from the plurality of lines; a first phase comparison procedure for comparing with the first reference vector; and significant when there is a difference within a predetermined range in phase between the first reference vector and the vector of the zero-sequence current of the remaining line under test. A first significant difference determination procedure that determines that there is a difference and that there is no significant difference when there is no difference within a predetermined range; A first restoration procedure that returns to the initial state when it is determined that there is no significant difference; When this happens, it is determined whether it is one line or all of the remaining lines under test, and if it is one line, the line is selected, and if it is all the remaining lines, the first reference line is selected as fault line candidate 1. a first fault line candidate determination procedure for storing in a predetermined storage location as a zero-sequence current output by a zero-sequence current transformer of a second reference line extracted from an arbitrary line other than the first reference line; a second reference line setting procedure in which the second reference vector is a second reference vector; and a significant difference when there is a difference within a predetermined range in phase between the second reference vector and the zero-sequence current vector of the remaining measured line. A second significant difference determination procedure that determines that there is no significant difference when there is no difference within a predetermined range, and a second significant difference determination procedure that returns to the initial state when it is determined that there is no significant difference.
A second fault line candidate determination procedure that stores the line as fault line candidate 2 in a predetermined storage location when it is determined that there is a significant difference; A match detection procedure for determining whether or not the line stored as line candidate 1 and the fault line candidate 2 stored in the second fault line candidate determination procedure are the same line; The procedure for determining that the lines are the same, and the third step that returns to the initial state when it is determined that they are not the same line.
A ground fault line verification method for a multi-branch switchgear, characterized by comprising a recovery procedure and the following. （３）各回線個々の零相電流の位相判定に使用する位相
角の値が各回線毎に、予め設定された補正値によって補
正された値で置換されることを特徴とする請求項第１項
または請求項第２項記載の多分岐開閉装置の地絡回線検
定方法。(3) Claim 1, characterized in that the value of the phase angle used to determine the phase of the zero-sequence current for each line is replaced with a value corrected by a preset correction value for each line. A ground fault line verification method for a multi-branch switchgear according to claim 2 or claim 2.