JPH11215688A - Grounding detector for distribution system, and power receiving and distributing facility using the grounding detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect the grounding accident on the side of high-voltage distribution cable, with the circuit on low voltage side of a transformer for power reception, by detecting the reverse-phase components of the fundamental wave of a three-phase AC current detected with a three-phase AC detector, and judging the existence of the occurrence of the grounding accident from this reverse-phase components. SOLUTION: When it is judged that a grounding accident has occurred in any of high-voltage distribution cables 3a-3c by grounding judgers provided at network protectors 4Ga-4Gc, breaker controller 4Ea-4Ec give breakers 4Da-4Dc breaking commands. For example, when the high-voltage distribution cable 3a is cut off the bus 1B1 of a substation 1, the protector breaker 4Da opens to cut off the circuit on high voltage side and the circuit on low voltage side of the transformer 4Ba from each other because the grounding judger of the breaker controller 4Ea detects a grounding accident occurring in the high-voltage cable 3a. As a result, this system can prevent the tidal current of reverse power from occurring on the side of high-voltage distribution cable 3a from side of other sound distribution cables 3a and 3c.

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【０００１】[0001]

【発明の属する技術分野】本発明は、受配電設備で高圧
配電線の地絡事故を検出するために用いる地絡検出装
置、及び該地絡検出装置を用いた受配電設備に関するも
のである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ground fault detecting device used for detecting a ground fault of a high voltage distribution line in a power receiving and distribution facility, and to a power receiving and distribution facility using the ground fault detecting device.

【０００２】[0002]

【従来の技術】配電系統においては、電源変電所から引
き出された複数の高圧配電線にネットワーク受配電設備
や常用予備受配電設備などの様々な受配電設備が接続さ
れている。また最近では、配電系統に、自家発電設備や
太陽光発電設備などの分散型電源が接続されるため、該
分散型電源を配電系統と連系させることが必要になって
いる。2. Description of the Related Art In a power distribution system, various power receiving and distribution facilities such as a network power receiving and distribution facility and a regular standby power receiving and distribution facility are connected to a plurality of high-voltage distribution lines drawn from a power substation. Recently, since a distributed power supply such as a private power generation facility or a solar power generation facility is connected to the distribution system, it is necessary to connect the distributed power supply to the distribution system.

【０００３】配電系統において、いずれかの高圧配電線
で地絡事故が発生した場合には、電源変電所の変圧器と
事故が生じた高圧配電線との間に設けられた遮断器に遮
断動作を行なわせて、地絡事故が生じた高圧配電線を電
源変電所の変圧器から切り離すようにしている。[0003] In the distribution system, if a ground fault occurs in any one of the high-voltage distribution lines, a breaking operation is performed by a circuit breaker provided between the transformer of the power substation and the high-voltage distribution line in which the accident has occurred. To disconnect the high-voltage distribution line in which the ground fault occurred from the transformer of the power substation.

【０００４】地絡事故が生じた場合には、事故が生じた
高圧配電線を直ちに無電圧状態として、その事故の復旧
作業を行う必要がある。ところが、配電系統にネットワ
ーク受配電設備が設けられている場合には、複数の高圧
配電線の間がネットワーク受配電設備内の回路を通して
相互に接続されるため、事故が発生した高圧配電線を電
源変電所の変圧器から切り離しても、他の健全な高圧配
電線からネットワーク変圧器を通して、事故が発生した
高圧配電線に逆電力の潮流が起る。[0004] When a ground fault occurs, it is necessary to immediately restore the high-voltage distribution line in which the accident has occurred to a no-voltage state, and to perform a recovery operation for the accident. However, if the distribution system is provided with network power distribution equipment, multiple high-voltage distribution lines are interconnected through circuits in the network power distribution equipment. Even if it is disconnected from the transformer at the substation, reverse power flows from the other healthy high-voltage distribution lines through the network transformer to the high-voltage distribution line where the accident occurred.

【０００５】ネットワーク受配電設備では、事故が生じ
た配電線につながるネットワーク変圧器（受電用変圧
器）の励磁電流と事故が生じた配電線の対地静電容量を
通して流れる充電電流との合成電流から逆電力の潮流が
生じたことを、各ネットワーク変圧器の低圧側で検出す
るネットワーク継電器を各ネットワーク変圧器に対して
設けて、該ネットワーク継電器により所定の位相、及び
しきい値以上の逆電力の潮流が検出されたときに、ネッ
トワーク変圧器の低圧側に設けられたプロテクタ遮断器
を開くことにより、直ちにその回線を事故が生じた高圧
配電線から切り離して逆電力の潮流を遮断するようにし
ている。[0005] In the network power receiving and distribution equipment, the combined current of the excitation current of the network transformer (power receiving transformer) connected to the distribution line in which the accident has occurred and the charging current flowing through the earth capacitance of the distribution line in which the accident has occurred. A network relay for detecting the occurrence of the reverse power flow on the low voltage side of each network transformer is provided for each network transformer, and the network relay has a predetermined phase and a reverse power of a threshold value or more. When a power flow is detected, open the protector circuit breaker provided on the low voltage side of the network transformer, immediately disconnect the line from the high-voltage distribution line in which the accident occurred, and cut off the reverse power flow. I have.

【０００６】[0006]

【発明が解決しようとする課題】ネットワーク受配電設
備や常用予備受配電設備などの各種の受配電設備が設け
られている配電系統に分散型電源が連系している場合に
は、系統の負荷バランス状態や分散型電源の発電状態等
の系統条件によって電力の潮流状況が複雑に変わり、地
絡事故の発生がない定常状態でも、ネットワーク受配電
設備のネットワーク母線側からネットワーク変圧器を通
して高圧配電線側に逆電力の潮流が起ることがある。こ
のような定常時の逆電力の潮流に応答してネットワーク
受配電設備内の遮断器が遮断動作を行なうことは避ける
必要があるため、系統に分散型電源が連系している場合
等の、逆電力の潮流が発生し易い系統条件の下では、ネ
ットワーク受配電設備内で逆電力の潮流を検出している
継電器のしきい値を高く設定して、該受配電設備内のプ
ロテクタ遮断器の遮断動作に抑制をかける必要がある。When a distributed power supply is interconnected to a distribution system provided with various power receiving and distribution facilities such as a network power receiving and distribution facility and a regular standby power distribution facility, the load on the system is increased. The power flow situation changes in a complicated manner depending on the system conditions such as the balance state and the power generation state of the distributed power supply, and even in a steady state where no ground fault occurs, the high-voltage distribution line from the network bus side of the network power receiving and distribution equipment through the network transformer Reverse power flow may occur on the side. Since it is necessary to avoid that the circuit breaker in the network power receiving and distribution equipment performs the breaking operation in response to the flow of the reverse power in the steady state, such as when the distributed power supply is connected to the system, Under system conditions in which reverse power flow is likely to occur, the threshold value of the relay that detects reverse power flow in the network power receiving and distribution equipment is set high, and the protector breaker in the power receiving and distribution equipment is set to a high value. It is necessary to control the shutoff operation.

【０００７】ところが、高圧配電線側で地絡事故が発生
して変電所側の遮断器が開いたときに、ネットワーク変
圧器の励磁電流と高圧配電線の対地静電容量を通して流
れる充電電流との合成電流は極めて小さいため、各ネッ
トワーク受配電設備内の逆電力検出用の継電器のしきい
値を高く設定すると、高圧配電線で地絡事故が発生した
ときに生じる逆電力の潮流を検出できなくなり、事故が
生じた高圧配電線につながるネットワーク受配電設備内
の回線を高圧配電線から切り離すことができなくなる。
その結果、他の健全な高圧配電線から事故が生じた高圧
配電線に給電され続けることになり、事故の復旧のため
の点検、修理作業等を行なうことができなくなる。However, when a ground fault occurs on the high-voltage distribution line side and the circuit breaker on the substation side opens, the excitation current of the network transformer and the charging current flowing through the earth capacitance of the high-voltage distribution line are reduced. Since the combined current is extremely small, if the threshold value of the reverse power detection relay in each network power receiving and distribution equipment is set high, it will not be possible to detect the reverse power flow that occurs when a ground fault occurs in the high-voltage distribution line. In addition, the line in the network power distribution equipment connected to the high-voltage distribution line in which the accident occurred cannot be separated from the high-voltage distribution line.
As a result, power is continuously supplied from another healthy high-voltage distribution line to the high-voltage distribution line in which the accident has occurred, and it becomes impossible to perform inspection, repair work, and the like for restoration of the accident.

【０００８】上記のような事態を避けるためには、ネッ
トワーク受配電設備内に高圧配電線の地絡事故を検出す
る地絡検出装置を設けて、該地絡検出装置が地絡を検出
した時に直ちにネットワーク変圧器に直列に接続されて
いるプロテクタ遮断器を開いて、事故が生じた高圧配電
線につながるネットワーク受配電設備内の回線を該高圧
配電線から切り離すことができるようにしておく必要が
ある。In order to avoid the above-mentioned situation, a ground fault detecting device for detecting a ground fault of a high voltage distribution line is provided in the network power receiving and distributing facility, and when the ground fault detecting device detects the ground fault, It is necessary to immediately open the protector circuit breaker connected in series with the network transformer so that the line in the network power distribution system leading to the high-voltage distribution line where the accident has occurred can be disconnected from the high-voltage distribution line. is there.

【０００９】配電系統で従来から用いられている地絡検
出装置は、零相変流器を用いて地絡事故発生時に流れる
零相分を検出するようにしたものが多く、該地絡検出装
置によりネットワーク受配電設備内で高圧配電線の地絡
事故を検出するためには、ネットワーク変圧器の高圧側
の回路に地絡検出装置を接続する必要がある。[0009] Many ground fault detecting devices conventionally used in power distribution systems detect a zero-phase component flowing when a ground fault occurs using a zero-phase current transformer. Therefore, in order to detect a ground fault of a high voltage distribution line in a network power receiving and distribution facility, it is necessary to connect a ground fault detecting device to a circuit on a high voltage side of the network transformer.

【００１０】ところが、ネットワーク変圧器の高圧側の
回路には高い電圧が印加されているため、この回路に零
相変流器などの検出器を取り付けることは好ましくな
い。またネットワーク受配電設備では、ネットワーク変
圧器と高圧配電線との間の構成をできるだけ簡素にした
いとの要請があるため、ネットワーク変圧器の高圧側の
回路に余計な装置を接続することは避ける必要がある。However, since a high voltage is applied to the circuit on the high voltage side of the network transformer, it is not preferable to attach a detector such as a zero-phase current transformer to this circuit. In network power receiving and distribution equipment, there is a demand to make the configuration between the network transformer and the high-voltage distribution line as simple as possible, so it is necessary to avoid connecting extra devices to the high-voltage side circuit of the network transformer. There is.

【００１１】そこで、高圧配電線側で生じた地絡事故
を、ネットワーク変圧器の低圧側の回路で検出できるよ
うにするのが望ましいが、高圧配電線側で地絡事故が生
じた際に流れる零相電流は絶縁変圧器からなるネットワ
ーク変圧器を通らないため、従来の地絡検出装置をネッ
トワーク変圧器の低圧側の回路に接続しても高圧配電線
側の地絡事故を検出することはできない。Therefore, it is desirable that the ground fault occurring on the high voltage distribution line side be detected by the circuit on the low voltage side of the network transformer. Since the zero-phase current does not pass through the network transformer consisting of an insulating transformer, it is not possible to detect a ground fault on the high-voltage distribution line side even if a conventional ground fault detection device is connected to the low-voltage side circuit of the network transformer. Can not.

【００１２】高圧配電線に高圧側が接続された受電用変
圧器を備えたネットワーク受配電設備以外の受配電設
備、例えば、低圧側に分散型電源を連系している受配電
設備でも、同様の理由により、従来の地絡検出装置を用
いて受電用変圧器の低圧側の回路で高圧配電線側の回路
の地絡事故を検出することはできない。The same applies to a power receiving and distribution facility other than a network power receiving and distribution facility having a power receiving transformer in which a high voltage side is connected to a high voltage distribution line, for example, a power receiving and distribution facility in which a distributed power supply is connected to a low voltage side. For this reason, it is not possible to detect a ground fault in the circuit on the high voltage distribution line side with the circuit on the low voltage side of the power receiving transformer using the conventional ground fault detecting device.

【００１３】本発明の目的は、配電系統に設けられてい
る受電用変圧器の低圧側の回路で高圧配電線側の地絡事
故を検出することができるようにした配電系統の地絡検
出装置を提供することにある。An object of the present invention is to provide a ground fault detecting device for a distribution system in which a low voltage side circuit of a power receiving transformer provided in a power distribution system can detect a ground fault on a high voltage distribution line. Is to provide.

【００１４】本発明の他の目的は、高圧配電線の地絡事
故が生じたときにその事故を受電用変圧器の低圧側の回
路で検出することにより受電用変圧器の高圧側の回路と
低圧側の回路とを切り離して、事故が生じた高圧配電線
への給電を停止するようにした受配電設備を提供するこ
とにある。Another object of the present invention is to detect the occurrence of a ground fault in a high-voltage distribution line by using the low-voltage side circuit of the power receiving transformer, thereby detecting the ground fault in the high-voltage distribution line. An object of the present invention is to provide a power receiving / distributing facility which disconnects a circuit on a low voltage side and stops power supply to a high voltage distribution line in which an accident has occurred.

【００１５】[0015]

【課題を解決するための手段】本発明は、電源変電所か
ら引き出された複数の高圧配電線にそれぞれ絶縁変圧器
からなる受電用変圧器を備えた受配電設備が接続されて
いる配電系統の高圧配電線で地絡事故が生じたことを検
出する地絡検出装置に係わるもので、受電用変圧器の低
圧側の回路を流れる３相交流電流を検出する３相交流検
出部と、３相交流検出部により検出された３相交流電流
の基本波の逆相分を検出する基本波逆相分検出部と、該
基本波逆相分検出部により検出された逆相分から地絡事
故の発生の有無を判定する地絡判定部とを備えたことを
特徴とする。SUMMARY OF THE INVENTION The present invention relates to a power distribution system in which a plurality of high-voltage distribution lines drawn from a power substation are connected to a power receiving and distribution facility having a power receiving transformer comprising an insulating transformer. The present invention relates to a ground fault detection device for detecting that a ground fault has occurred in a high-voltage distribution line, and a three-phase AC detection unit for detecting a three-phase AC current flowing in a low-voltage side circuit of a power receiving transformer. A fundamental-wave negative-phase-sequence detector for detecting the negative-phase component of the fundamental wave of the three-phase AC current detected by the AC detector, and an occurrence of a ground fault from the negative-phase component detected by the fundamental-wave negative-phase component detector And a ground fault judging unit for judging the presence or absence of the ground fault.

【００１６】電源変電所から複数の高圧配電線が引き出
されている配電系統において、いずれかの高圧配電線で
地絡事故が生じると、変電所の遮断器が動作して事故が
生じた高圧配電線を変電所の変圧器から切り離す。この
とき、例えば他の健全な高圧配電線側から事故が生じた
高圧配電線につながる受電用変圧器の低圧側に給電され
るようになっていると、該受電用変圧器の低圧コイルに
励磁電流が流れるとともに、該受電用変圧器を通して地
絡事故が生じた高圧配電線側に、該高圧配電線の対地静
電容量を充電する充電電流が流れる。地絡が生じた高圧
配電線に流れる充電電流は不平衡３相交流電流となり、
該不平衡３相電流に含まれる成分のうち、正相分と逆相
分は受電用変圧器を低圧側から高圧側に通過するため、
事故が生じた高圧配電線につながる受電用変圧器の低圧
側の回路で逆相分電流の顕著な変化が生じる。In a distribution system in which a plurality of high-voltage distribution lines are drawn from a power substation, if a ground fault occurs in any one of the high-voltage distribution lines, a circuit breaker of the substation operates to cause the high-voltage distribution line in which the accident occurred. Disconnect the wires from the transformer at the substation. At this time, for example, if power is supplied from another healthy high-voltage distribution line to the low-voltage side of the power reception transformer connected to the high-voltage distribution line in which the accident has occurred, the low-voltage coil of the power reception transformer is excited. As the current flows, a charging current for charging the earth capacitance of the high-voltage distribution line flows to the high-voltage distribution line side where the ground fault has occurred through the power receiving transformer. The charging current flowing in the high-voltage distribution line where the ground fault has occurred becomes an unbalanced three-phase AC current,
Of the components included in the unbalanced three-phase current, the positive phase component and the negative phase component pass through the power receiving transformer from the low voltage side to the high voltage side,
A remarkable change in the negative phase component current occurs in the circuit on the low voltage side of the power receiving transformer connected to the high-voltage distribution line in which the accident occurred.

【００１７】従って、上記のように、受配電設備に設け
られた絶縁変圧器の低圧側の回路を流れる３相交流電流
から基本波の逆相分を検出するようにすると、検出され
た逆相分電流を予め定めた判定基準と比較することによ
り、受配電設備の各変圧器がつながる高圧配電線で地絡
事故が生じたか否かを検出することができる。Accordingly, as described above, when the reverse phase component of the fundamental wave is detected from the three-phase alternating current flowing through the low-voltage side circuit of the insulating transformer provided in the power receiving and distributing facility, the detected reverse phase is detected. By comparing the divided current with a predetermined criterion, it is possible to detect whether a ground fault has occurred in the high-voltage distribution line to which each transformer of the power receiving and distribution equipment is connected.

【００１８】上記逆相分から地絡事故の有無を判定する
には、例えば、一定の時間毎に逆相分を検出するように
しておいて、各検出時刻において検出された逆相分と前
回検出された逆相分との差をとることにより逆相分の変
化量を検出し、検出された逆相分の変化量が所定の判定
基準値以上になったときに地絡事故が発生したと判定す
るようにすればよい。In order to determine the presence or absence of a ground fault accident from the above-mentioned reverse phase, for example, the reverse phase is detected at predetermined time intervals, and the reverse phase detected at each detection time and the previous detection are detected. The amount of change in the reversed phase is detected by taking the difference from the detected reversed phase, and when the detected amount of change in the reversed phase is equal to or greater than a predetermined determination reference value, a ground fault has occurred. The determination may be made.

【００１９】また随時検出される逆相分に対して所定の
判定基準を定めておいて、随時検出される逆相分が判定
基準以上になったときに地絡事故が発生したと判定する
ようにしてもよい。Also, a predetermined criterion is determined for the negative phase component detected as needed, and when the negative phase component detected at any time exceeds the criterion, it is determined that a ground fault has occurred. It may be.

【００２０】上記のように、本発明によれば、配電系統
に設けられている各受電用変圧器の低圧側の回路でその
回路がつながる高圧配電線で地絡事故が発生したことを
検出することができるため、受電用変圧器と高圧配電線
との間の回路の構成を簡素にするという要請に応えつ
つ、各受配電設備で高圧配電線の地絡事故を検出して、
事故が生じた高圧配電線につながる回線を該高圧配電線
から切り離すなどの措置を講じることができる。As described above, according to the present invention, the low-voltage side circuit of each power receiving transformer provided in the distribution system detects that a ground fault has occurred in the high-voltage distribution line to which the circuit is connected. In response to the request to simplify the circuit configuration between the receiving transformer and the high-voltage distribution line, each power receiving and distribution facility detects a ground fault in the high-voltage distribution line,
It is possible to take measures such as disconnecting a line connected to the high-voltage distribution line in which the accident has occurred from the high-voltage distribution line.

【００２１】上記基本波逆相分検出部は、例えば、３相
交流検出部により検出された３相交流電流を３軸静止座
標系におけるベクトル量として扱って該３軸静止座標系
の３相交流電流を２軸が互いに直交する２軸静止座標系
における２相交流電流に変換する３相／２相変換部と、
２軸静止座標系を２相交流電流の基本波正相分の相回転
方向または基本波逆相分の相回転方向に回転する第１の
２軸回転座標系に変換することにより２相交流電流の基
本波正相分及び基本波逆相分の一方を直流電流に変換
し、他方を基本波周波数の２倍の周波数の交流電流に変
換する第１の回転座標変換部と、第１の回転座標変換部
の出力から２相交流電流の基本波正相分を除去して基本
波逆相分を抽出するフィルタ手段と、第１の２軸回転座
標系を該第１の２軸回転座標系と逆方向に回転する第２
の２軸回転座標系に変換することにより、フィルタ手段
により抽出された２相交流電流の基本波逆相分を２軸静
止座標系における２相交流電流の基本波逆相分に逆変換
する第２の回転座標変換部とを備えることにより構成で
きる。この場合、第２の回転座標変換部から得られる２
相交流電流の基本波逆相分を基本波逆相分検出部の検出
出力として用いるようにしてもよく、該２相交流電流の
基本波逆相分を２相／３相変換することにより得た３相
交流電流の基本波逆相分を基本波逆相分検出部の検出出
力として用いるようにしてもよい。The fundamental wave antiphase detecting section treats the three-phase alternating current detected by the three-phase alternating current detecting section as a vector quantity in the three-axis stationary coordinate system, and treats the three-phase alternating current in the three-axis stationary coordinate system. A three-phase / two-phase converter for converting a current into a two-phase alternating current in a two-axis stationary coordinate system in which two axes are orthogonal to each other;
The two-phase AC current is converted by converting the two-axis stationary coordinate system into a first two-axis rotating coordinate system that rotates in the phase rotation direction of the fundamental wave positive phase or the fundamental wave reverse phase of the two-phase AC current. A first rotation coordinate conversion unit for converting one of the fundamental wave positive phase component and the fundamental wave negative phase component into a DC current, and converting the other into an AC current having a frequency twice as high as the fundamental wave frequency; Filter means for removing the positive-phase component of the fundamental wave of the two-phase alternating current from the output of the coordinate conversion unit and extracting the negative-phase component of the fundamental wave, and converting the first two-axis rotating coordinate system into the first two-axis rotating coordinate system Second rotating in the opposite direction to
The two-axis rotating coordinate system is converted into a two-axis rotating coordinate system, whereby the two-phase alternating current extracted by the filter means in the two-phase alternating current is inversely transformed into the two-phase alternating current in the two-axis stationary coordinate system. And two rotational coordinate conversion units. In this case, 2 obtained from the second rotation coordinate conversion unit
The opposite phase component of the fundamental wave of the phase alternating current may be used as a detection output of the fundamental phase opposite phase detection unit, and is obtained by converting the fundamental phase opposite phase component of the two-phase alternating current into two-phase / three-phase conversion. The reversed-phase component of the fundamental wave of the three-phase alternating current may be used as the detection output of the fundamental-wave reversed-phase component detection unit.

【００２２】上記３相／２相変換部と、第１の回転座標
変換部と、フィルタ手段と、第２の回転座標変換部と、
地絡判定部とは、コンピュータと、該コンピュータに実
行させる所定のプログラムとにより実現することができ
る。The three-phase / two-phase converter, the first rotational coordinate converter, the filter means, the second rotational coordinate converter,
The ground fault determining unit can be realized by a computer and a predetermined program executed by the computer.

【００２３】本発明において、３相不平衡電流の逆相分
を検出するための演算は、３相の各相の電流にベクトル
演算子ａ［＝exp{ｊ（２π／３)}］及びａ² を乗じるこ
とにより逆相分を求める対称座標法によってもよい。In the present invention, the operation for detecting the reverse phase component of the three-phase unbalanced current is performed by using vector operators a [= exp {j (2π / 3)}] and a A symmetrical coordinate method for obtaining the inverse phase component by multiplying by ² may be used.

【００２４】但し、対称座標法により３相不平衡電流の
逆相分を求めるためには、ベクトル演算子ａ，ａ² を乗
じるための移相演算と、各相電流の平均化処理とを必要
とするため、演算に要する時間が長くなり、逆相分を検
出するまでに時間がかかるのを避けられない。However, in order to obtain the negative phase component of the three-phase unbalanced current by the symmetric coordinate method, a phase shift operation for multiplying the vector operators a and a ² and an averaging process for each phase current are required. , The time required for the operation is prolonged, and it is inevitable that it takes a long time to detect the reverse phase component.

【００２５】これに対し、上記のように、座標変換法に
より逆相分を求めるようにすれば、演算を比較的短い時
間で終えることができるため、逆相分の検出を高速で行
なうことができ、逆相分電流の時々刻々の変化を容易か
つ迅速に検出することができる。On the other hand, if the reverse phase component is obtained by the coordinate transformation method as described above, the calculation can be completed in a relatively short time, so that the reverse phase component can be detected at a high speed. This makes it possible to easily and quickly detect the moment-to-moment change of the negative phase current.

【００２６】本発明において、第２の回転座標変換部か
ら得られる２相交流電流の基本波逆相分を基本波逆相分
検出部の検出出力として用いるようにした場合には、３
相不平衡電流の様相を検証することはできない。しか
し、高圧配電線側の回路で地絡事故が生じたことの検出
のみを行なうのであれば、第２の回転座標変換部から得
られる２相交流電流の基本波逆相分を基本波逆相分検出
部の検出出力として用いてもなんら問題はない。In the present invention, when the fundamental phase reversed-phase component of the two-phase alternating current obtained from the second rotating coordinate transformation unit is used as a detection output of the fundamental wave reversed-phase component detecting unit, 3
The aspect of the phase unbalanced current cannot be verified. However, if only the detection of the occurrence of the ground fault in the circuit on the high-voltage distribution line side is performed, the fundamental wave reverse phase component of the two-phase AC current obtained from the second rotating coordinate conversion unit is converted to the fundamental wave reverse phase. There is no problem even if it is used as a detection output of the minute detection unit.

【００２７】第２の回転座標変換部から得られる２相交
流電流の基本波逆相分を２相／３相変換することにより
得た基本波３相交流の逆相分を基本波逆相分検出部の検
出出力として用いるようにした場合には、高圧配電線側
の回路で地絡事故が生じた場合に、その地絡事故を検出
することができるだけでなく、受電用変圧器を流れる３
相不平衡電流の様相の検証をも行なうことができる。The negative phase component of the three-phase alternating current of the fundamental wave obtained by performing two-phase / three-phase conversion of the negative phase component of the two-phase alternating current obtained from the second rotating coordinate converter is converted into the negative phase component of the fundamental wave. When used as a detection output of the detection unit, when a ground fault occurs in the circuit on the high voltage distribution line side, not only can the ground fault be detected, but also the ground fault can be detected.
Verification of the aspect of the phase imbalance current can also be performed.

【００２８】上記３相交流検出部は、例えば受電用変圧
器の低圧側回路に取り付けた変流器により構成できる
が、通常、ネットワーク受配電設備などの受配電設備で
は、受電用変圧器の低圧側の回路に変流器が設けられて
いるので、その既設の変流器を利用して上記３相交流検
出部を構成することができる。The above-mentioned three-phase AC detector can be constituted by a current transformer attached to a low-voltage side circuit of a power receiving transformer, for example. Since the current transformer is provided in the circuit on the side, the three-phase AC detector can be configured by using the existing current transformer.

【００２９】本発明に係わる受配電設備は、電源変電所
から引き出された高圧配電線に高圧側が接続された絶縁
変圧器からなる受電用変圧器と該受電用変圧器の高圧側
の回路または低圧側の回路を開閉する遮断器とを備えた
もので、受電用変圧器の低圧側の回路に設けられて該受
電用変圧器を通して流れる３相交流電流を検出する変流
器と、変流器により検出された３相交流電流の基本波の
逆相分を検出する基本波逆相分検出部と、基本波逆相分
検出部により検出された逆相分から受電用変圧器につな
がる高圧配電線側の回路で地絡事故が発生したか否かを
判定する地絡判定部と、該地絡判定部により地絡事故が
発生したと判定した時に遮断器に遮断指令を与える遮断
器制御部とを備えたことを特徴とする。The power receiving and distribution equipment according to the present invention comprises a power receiving transformer comprising an insulating transformer having a high voltage side connected to a high voltage distribution line drawn from a power substation, and a high voltage side circuit or a low voltage side of the power receiving transformer. A current transformer provided with a circuit breaker that opens and closes a circuit on the power receiving side, the current transformer being provided in a low voltage side circuit of the power receiving transformer and detecting a three-phase AC current flowing through the power receiving transformer; And a high-voltage distribution line connected to the power receiving transformer from the negative-phase component detected by the basic-wave negative-phase component detection unit. A ground fault determining unit that determines whether a ground fault has occurred in the circuit on the side, and a circuit breaker control unit that gives a break command to the circuit breaker when the ground fault determining unit determines that a ground fault has occurred. It is characterized by having.

【００３０】上記受配電設備としては、電源変電所から
引き出された複数の高圧配電線にそれぞれ高圧側が接続
された絶縁変圧器からなる複数のネットワーク変圧器
と、該複数のネットワーク変圧器に対して共通に設けら
れたネットワーク母線と、各ネットワーク変圧器の低圧
側とネットワーク母線との間に設けられたネットワーク
プロテクタとを備えたネットワーク受配電設備が多く用
いられている。ネットワークプロテクタは、対応するネ
ットワーク変圧器の低圧側とネットワーク母線との間に
設けられたプロテクタ遮断器と、対応するネットワーク
変圧器の低圧側の回路を流れる電流を検出する変流器
と、対応するネットワーク変圧器の低圧側から高圧側に
逆電力の潮流が生じたことを検出したときにプロテクタ
遮断器に遮断指令を与えるネットワーク継電器とを備え
ていて、ネットワーク継電器が逆電力の潮流を検出した
ときにプロテクタ遮断器を遮断する。The power receiving and distribution equipment includes a plurality of network transformers each including an insulating transformer having a high voltage side connected to a plurality of high voltage distribution lines drawn from a power substation, and a plurality of network transformers. 2. Description of the Related Art A network power receiving / distributing facility including a network bus provided in common and a network protector provided between a low voltage side of each network transformer and the network bus is often used. The network protector includes a protector breaker provided between the low voltage side of the corresponding network transformer and the network bus, and a current transformer that detects a current flowing through a circuit on the low voltage side of the corresponding network transformer. A network relay that gives a break command to the protector breaker when detecting that a reverse power flow has occurred from the low voltage side to the high voltage side of the network transformer, and when the network relay detects the reverse power flow Shut off the protector circuit breaker.

【００３１】このようなネットワーク受配電設備に本発
明を適用する場合には、上記変流器が検出した３相交流
電流の基本波の逆相分を検出する基本波逆相分検出部
と、該基本波逆相分検出部が検出した逆相分から対応す
るネットワーク変圧器につながる回路で地絡事故が発生
したか否かを判定する地絡判定部と、地絡判定部が地絡
事故が発生したと判定したときにプロテクタ遮断器に遮
断指令を与える遮断器制御部とをネットワークプロテク
タに設ける。When the present invention is applied to such a network power receiving and distributing facility, a fundamental wave reverse phase component detecting unit for detecting a reverse phase component of a fundamental wave of the three-phase alternating current detected by the current transformer, A ground fault determining unit that determines whether a ground fault has occurred in a circuit connected to a corresponding network transformer from the negative phase component detected by the fundamental wave negative phase component detecting unit. A circuit breaker control unit for giving a break command to the protector circuit breaker when it is determined that the breaker has occurred is provided in the network protector.

【００３２】上記のようにネットワーク受配電設備に地
絡検出装置を設けておくと、受配電設備内で高圧配電線
側の回路の地絡事故を検出することができるため、地絡
事故が検出された高圧配電線につながる受電用変圧器の
高圧側の回路と低圧側の回路とを切り離して、事故が生
じた高圧配電線への給電を停止するなどの措置を迅速に
講じることができるようになる。If a ground fault detecting device is provided in the network power receiving and distribution equipment as described above, a ground fault in the circuit on the high-voltage distribution line side can be detected in the power receiving and distribution equipment. The high-voltage circuit and the low-voltage circuit of the receiving transformer connected to the high-voltage distribution line that was disconnected, so that measures such as stopping power supply to the high-voltage distribution line in which the accident occurred can be taken promptly. become.

【００３３】[0033]

【発明の実施の形態】以下図面を参照して本発明に係わ
る地絡検出装置の構成例を説明する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A configuration example of a ground fault detecting device according to the present invention will be described below with reference to the drawings.

【００３４】図４は本発明を適用する配電系統の構成例
を示したもので、同図において１は発電所２に送電線を
通して高圧側が接続された変圧器１A1〜１A3と、変圧器
１A1〜１A3のそれぞれの低圧側に接続された母線１B1〜
１B3とを備えた電源側変電所である。FIG. 4 shows an example of the configuration of a distribution system to which the present invention is applied. In FIG. 4, reference numeral 1 denotes transformers 1A1 to 1A3 connected to a power plant 2 through a transmission line on the high voltage side, and transformers 1A1 to 1A1. Buses 1B1 to 1A3 connected to each low-voltage side
1B3.

【００３５】変電所１の母線１B1〜１B3にはそれぞれ遮
断器１C1〜１C3を介して高圧配電線３ａ〜３ｃが接続さ
れている。母線１B3には更に遮断器１C4を通して高圧配
電線３ｄが接続されている。この例では、変圧器１A1〜
１A3から母線１B1〜１B3と遮断器１C1〜１C4とを通して
配電線３ａ〜３ｄに２０ＫＶ級の特別高圧の電圧が印加
されている。The high voltage distribution lines 3a to 3c are connected to the buses 1B1 to 1B3 of the substation 1 via circuit breakers 1C1 to 1C3, respectively. The bus 1B3 is further connected to a high voltage distribution line 3d through a circuit breaker 1C4. In this example, the transformers 1A1 ~
An extra high voltage of 20 KV class is applied from 1A3 to distribution lines 3a to 3d through buses 1B1 to 1B3 and circuit breakers 1C1 to 1C4.

【００３６】図示してないが、電源変電所１には配電線
３ａ〜３ｄを流れる電流が制限値を超えた時に遮断器１
C1〜１c4をトリップする過電流継電器（ＯＣ）と、高圧
配電線３ａ〜３ｃで地絡事故が発生した時に遮断器１c1
〜１C3をトリップする地絡継電器（ＧＲ）とが設けられ
ている。Although not shown, the circuit breaker 1 is connected to the power substation 1 when the current flowing through the distribution lines 3a to 3d exceeds a limit value.
An overcurrent relay (OC) tripping C1 to 1c4 and a circuit breaker 1c1 when a ground fault occurs in the high voltage distribution lines 3a to 3c.
And a ground fault relay (GR) that trips .about.1C3.

【００３７】図示の例では、本発明に係わるネットワー
ク受配電設備４が高圧配電線３ａ〜３ｃに接続されてい
る。この受配電設備は、高圧配電線３ａ〜３ｃにそれぞ
れ断路器４Aa〜４Acを通して高圧側が接続されたネット
ワーク変圧器４Ba〜４Bcと、変圧器４Ba〜４Bcの低圧側
にそれぞれプロテクタヒューズ４Ca〜４Ccを通して一端
が接続されたプロテクタ遮断器４Da〜４Dcと、遮断器４
Da〜４Dcの他端に接続されたネットワーク母線ＢＵＳ1
と、遮断器４Da〜４Dcを制御する遮断器制御部４Ea〜４
Ecとを備えている。変圧器４Ba〜４Bcの低圧側の回路に
は変流器４Fa〜４Fcが取り付けられていて、これらの変
流器により検出された３相交流の信号が遮断器制御部４
Ea〜４Ecに与えられている。遮断器制御部４Ea〜４Ecに
はまたネットワーク変圧器４Ba〜４Bcの低圧側の電圧が
与えられている。In the illustrated example, the network power receiving and distribution equipment 4 according to the present invention is connected to the high voltage distribution lines 3a to 3c. The power receiving and distribution equipment includes network transformers 4Ba to 4Bc having high voltage sides connected to high voltage distribution lines 3a to 3c through disconnectors 4Aa to 4Ac, respectively, and one end through protector fuses 4Ca to 4Cc at low voltage sides of the transformers 4Ba to 4Bc. Is connected to the protector circuit breaker 4Da-4Dc and the circuit breaker 4
Network bus BUS1 connected to the other end of Da ~ 4Dc
And circuit breaker control units 4Ea to 4E controlling circuit breakers 4Da to 4Dc
Ec. Current transformers 4Fa to 4Fc are attached to the low voltage side circuits of the transformers 4Ba to 4Bc, and the three-phase AC signals detected by these current transformers are transmitted to the circuit breaker control unit 4.
Ea to 4Ec. The circuit breaker controllers 4Ea to 4Ec are also supplied with voltages on the low voltage side of the network transformers 4Ba to 4Bc.

【００３８】遮断器制御部４Ea〜４Ecはそれぞれ、ネッ
トワーク継電器を備えていて、ネットワーク変圧器４Ba
〜４Bcの低圧側から高圧側に（ネットワーク母線側ＢＵ
Ｓ1から高圧配電線３ａ〜３ｃ側に）しきい値以上の逆
電力の潮流が生じた時に、プロテクタ遮断器４Da〜４Dc
をトリップするようになっている。Each of the circuit breaker control units 4Ea to 4Ec includes a network relay, and includes a network transformer 4Ba.
From the low-pressure side to the high-pressure side (network bus side BU)
When a reverse power flow equal to or higher than the threshold value occurs on the high voltage distribution lines 3a to 3c side from S1, the protector breakers 4Da to 4Dc
Is to trip.

【００３９】ネットワーク母線ＢＵＳ1 には、高圧配電
線３ａ〜３ｃの特別高圧の電圧（２２ＫＶ）をネットワ
ーク変圧器４Ba〜４Bcにより降圧して得た電圧（例えば
４００Ｖ）が印加されている。To the network bus BUS1, a voltage (for example, 400 V) obtained by lowering the extra high voltage (22 KV) of the high voltage distribution lines 3a to 3c by the network transformers 4Ba to 4Bc is applied.

【００４０】図示の例では、プロテクタヒューズ４Ca、
プロテクタ遮断器４Da、変流器４Fa及び遮断器制御部４
Eaにより、ネットワークプロテクタ４Gaが構成され、プ
ロテクタヒューズ４Cb、プロテクタ遮断器４Db、変流器
４Fb及び遮断器制御部４Ebにより、ネットワークプロテ
クタ４Gbが構成されている。またプロテクタ遮断器４D
c、変流器４Fc及び遮断器制御部４Ecにより、ネットワ
ークプロテクタ４Gcが構成されている。In the example shown, the protector fuse 4Ca,
Protector circuit breaker 4Da, current transformer 4Fa and circuit breaker controller 4
A network protector 4Ga is configured by Ea, and a network protector 4Gb is configured by the protector fuse 4Cb, the protector circuit breaker 4Db, the current transformer 4Fb, and the circuit breaker control unit 4Eb. In addition, protector breaker 4D
c, the current transformer 4Fc and the circuit breaker controller 4Ec constitute a network protector 4Gc.

【００４１】また、図示の例では、本発明に係わるネッ
トワーク受配電設備以外に、本発明に係わる地絡検出装
置を用いた受配電設備として、低圧側に分散型電源を連
系した常用予備受配電設備５が高圧配電線３ａ及び３ｂ
に接続されている。この受配電設備は、配電線３ａ及び
３ｂにそれぞれ遮断器５Aa及び５Abを介して高圧側が接
続された受電用変圧器５Ｂと、受電用変圧器５Ｂの低圧
側に遮断器５Ｃを通して接続された母線ＢＵＳ2 と、変
圧器５Ｂの低圧側の回路に取り付けられた変流器５Ｄ
と、変流器５Ｄの出力及び変圧器５Ｂの低圧側の電圧を
入力として、変圧器５Ｂの低圧側から高圧側に逆電力の
潮流が生じたことが検出されたときに遮断器５Ｃをトリ
ップする継電器を有する遮断器制御部５Ｅとを備えてい
る。母線ＢＵＳ2 には、特別高圧の電圧を変圧器５Ｂに
より降圧して得た電圧（例えば６０００Ｖ）が印加され
ている。In the illustrated example, in addition to the network power receiving and distribution equipment according to the present invention, as a power receiving and distribution equipment using the ground fault detecting device according to the present invention, a regular standby power receiving system in which a distributed power supply is connected to the low voltage side is used. Power distribution equipment 5 is high voltage distribution lines 3a and 3b
It is connected to the. The power receiving and distribution equipment includes a power receiving transformer 5B having a high voltage connected to distribution lines 3a and 3b via circuit breakers 5Aa and 5Ab, respectively, and a bus connected to a low voltage side of the power receiving transformer 5B through a circuit breaker 5C. BUS2 and a current transformer 5D attached to the circuit on the low voltage side of the transformer 5B
When the output of the current transformer 5D and the voltage on the low voltage side of the transformer 5B are input, and when it is detected that a reverse power flow has occurred from the low voltage side to the high voltage side of the transformer 5B, the circuit breaker 5C is tripped. And a breaker control unit 5E having a relay. A voltage (for example, 6000 V) obtained by stepping down an extra high voltage by the transformer 5B is applied to the bus BUS2.

【００４２】図示の例では、ネットワーク母線ＢＵＳ1
に開閉器ＳＷ0 を通して配電線用変圧器Ｔr の高圧側が
接続されるとともに、開閉器ＳＷ1 〜ＳＷ4 を通して負
荷Ａ1 〜Ａ4 が接続されている。また常用予備受配電設
備５の母線ＢＵＳ2 には負荷Ａ5 及びＡ6 が接続され、
高圧配電線３ｄには、２２［ＫＶ］の負荷Ａ7 が接続さ
れている。In the illustrated example, the network bus BUS1
Is connected to the high voltage side of the distribution line transformer Tr through a switch SW0, and connected to loads A1 to A4 through switches SW1 to SW4. Loads A5 and A6 are connected to the bus BUS2 of the regular standby power receiving and distribution equipment 5,
A load A7 of 22 [KV] is connected to the high voltage distribution line 3d.

【００４３】更に、ネットワーク母線ＢＵＳ1 及び常用
予備受配電設備の母線ＢＵＳ2 にそれぞれ分散型電源Ｇ
1 及びＧ2 が接続されている。Further, the distributed power sources G are respectively connected to the network bus BUS1 and the bus BUS2 of the regular standby power distribution equipment.
1 and G2 are connected.

【００４４】図４には図示してないが、配電系統には更
に配電塔などの各種の受配電設備や分散型電源が接続さ
れることがある。Although not shown in FIG. 4, the power distribution system may be further connected to various power receiving and distribution facilities such as a power distribution tower and a distributed power supply.

【００４５】図４に示したような配電系統において、例
えば高圧配電線３ａのＸ点で地絡事故が発生した場合に
は、変電所１に設けられている地絡保護継電器が変圧器
１A1と事故が生じた高圧配電線３ａとの間に設けられた
遮断器１c1に遮断動作を行なわせて、地絡事故が生じた
配電線３ａを変電所の変圧器１A1から切り離す。このと
き、健全な高圧配電線３ｂ及び３ｃ側から、ネットワー
ク受配電設備４内の回路（断路器４Ab−ネットワーク変
圧器４Bb−遮断器４Dbの回路及び断路器４Ac−ネットワ
ーク変圧器４Bc−遮断器４Dcの回路）とネットワーク母
線ＢＵＳ1 とを通して事故が起きた高圧配電線３ａにつ
ながるネットワーク変圧器４Baに電流が流れ込み、該変
圧器４Baの低圧側から高圧側に逆電力の潮流が生じる。
このとき、遮断器制御部４Ｅa に設けられたネットワー
ク継電器は、変圧器４Baの励磁電流と、ネットワーク母
線ＢＵＳ1 側から変圧器４Baを通して高圧配電線３ａの
対地静電容量Ｃに流れる充電電流との合成電流及び変圧
器４Ｂa の低圧側の電圧を検出して逆電力の潮流を検出
し、プロテクタ遮断器４Daを開く。In the distribution system as shown in FIG. 4, for example, when a ground fault occurs at the point X of the high voltage distribution line 3a, the ground fault protection relay provided in the substation 1 is connected to the transformer 1A1. The circuit breaker 1c1 provided between the high-voltage distribution line 3a where the accident has occurred and the high-voltage distribution line 3a performs a breaking operation to disconnect the distribution line 3a where the ground fault has occurred from the transformer 1A1 of the substation. At this time, from the sound high-voltage distribution lines 3b and 3c, the circuits in the network power receiving and distribution equipment 4 (disconnector 4Ab-network transformer 4Bb-circuit breaker 4Db and disconnector 4Ac-network transformer 4Bc-circuit breaker 4Dc Current flows into the network transformer 4Ba connected to the high-voltage distribution line 3a in which the accident has occurred via the network bus BUS1 and the network bus BUS1, and reverse power flows from the low voltage side to the high voltage side of the transformer 4Ba.
At this time, the network relay provided in the breaker control unit 4Ea combines the exciting current of the transformer 4Ba and the charging current flowing from the network bus BUS1 through the transformer 4Ba to the ground capacitance C of the high-voltage distribution line 3a. The current and the voltage on the low voltage side of the transformer 4Ba are detected to detect the reverse power flow, and the protector breaker 4Da is opened.

【００４６】図４に示したネットワーク受配電設備４に
おいて、逆電力に対するネットワーク継電器のしきい値
を低くしておくと、高圧配電線３ａ〜３ｃに地絡事故が
生じていない状態で、分散型電源Ｇ1 からネットワーク
母線ＢＵＳ1 とネットワーク変圧器４Ba〜４Bcとを通し
て配電線３ａ〜３ｃ側に逆電力の潮流が生じたときにも
プロテクタ遮断器４Da〜４Dcが遮断動作を行ってしま
う。In the network power receiving and distribution equipment 4 shown in FIG. 4, if the threshold value of the network relay for the reverse power is reduced, the distributed high-voltage power distribution lines 3a to 3c can be distributed without causing a ground fault. Even when a reverse power flow occurs from the power supply G1 to the distribution lines 3a to 3c through the network bus BUS1 and the network transformers 4Ba to 4Bc, the protector circuit breakers 4Da to 4Dc perform the breaking operation.

【００４７】上記のように定常時の逆電力の潮流に応答
してネットワーク受配電設備４内の遮断器が遮断動作を
行なうことは避ける必要がある。従って、図４に示した
ように系統に分散型電源が連系している場合には、受配
電設備４内で逆電力の潮流を検出している継電器のしき
い値を高く設定して、該受配電設備内の遮断器の動作に
抑制をかける必要があり、高圧配電線３ａ〜３ｃ側で地
絡事故が生じた時に、事故が生じた高圧配電線につなが
る回線を切り離すことができなくなることがある。この
ような事態が生じないようにするためには、ネットワー
ク受配電設備４内に高圧配電線の地絡事故を検出する地
絡検出装置を設けて、該地絡検出装置により高圧配電線
の地絡事故が検出された時にネットワーク変圧器の高圧
側の回路と低圧側の回路とを切り離すようにしておけば
よい。As described above, it is necessary to prevent the circuit breaker in the network power receiving / distributing facility 4 from performing the shut-down operation in response to the flow of the reverse power in the steady state. Therefore, as shown in FIG. 4, when the distributed power supply is connected to the grid, the threshold value of the relay that detects the reverse power flow in the power receiving and distribution equipment 4 is set high, It is necessary to suppress the operation of the circuit breaker in the power receiving and distribution equipment, and when a ground fault occurs on the high voltage distribution lines 3a to 3c, it becomes impossible to disconnect the line connected to the high voltage distribution line where the accident has occurred. Sometimes. In order to prevent such a situation from occurring, a ground fault detecting device for detecting a ground fault of the high voltage distribution line is provided in the network power receiving and distribution equipment 4, and the ground fault detecting device detects the ground fault of the high voltage distribution line. The circuit on the high-voltage side and the circuit on the low-voltage side of the network transformer may be disconnected when an accident is detected.

【００４８】図１は、本発明に係わる地絡検出装置の全
体的な構成を示したもので、同図において、１０ｕ〜１
０ｗは配電系統に接続されている絶縁変圧器（図４の例
では、ネットワーク変圧器４Ba〜４Bc）の低圧側のＵ，
Ｖ，Ｗ３相の回路であり、これらの回路には、変流器Ｃ
Ｔau，ＣＴav及びＣＴawが取り付けられている。ネット
ワーク受配電設備のように、絶縁変圧器の低圧側の回路
に既に変流器（例えば図４の変流器４Fa〜４Fc）が設け
られている場合には、その既設の変流器を変流器ＣＴau
〜ＣＴawとして利用することができる。図１に示した例
では、変流器ＣＴau，ＣＴav及びＣＴawにより、絶縁変
圧器の低圧側の回路を流れる３相交流電流を検出する３
相交流検出部１１が構成され、この３相交流検出部１１
から得られる３相交流電流の検出値が基本波逆相分検出
部１２に与えられている。FIG. 1 shows the overall configuration of a ground fault detecting device according to the present invention.
0w is U, U on the low-voltage side of the insulating transformer (the network transformers 4Ba to 4Bc in the example of FIG. 4) connected to the distribution system.
V and W three-phase circuits. These circuits include a current transformer C
Tau, CTav and CTaw are attached. When a current transformer (for example, the current transformers 4Fa to 4Fc in FIG. 4) is already provided in the circuit on the low voltage side of the insulating transformer as in the network power receiving and distribution equipment, the existing current transformer is transformed. Flower CTau
~ CTaw. In the example shown in FIG. 1, the three-phase AC current flowing through the low-voltage side circuit of the insulating transformer is detected by the current transformers CTau, CTav, and CTaw.
A three-phase alternating current detection unit 11 is configured.
The detected value of the three-phase alternating current obtained from the above is supplied to the fundamental-wave negative-phase-sequence detecting unit 12.

【００４９】基本波逆相分検出部１２は、座標変換法に
より不平衡３相交流電流の逆相分を検出する部分で、こ
の基本波逆相分検出部は、３相交流検出部１１により検
出された３相交流を３軸静止座標系におけるベクトル量
として扱って該３軸静止座標系における３相交流電流を
２軸が互いに直交する２軸静止座標系における２相交流
電流に変換する３相／２相変換部１３と、２軸静止座標
系を２相交流電流の基本波正相分の相回転方向または基
本波逆相分の相回転方向に回転する第１の２軸回転座標
系に変換することにより３相／２相変換部１３が求めた
２相交流電流の基本波正相分及び基本波逆相分の一方を
直流電流に変換し、他方を基本波周波数の２倍の周波数
の交流電流に変換する第１の回転座標変換部１４と、該
第１の回転座標変換部１４の出力から２相交流電流の基
本波正相分を除去して基本波逆相分を抽出するフィルタ
手段１５と、第１の２軸回転座標系を該第１の２軸回転
座標系と逆方向に回転する第２の２軸回転座標系に変換
することにより、フィルタ手段１５により抽出された２
相交流電流の基本波逆相分を２軸静止座標系における２
軸静止座標系における２相交流電流の基本波逆相分に逆
変換する第２の回転座標変換部１６と、該基本波２相交
流を２相／３相変換することにより３相交流電流の基本
波逆相分を得る２相／３相変換部１７とからなってい
る。２相／３相変換部１７から得られる３相交流電流の
基本波逆相分は、地絡事故の発生の有無を判定する地絡
判定部１８に与えられている。基本波逆相分検出部１２
及び地絡判定部１８は、マイクロコンピュータと該マイ
クロコンピュータに実行させる所定のプログラムとによ
り実現される。The fundamental wave reverse phase detecting section 12 detects the reverse phase of the unbalanced three-phase alternating current by the coordinate transformation method. Treating the detected three-phase alternating current as a vector quantity in a three-axis stationary coordinate system, and converting the three-phase alternating current in the three-axis stationary coordinate system into a two-phase alternating current in a two-axis stationary coordinate system in which two axes are orthogonal to each other. A phase / two-phase conversion unit 13 and a first two-axis rotating coordinate system that rotates the two-axis stationary coordinate system in a phase rotation direction corresponding to a fundamental positive phase or a negative phase reverse phase of a two-phase AC current. , The three-phase / two-phase converter 13 converts one of the fundamental-wave positive-phase component and the fundamental-wave negative-phase component of the two-phase AC current into a DC current, and the other of the two-phase AC current into twice the fundamental frequency. A first rotational coordinate converter 14 for converting the frequency into an alternating current; Filter means 15 for removing the positive-phase component of the fundamental wave of the two-phase alternating current from the output of the unit 14 and extracting the negative-phase component of the fundamental wave, and converting the first two-axis rotating coordinate system to the first two-axis rotating coordinate system Is converted into a second two-axis rotating coordinate system that rotates in the opposite direction to the two axes extracted by the filter means 15.
The opposite phase component of the fundamental wave of the phase alternating current is expressed as 2
A second rotating coordinate conversion unit 16 for inversely converting the two-phase alternating current into an inverse phase component of the two-phase alternating current in the axis stationary coordinate system, and a two-phase / 3-phase conversion of the two-phase alternating current to convert the three-phase alternating current into a three-phase alternating current; It comprises a two-phase / three-phase converter 17 for obtaining an inverse phase component of the fundamental wave. The negative-phase component of the three-phase alternating current obtained from the two-phase / three-phase converter 17 is supplied to a ground fault determining unit 18 that determines whether or not a ground fault has occurred. Fundamental wave reverse phase component detector 12
The ground fault determining unit 18 is realized by a microcomputer and a predetermined program executed by the microcomputer.

【００５０】３相／２相変換部１３は、３相交流検出部
１１により検出された３軸静止座標系の３相交流電流を
２軸が互いに直交する２軸静止座標系における２相交流
電流に変換する部分で、図２に示したように、Ｕ，Ｖ，
Ｗの３軸が平面上で互いに１２０度の角度間隔をもって
交差する３軸静止座標系をα及びβの２軸が直交する２
軸静止座標系に変換する演算（３相／２相変換）を行な
って、３軸静止座標系の３相交流Ｉｕ，Ｉｖ及びＩｗ
（文章中ではベクトル量を示すドットの表示を省略す
る。）の信号を、２軸静止座標系の２相交流電流Ｉα及
びＩβの信号に変換する。図２に示したように、３軸静
止座標と２軸静止座標とがなす角をδとした場合、３相
／２相変換の演算は下記の式［数１］の通りである。The three-phase / two-phase converter 13 converts the three-phase AC current of the three-axis stationary coordinate system detected by the three-phase AC detector 11 into the two-phase AC current of the two-axis stationary coordinate system in which two axes are orthogonal to each other. , And as shown in FIG. 2, U, V,
A three-axis stationary coordinate system in which three axes of W intersect with each other at an angle interval of 120 degrees on a plane is defined by two axes in which α and β are orthogonal.
An operation (3-phase / 2-phase conversion) for converting to a three-axis stationary coordinate system is performed, and three-phase alternating currents Iu, Iv, and Iw of the three-axis stationary coordinate system are performed.
(The display of the dot indicating the vector amount is omitted in the text.) The signal is converted into signals of two-phase alternating currents Iα and Iβ in a two-axis stationary coordinate system. As shown in FIG. 2, when an angle formed by the three-axis stationary coordinates and the two-axis stationary coordinates is δ, the calculation of the three-phase / two-phase conversion is represented by the following equation [Equation 1].

【００５１】[0051]

【数１】 ここでδ＝０となるように、α軸及びβ軸を定めると、
上記の式は次の式［数２］のようになる。(Equation 1) Here, when the α axis and the β axis are determined so that δ = 0,
The above equation becomes like the following equation [Equation 2].

【００５２】[0052]

【数２】 また［数２］の式の電流（Ｉｕ，Ｉｖ，Ｉｗ）は、対称
座標法により、対称分である零相分電流Ｉ0 、正相分電
流Ｉ1 及び逆相分電流Ｉ2 とベクトル演算子ａ及びａ²
とを用いて、下記の［数３］のように表される。(Equation 2) The currents (Iu, Iv, Iw) in the equation (2) are obtained by the symmetrical coordinate method using the symmetrical components of the zero-phase current I0, the positive-phase current I1, and the negative-phase current I2, and the vector operators a and a ²
And is represented by the following [Equation 3].

【００５３】[0053]

【数３】 ここで、零相分電流を無視すると、Ｉ0 ＝０となるた
め、［数３］の式は下記の［数４］のようになる。(Equation 3) Here, if the zero-phase current is ignored, then I0 = 0, so the equation of [Equation 3] is as shown in the following [Equation 4].

【００５４】[0054]

【数４】 ［数４］の式を［数２］の式に代入すると、Ｉα及びＩ
βを求める式は下記の［数５］のようになる。(Equation 4) By substituting the equation of [Equation 4] into the equation of [Equation 2], Iα and Iα
The equation for determining β is as shown in the following [Equation 5].

【００５５】[0055]

【数５】 ここで［数５］の行列式を展開してＩαを演算する式を
求めると、下記の［数６］のようになる。(Equation 5) Here, when the determinant of [Equation 5] is expanded to obtain an equation for calculating Iα, the following [Equation 6] is obtained.

【００５６】[0056]

【数６】 ベクトル演算子ａ及びａ² はそれぞれ下記の［数７］及
び［数８］の通りである。(Equation 6) The vector operators a and a ² are as shown in the following [Equation 7] and [Equation 8], respectively.

【００５７】[0057]

【数７】 (Equation 7)

【数８】 ［数７］及び［数８］の式を［数６］の式に代入する
と、電流Ｉαは下記の式［数９］で与えられる。(Equation 8) When the equations of [Equation 7] and [Equation 8] are substituted into the equation of [Equation 6], the current Iα is given by the following equation [Equation 9].

【００５８】[0058]

【数９】 図３に示すように、基準電圧Ｖ1 と正相分電流Ｉ1 とが
なす角度をΦとし、基準電圧Ｖ1 と逆相分電流Ｉ2 がな
す角度をθとすると、Ｉ1 （ベクトル）＝Ｉ1ε
^{ｊ（ωｔ＋Φ）}、Ｉ2 （ベクトル）＝Ｉ2 ε
^{ｊ（ωｔ＋θ）}と表示できるため、電流Ｉαは、下記の
［数１０］で与えられる。(Equation 9) As shown in FIG. 3, when an angle formed between the reference voltage V1 and the positive-sequence component current I1 is Φ and an angle formed between the reference voltage V1 and the negative-sequence component current I2 is θ, I1 (vector) = I1ε
^{j (ωt + Φ)} , I 2 (vector) = I 2 ε
^Since it can be expressed as ^{j (ωt + θ)} , the current Iα is given by the following [Equation 10].

【００５９】[0059]

【数１０】 同様にして、電流Ｉβは、下記の式［数１１］から求め
られる。(Equation 10) Similarly, current Iβ is obtained from the following equation [Equation 11].

【００６０】[0060]

【数１１】 上記の式［数１０］及び［数１１］の演算をコンピュー
タに行なわせることにより、３相／２相変換を行い、２
軸静止座標系における２相交流Ｉα及びＩβを求める。[Equation 11] By causing the computer to perform the operations of the above equations [Equation 10] and [Equation 11], three-phase / two-phase conversion is performed.
The two-phase alternating currents Iα and Iβ in the axis stationary coordinate system are obtained.

【００６１】次に第１の回転座標変換部１４は、α，β
の２軸静止座標系を２相交流電流の基本波正相分の相回
転方向または基本波逆相分の相回転方向に相回転の速度
と同速度で回転する第１の２軸回転座標系に変換するこ
とにより３相／２相変換部１３が求めた２相交流電流Ｉ
α及びＩβの基本波正相分及び基本波逆相分の一方を直
流成分に変換し、他方を基本波周波数の２倍の周波数成
分に変換する。ここで、第１の２軸回転座標系を基本波
正相分の相回転方向と同方向に該基本波正相分と同速度
で回転させると、基本波正相分は直流分として現れ、基
本波逆相分は基本波の周波数の２倍の周波数の成分とし
て現れる。また第１の２軸回転座標系を基本波逆相分の
相回転方向と同方向に該逆相分と同速度で回転させる
と、基本波正相分は基本波周波数の２倍の周波数の成分
として現れ、基本波逆相分は直流分として現れる。Next, the first rotational coordinate converter 14 calculates α, β
First two-axis rotating coordinate system that rotates the two-axis stationary coordinate system at the same speed as the phase rotation speed in the phase rotation direction of the fundamental wave positive phase or the fundamental wave reverse phase of the two-phase AC current. To the two-phase AC current I obtained by the three-phase / two-phase conversion unit 13.
One of the component of the normal phase of the fundamental wave and the component of the opposite phase of the fundamental wave of α and Iβ are converted into a DC component, and the other is converted into a frequency component twice the fundamental frequency. Here, when the first two-axis rotating coordinate system is rotated at the same speed as the fundamental wave positive phase in the same direction as the phase rotation direction of the fundamental wave positive phase, the fundamental wave positive phase appears as a DC component, The opposite phase component of the fundamental wave appears as a component having a frequency twice the frequency of the fundamental wave. When the first two-axis rotating coordinate system is rotated at the same speed as the reverse phase component in the same direction as the phase rotation direction of the fundamental phase reverse phase, the fundamental normal phase component has a frequency twice as high as the fundamental frequency. The component appears as a component, and the fundamental-phase component appears as a DC component.

【００６２】第１の２軸回転座標系の回転方向はいずれ
の方向としてもよいが、以下の説明では、第１の２軸回
転座標系の回転方向が、基本波逆相分の相回転方向と同
方向（配電系統の電圧ベクトルの回転方向と逆方向）で
あるとする。The rotation direction of the first two-axis rotating coordinate system may be any direction, but in the following description, the rotating direction of the first two-axis rotating coordinate system is the phase rotation direction of the fundamental wave opposite phase. (The direction opposite to the rotation direction of the voltage vector of the distribution system).

【００６３】すなわち、２相変換した２相電流Ｉα及び
Ｉβ（いずれもベクトル量）のα，β直交２軸静止座標
系を、配電系統の電圧ベクトルと逆方向に、該電圧ベク
トルと同速度で回転する直交２軸回転座標系の２相電流
Ｉｐ及びＩｑ（ベクトル量）に変換する。直交２軸静止
座標系から直交２軸回転座標系への変換式は下記の式
［数１２］の通りである。That is, the α, β orthogonal two-axis stationary coordinate system of the two-phase converted two-phase currents Iα and Iβ (both are vector quantities) is converted in the opposite direction to the voltage vector of the distribution system at the same speed as the voltage vector. It is converted into two-phase currents Ip and Iq (vector quantities) in a rotating orthogonal two-axis rotating coordinate system. The conversion equation from the orthogonal two-axis stationary coordinate system to the orthogonal two-axis rotating coordinate system is as shown in the following equation [Equation 12].

【００６４】[0064]

【数１２】 この行列式を開いて回転座標系の電流Ｉｐを求めると下
記の［数１３］のようになる。(Equation 12) When this determinant is opened and the current Ip in the rotating coordinate system is obtained, the following equation 13 is obtained.

【００６５】[0065]

【数１３】 同様にして、回転座標系の電流Ｉｑは、下記の［数１
４］から求められる。(Equation 13) Similarly, the current Iq of the rotating coordinate system is represented by the following [Equation 1].
4].

【００６６】[0066]

【数１４】 回転座標系の電流Ｉｐ及びＩｑの第１項は正相分電流Ｉ
1 であり、角速度２ωｔの交流成分となる。また第２項
は逆相分電流Ｉ2 であり、この逆相分電流Ｉ2は時間的
要素がないので直流成分となる。[Equation 14] The first term of the currents Ip and Iq in the rotating coordinate system is the positive phase current I
1, which is an AC component having an angular velocity of 2ωt. The second term is the negative-sequence component current I2, which has no temporal element and therefore becomes a DC component.

【００６７】図１のフィルタ手段１５は、ローパスフィ
ルタからなっていて、上記Ｉｐ及びＩｑから交流成分
（正相分電流）を除去することにより、ｐ，ｑ２軸回転
座標系における逆相分電流を抽出する。The filter means 15 shown in FIG. 1 comprises a low-pass filter, and removes an AC component (a positive-phase current) from the above-described Ip and Iq to reduce the negative-phase current in the p- and q-axis rotary coordinate systems. Extract.

【００６８】ｐ，ｑ２軸回転座標系における逆相分電流
のｐ軸成分Ｉp-DCは下記の式［数１５］のようになる。The p-axis component Ip-DC of the negative-sequence component current in the p- and q-axis rotary coordinate systems is represented by the following equation (15).

【００６９】[0069]

【数１５】 またｐ，ｑ２軸回転座標系における逆相分電流のｑ軸成
分Ｉq-DCは下記の式［数１６］のようになる。(Equation 15) In addition, the q-axis component Iq-DC of the negative phase component current in the p- and q-axis rotation coordinate systems is represented by the following equation [Equation 16].

【００７０】[0070]

【数１６】 第２の回転座標変換部１６は、第１の回転座標変換部１
４により行った演算処理と逆の手順でｐ，ｑ２軸回転座
標系（第１の２軸回転座標系）を該第１の２軸回転座標
系と逆方向に、該第１の２軸回転座標系と同速度で回転
する第２の２軸回転座標系に変換することによって、フ
ィルタ手段１５により抽出された２相逆相分電流（上記
［数１５］及び［数１６］の逆相成分Ｉp-DC及びＩq-DC
を有する２相交流）を、α，β２軸静止座標系における
２相交流電流の基本波逆相分に逆変換する。(Equation 16) The second rotation coordinate conversion unit 16 includes the first rotation coordinate conversion unit 1.
In the reverse procedure of the arithmetic processing performed in step 4, the p- and q-axis two-axis coordinate system (first two-axis coordinate system) is rotated in the opposite direction to the first two-axis coordinate system. By converting to a second biaxial rotating coordinate system rotating at the same speed as the coordinate system, the two-phase negative-sequence current extracted by the filter means 15 (the negative-phase component of the above [Equation 15] and [Equation 16]) Ip-DC and Iq-DC
) Is inversely transformed into a two-phase alternating current in the α, β two-axis stationary coordinate system into a component of a fundamental wave opposite phase.

【００７１】２相／３相変換部１７は、第２の回転座標
変換部１６から得られる２相交流電流の基本波逆相分
を、３相／２相変換部１３で行った処理と逆の手順で３
軸静止座標系における３相交流電流の基本波逆相分（受
電用変圧器の低圧側の回路から検出された３相交流電流
Ｉｕ，Ｉｖ，Ｉｗに含まれる逆相分電流）に変換する。
地絡判定部１８は、基本波逆相分検出部１２により検出
された逆相分から地絡事故の発生の有無を判定する。基
本波逆相分検出部１２により検出された逆相分から地絡
事故の有無を判定するには、例えば、一定の時間毎に逆
相分を検出するようにしておいて、各検出時刻において
検出された逆相分と前回検出された逆相分との差をとる
ことにより逆相分の変化量を検出し、検出された逆相分
の変化量が所定の判定値以上になったときに地絡事故が
発生したと判定するようにすればよい。The two-phase / three-phase conversion unit 17 converts the two-phase alternating current obtained from the second rotation coordinate conversion unit 16 into the fundamental phase opposite phase to the processing performed by the three-phase / two-phase conversion unit 13. 3 in the procedure
The three-phase AC current is converted into a fundamental phase negative phase component (a negative phase component current included in the three-phase AC currents Iu, Iv, Iw detected from the low-voltage side circuit of the power receiving transformer) in the axis stationary coordinate system.
The ground fault determining unit 18 determines whether a ground fault has occurred based on the negative phase component detected by the fundamental wave negative phase detecting unit 12. In order to determine the presence / absence of a ground fault accident from the negative phase component detected by the fundamental phase negative phase detecting unit 12, for example, the negative phase component is detected at predetermined time intervals, and the detection is performed at each detection time. The amount of change in the reversed phase is detected by taking the difference between the detected reversed phase and the previously detected reversed phase, and when the detected amount of change in the reversed phase is greater than or equal to a predetermined determination value. It may be determined that a ground fault has occurred.

【００７２】また随時検出される逆相分に対して所定の
判定基準を定めておいて、検出された逆相分が判定基準
以上になったときに地絡事故が発生したと判定するよう
にしてもよい。Further, a predetermined criterion is determined for the negative phase component which is detected as needed, and when the detected negative phase component exceeds the criterion, it is determined that a ground fault has occurred. You may.

【００７３】上記の例では、第１の回転座標変換部１４
で、２軸回転座標系を系統電圧に含まれる逆相分の相回
転方向と同方向に回転させたが、該２軸回転座標系を系
統電圧に含まれる正相分の相回転方向と同方向に回転さ
せるようにしてもよい。この場合には、逆相分電流が基
本波周波数の２倍の周波数の信号として得られるので、
フィルタ手段１５はハイパスフィルタにより構成する。In the above example, the first rotational coordinate conversion unit 14
Then, the two-axis rotating coordinate system is rotated in the same direction as the phase rotation direction of the negative phase included in the system voltage, but the two-axis rotating coordinate system is rotated in the same direction as the phase rotation direction of the positive phase included in the system voltage. You may make it rotate in a direction. In this case, since the negative phase current is obtained as a signal having a frequency twice the fundamental frequency,
The filter means 15 is constituted by a high-pass filter.

【００７４】上記の例では、基本波逆相分検出部１２に
おいて、第２の回転座標変換部１６により得た２相交流
電流の逆相分を２相／３相変換部により３相交流電流の
逆相分に変換するようにしたが、このように構成する
と、外部回路で地絡事故が生じた場合に、その地絡事故
を検出することができるだけでなく、受電用変圧器を流
れる３相不平衡電流の様相の検証をも行なうことができ
る。In the above example, in the fundamental wave reverse phase component detecting section 12, the reverse phase component of the two-phase AC current obtained by the second rotational coordinate conversion section 16 is converted into the three-phase AC current by the two-phase / 3-phase conversion section. With this configuration, when a ground fault occurs in an external circuit, not only can the ground fault be detected, but also the current flowing through the power receiving transformer can be detected. Verification of the aspect of the phase imbalance current can also be performed.

【００７５】なお外部回路で地絡事故が生じたことの検
出のみを行なうのであれば、第２の回転座標変換部１６
から得られる２相交流電流の基本波逆相分を基本波逆相
分検出部の検出出力として用いてもなんら問題はないの
で、２相／３相変換部１７は省略することもできる。If the external circuit only detects that a ground fault has occurred, the second rotating coordinate conversion unit 16
There is no problem even if the fundamental wave reverse phase component of the two-phase alternating current obtained from the above is used as the detection output of the fundamental wave reverse phase component detection unit, so the two-phase / 3-phase conversion unit 17 can be omitted.

【００７６】図１に示した例では、３相交流検出部１１
と、基本波逆相分検出部１２と、地絡判定部１８とによ
り、本発明に係わる地絡検出装置が構成されている。In the example shown in FIG. 1, the three-phase AC detector 11
, The fundamental wave antiphase component detecting section 12 and the ground fault determining section 18 constitute a ground fault detecting apparatus according to the present invention.

【００７７】図４に示した配電系統に本発明を適用する
場合には、図１に示した基本波逆相分検出部１２と地絡
判定部１８とをネットワークプロテクタ４Ga〜４Gcのそ
れぞれに設けるとともに、ネットワークプロテクタ４Ga
〜４Gcにそれぞれに設けられた地絡判定部１８により高
圧配電線３ａ〜３ｃで地絡事故が発生したと判定された
ときに、遮断器制御部４Ea〜４Ecがそれぞれ遮断器４Da
〜４Dcに遮断指令を与えるようにしておく。When the present invention is applied to the distribution system shown in FIG. 4, the fundamental wave antiphase component detecting section 12 and the ground fault judging section 18 shown in FIG. 1 are provided in each of the network protectors 4Ga to 4Gc. With Network Protector 4Ga
-4Gc, when the ground fault determining unit 18 determines that a ground fault has occurred in the high-voltage distribution lines 3a-3c, the breaker control units 4Ea-4Ec respectively control the circuit breakers 4Da
A shutoff command is given to ~ 4Dc.

【００７８】同様に、常用予備受配電設備５にも基本波
逆相分検出部１２と地絡判定部１８とを設けるととも
に、地絡判定部１８により高圧配電線側で地絡事故が発
生したと判定されたときに、遮断器制御部５Ｅが遮断器
５Ｃに遮断指令を与えるように構成しておく。また遮断
器５Ｃに代えて、遮断器５Aaまたは５Abに遮断指令を与
えるようにしてもよい。Similarly, the normal standby power receiving and distribution equipment 5 is also provided with the fundamental wave antiphase component detecting section 12 and the ground fault judging section 18, and the ground fault judging section 18 causes a ground fault accident on the high voltage distribution line side. Is determined, the circuit breaker control unit 5E is configured to give a circuit break command to the circuit breaker 5C. Further, a breaking command may be given to the circuit breaker 5Aa or 5Ab instead of the circuit breaker 5C.

【００７９】上記のように構成すると、例えば図４のＸ
点で地絡事故が生じて、高圧配電線３ａが変電所１の母
線１B1から切り離されたときに、ネットワーク受配電設
備では、遮断器制御部４Eaに設けられた地絡判定部が高
圧配電線３ａで地絡事故が発生したことを検出するた
め、プロテクタ遮断器４Daが開いて、変圧器４Baの高圧
側回路と低圧側回路とを切り離す。これにより、他の健
全な配電線３ｂ及び３ｃ側から変圧器４Bb及び４Bcとネ
ットワーク母線ＢＵＳ1 と変圧器４Baとを通して高圧配
電線３ａ側に逆電力の潮流が生じるのを防止することが
できる。With the above configuration, for example, X in FIG.
When a ground fault occurs at a point and the high voltage distribution line 3a is disconnected from the bus 1B1 of the substation 1, in the network power receiving and distribution equipment, the ground fault determination unit provided in the circuit breaker control unit 4Ea uses the high voltage distribution line. In order to detect the occurrence of the ground fault at 3a, the protector circuit breaker 4Da opens to disconnect the high-voltage side circuit and the low-voltage side circuit of the transformer 4Ba. Thereby, it is possible to prevent a reverse power flow from occurring on the high-voltage distribution line 3a side from the other healthy distribution lines 3b and 3c through the transformers 4Bb and 4Bc, the network bus BUS1, and the transformer 4Ba.

【００８０】また常用予備受配電設備でも、上記のよう
に構成すると、例えば図４のＸ点で地絡事故が生じて、
高圧配電線３ａが変電所１の母線１B1から切り離された
ときに、遮断器制御部５Ｅに設けられた地絡判定部が高
圧配電線３ａで地絡事故が発生したことを検出するた
め、遮断器５Ｃが開いて、変圧器５Ｂの高圧側回路と低
圧側回路とを切り離す。これにより、分散型電源Ｇ2 か
ら母線ＢＵＳ2 と変圧器５Ｂとを通して高圧配電線３ａ
側に逆電力の潮流が生じるのを防止することができる。In the normal standby power receiving and distributing equipment, if configured as described above, for example, a ground fault may occur at point X in FIG.
When the high-voltage distribution line 3a is disconnected from the bus 1B1 of the substation 1, the ground fault determination unit provided in the circuit breaker control unit 5E detects that a ground fault has occurred in the high-voltage distribution line 3a. The transformer 5C is opened to disconnect the high-voltage side circuit and the low-voltage side circuit of the transformer 5B. Thus, the high-voltage distribution line 3a is connected from the distributed power source G2 through the bus BUS2 and the transformer 5B.
A reverse power flow on the side can be prevented.

【００８１】本発明に係わる地絡検出装置は、低圧側に
例えば分散型電源を連系している受配電設備または他の
配電系統と連系している受配電設備に適用できる。The ground fault detecting device according to the present invention can be applied to a power receiving / distributing facility in which, for example, a distributed power supply is connected to a low voltage side or a power receiving / distributing facility in which another power distribution system is connected.

【００８２】[0082]

【発明の効果】以上のように、本発明によれば、配電系
統に設けられている各受電用変圧器の低圧側の回路でそ
の回路がつながる高圧配電線で地絡事故が発生したこと
を検出することができるため、受電用変圧器と高圧配電
線との間の回路の構成を簡素にするという要請に応えつ
つ、各受配電設備で高圧配電線の地絡事故を検出して、
事故が生じた高圧配電線につながる回線を該高圧配電線
から切り離すなどの措置を講じることができる利点があ
る。As described above, according to the present invention, the occurrence of a ground fault in a high-voltage distribution line to which a low-voltage circuit of each power receiving transformer provided in a distribution system is connected. In response to the request to simplify the circuit configuration between the receiving transformer and the high-voltage distribution line, it is possible to detect the ground fault of the high-voltage distribution line at each power receiving and distribution facility,
There is an advantage that it is possible to take measures such as disconnecting the line connected to the high-voltage distribution line where the accident has occurred from the high-voltage distribution line.

【００８３】また本発明のように受配電設備を構成すれ
ば、該受配電設備内で高圧配電線側の回路の地絡事故を
検出することができるため、地絡事故が検出された高圧
配電線につながる受電用変圧器の高圧側の回路と低圧側
の回路とを切り離して、事故が生じた高圧配電線への給
電を停止するなどの措置を迅速に講じることができる。If the power receiving and distribution equipment is configured as in the present invention, a ground fault in the circuit on the high voltage distribution line side can be detected in the power receiving and distribution equipment. The high-voltage side circuit and the low-voltage side circuit of the power receiving transformer connected to the electric wire can be separated from each other, and measures such as stopping power supply to the high-voltage distribution line in which the accident has occurred can be taken promptly.

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

【図１】本発明に係わる地絡検出装置の構成例を示した
ブロック図である。FIG. 1 is a block diagram showing a configuration example of a ground fault detecting device according to the present invention.

【図２】本発明に係わる地絡検出装置を説明するために
用いるベクトル図である。FIG. 2 is a vector diagram used to explain the ground fault detecting device according to the present invention.

【図３】本発明に係わる地絡検出装置を説明するために
用いるベクトル図である。FIG. 3 is a vector diagram used to explain the ground fault detecting device according to the present invention.

【図４】本発明を適用する配電系統の構成例を示した回
路図である。FIG. 4 is a circuit diagram showing a configuration example of a distribution system to which the present invention is applied.

【符号の説明】[Explanation of symbols]

１ 電源変電所 ３ａ〜３ｄ 配電線 ４ ネットワーク受配電設備 ４Aa〜４Ac 断路器 ４Ba〜４Bc ネットワーク変圧器 ４Da〜４Dc プロテクタ遮断器 ４Ea〜４Ec 遮断器制御部 ＢＵＳ1 ネットワーク母線 １１ ３相交流検出部 １２ 基本波逆相分検出部 １８ 地絡判定部 DESCRIPTION OF SYMBOLS 1 Power substation 3a-3d Distribution line 4 Network power distribution equipment 4Aa-4Ac Disconnector 4Ba-4Bc Network transformer 4Da-4Dc Protector breaker 4Ea-4Ec Breaker control unit BUS1 Network bus 11 Three-phase AC detector 12 Basic wave Negative phase detector 18 Ground fault detector

───────────────────────────────────────────────────── フロントページの続き (72)発明者 橋本 隆 大阪府大阪市淀川区田川２丁目１番11号 株式会社ダイヘン内 (72)発明者 遠藤 淳 大阪府大阪市淀川区田川２丁目１番11号 株式会社ダイヘン内 (72)発明者 栗山 忠士 大阪府大阪市淀川区田川２丁目１番11号 株式会社ダイヘン内 (72)発明者 乾 正博 大阪府大阪市淀川区田川２丁目１番11号 株式会社ダイヘン内 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Takashi Hashimoto 2-1-1-11 Tagawa, Yodogawa-ku, Osaka, Osaka Prefecture (72) Inventor Jun Endo 2-1-1, Tagawa, Yodogawa-ku, Osaka-shi, Osaka No. Daihen Co., Ltd. (72) Inventor Tadashi Kuriyama 2-1-1-11 Tagawa, Yodogawa-ku, Osaka-shi, Osaka Daisen Co., Ltd. (72) Masahiro Inui 2-1-1-11 Tagawa, Yodogawa-ku, Osaka-shi, Osaka In company Daihen

Claims (5)

【特許請求の範囲】[Claims] 【請求項１】 電源変電所から引き出された高圧配電線
に絶縁変圧器からなる受電用変圧器を備えた受配電設備
が接続されている配電系統の前記高圧配電線で地絡事故
が生じたことを前記受配電設備で検出する地絡検出装置
において、 前記受電用変圧器の低圧側の回路を流れる３相交流電流
を検出する３相交流検出部と、 前記３相交流検出部により検出された３相交流電流の基
本波の逆相分を検出する基本波逆相分検出部と、 前記基本波逆相分検出部により検出された逆相分から地
絡事故の発生の有無を判定する地絡判定部と、 を具備したことを特徴とする配電系統の地絡検出装置。1. A ground fault has occurred in a high-voltage distribution line of a power distribution system in which a high-voltage distribution line drawn from a power substation is connected to a power receiving and distribution facility having a power receiving transformer including an insulating transformer. A ground fault detecting device that detects the three-phase alternating current flowing through the low-voltage side circuit of the power receiving transformer; and a three-phase alternating current detector that detects the three-phase alternating current. A fundamental-wave negative-phase-sequence detecting unit for detecting the negative-phase component of the fundamental wave of the three-phase alternating current; A ground fault detecting device for a distribution system, comprising: a ground fault determining unit. 【請求項２】 前記基本波逆相分検出部は、 前記３相交流検出部により検出された３相交流電流を３
軸静止座標系におけるベクトル量として扱って該３軸静
止座標系における３相交流電流を、２軸が互いに直交す
る２軸静止座標系における２相交流電流に変換する３相
／２相変換部と、 前記２軸静止座標系を前記２相交流電流の基本波正相分
の相回転方向または基本波逆相分の相回転方向に回転す
る第１の２軸回転座標系に変換することにより前記２相
交流電流の基本波正相分及び基本波逆相分の一方を直流
電流に変換し、他方を基本波周波数の２倍の周波数の交
流電流に変換する第１の回転座標変換部と、 前記第１の回転座標変換部の出力から２相交流電流の基
本波正相分を除去して基本波逆相分を抽出するフィルタ
手段と、 前記第１の２軸回転座標系を該第１の２軸回転座標系と
逆方向に回転する第２の２軸回転座標系に変換すること
により、前記フィルタ手段により抽出された２相交流電
流の基本波逆相分を２軸静止座標系における２相交流電
流の基本波逆相分に逆変換する第２の回転座標変換部と
を備え、 前記第２の回転座標変換部から得られる２相交流電流の
基本波逆相分、または該２相交流電流の基本波逆相分を
２相／３相変換することにより得た３相交流電流の基本
波逆相分を前記基本波逆相分検出部の検出出力として用
いることを特徴とする請求項１に記載の地絡検出装置。2. The three-phase alternating current detected by the three-phase alternating current detecting unit, the three-phase alternating current detected by the three-phase alternating current detecting unit.
A three-phase / two-phase converter for treating a three-phase alternating current in the three-axis stationary coordinate system into a two-phase alternating current in a two-axis stationary coordinate system in which two axes are orthogonal to each other by treating as a vector quantity in the axial stationary coordinate system; Converting the two-axis stationary coordinate system into a first two-axis rotating coordinate system that rotates in the phase rotation direction of the fundamental wave positive phase or the fundamental wave negative phase of the two-phase AC current. A first rotational coordinate conversion unit that converts one of the fundamental wave positive phase component and the fundamental wave negative phase component of the two-phase AC current into a DC current, and converts the other into an AC current having a frequency twice the fundamental frequency; Filter means for removing the positive-phase component of the fundamental wave of the two-phase alternating current from the output of the first rotary coordinate conversion unit and extracting the negative-phase component of the fundamental wave; To a second two-axis rotating coordinate system that rotates in the opposite direction to the two-axis rotating coordinate system A second rotational coordinate conversion unit for inversely converting the two-phase alternating current fundamental wave reverse phase component extracted by the filter means into the two-phase alternating current fundamental wave negative phase component in the two-axis stationary coordinate system. A three-phase alternating current obtained by subjecting the two-phase alternating current obtained from the second rotating coordinate converter to a two-phase / three-phase conversion of the fundamental phase opposite phase component of the two-phase alternating current or the two-phase alternating current fundamental phase opposite phase component. 2. The ground fault detecting device according to claim 1, wherein a negative-phase component of a current is used as a detection output of the negative-phase component detection unit. 3. 【請求項３】 電源変電所から引き出された高圧配電線
に高圧側が接続された絶縁変圧器からなる受電用変圧器
と該受電用変圧器の高圧側の回路または低圧側の回路を
開閉する遮断器とを備えた受配電設備において、 前記受電用変圧器の低圧側の回路に設けられて該受電用
変圧器を通して流れる３相交流電流を検出する変流器
と、 前記変流器により検出された３相交流電流の基本波の逆
相分を検出する基本波逆相分検出部と、 前記基本波逆相分検出部により検出された逆相分から前
記受電用変圧器につながる前記高圧配電線側の回路で地
絡事故が発生したか否かを判定する地絡判定部と、 前記地絡判定部が地絡事故が発生したと判定した時に前
記遮断器に遮断指令を与える遮断器制御部と、 を具備したことを特徴とする受配電設備。3. A power receiving transformer comprising an insulating transformer having a high voltage side connected to a high voltage distribution line drawn from a power substation, and a circuit for opening and closing a high voltage side circuit or a low voltage side circuit of the power receiving transformer. A current transformer provided in a low-voltage side circuit of the power receiving transformer and detecting a three-phase alternating current flowing through the power receiving transformer; and And a high-voltage distribution line connected to the power receiving transformer from a negative-phase component detected by the basic-wave negative-phase component detection unit. A ground fault determining unit that determines whether a ground fault has occurred in the circuit on the side; and a circuit breaker control unit that provides a break command to the circuit breaker when the ground fault determining unit determines that a ground fault has occurred. A power receiving and distribution facility, comprising: 【請求項４】 電源変電所から引き出された複数の高圧
配電線にそれぞれ高圧側が接続された絶縁変圧器からな
る複数のネットワーク変圧器と、前記複数のネットワー
ク変圧器に対して共通に設けられたネットワーク母線
と、各ネットワーク変圧器の低圧側と前記ネットワーク
母線との間に設けられたネットワークプロテクタとを備
え、 前記ネットワークプロテクタは、対応するネットワーク
変圧器の低圧側と前記ネットワーク母線との間に設けら
れたプロテクタ遮断器と、対応するネットワーク変圧器
の低圧側の回路を流れる電流を検出する変流器と、対応
するネットワーク変圧器の低圧側から高圧側に逆電力の
潮流が生じたことを検出した時に前記プロテクタ遮断器
を開くネットワーク継電器とを備えている受配電設備に
おいて、 前記ネットワークプロテクタは、 前記変流器が検出した３相交流電流の基本波の逆相分を
検出する基本波逆相分検出部と、 前記基本波逆相分検出部が検出した逆相分から対応する
ネットワーク変圧器につながる前記高圧配電線側の回路
で地絡事故が発生したか否かを判定する地絡判定部と、 前記地絡判定部が地絡事故が発生したと判定したときに
前記プロテクタ遮断器に遮断指令を与える遮断器制御部
と、 を具備したことを特徴とする受配電設備。4. A plurality of network transformers each including an insulating transformer having a high-voltage side connected to a plurality of high-voltage distribution lines drawn from a power substation, and provided in common to the plurality of network transformers. A network protector provided between the low voltage side of each network transformer and the network bus, wherein the network protector is provided between the low voltage side of the corresponding network transformer and the network bus. Current detector that detects the current flowing in the low-voltage side circuit of the corresponding network transformer, and that the reverse power flow from the low-voltage side to the high-voltage side of the corresponding network transformer has been detected. And a network relay that opens the protector breaker when the power is received. A network protector configured to detect a negative phase component of the fundamental wave of the three-phase AC current detected by the current transformer, and a negative phase component detected by the negative phase component of the fundamental wave. A ground fault determining unit that determines whether a ground fault has occurred in a circuit on the high voltage distribution line connected to a network transformer; and the protector when the ground fault determining unit determines that a ground fault has occurred. A power receiving and distribution facility, comprising: a circuit breaker control unit for giving a break command to the circuit breaker. 【請求項５】 前記基本波逆相分検出部は、 前記変流器により検出された３相交流電流を３軸静止座
標系におけるベクトル量として扱って該３軸静止座標系
の３相交流電流を、２軸が互いに直交する２軸静止座標
系における２相交流電流に変換する３相／２相変換部
と、 前記２軸静止座標系を前記２相交流電流の基本波正相分
の相回転方向または基本波逆相分の相回転方向に回転す
る第１の２軸回転座標系に変換することにより前記２相
交流電流の基本波正相分及び基本波逆相分の一方を直流
電流に変換し、他方を基本波周波数の２倍の周波数の交
流電流に変換する第１の回転座標変換部と、 前記第１の回転座標変換部の出力から２相交流電流の基
本波正相分を除去して基本波逆相分を抽出するフィルタ
手段と、 前記第１の２軸回転座標系を該第１の２軸回転座標系と
逆方向に回転する第２の２軸回転座標系に変換すること
により、前記フィルタ手段により抽出された２相交流電
流の基本波逆相分を２軸静止座標系における２相交流電
流の基本波逆相分に逆変換する第２の回転座標変換部と
を備え、 前記第２の回転座標変換部から得られる２相交流電流の
基本波逆相分、または該２相交流電流の基本波逆相分を
２相／３相変換することにより得た３相交流電流の基本
波逆相分を前記基本波逆相分検出部の検出出力として用
いることを特徴とする請求項３または４に記載の受配電
設備。5. The three-phase alternating current of the three-axis stationary coordinate system by treating the three-phase alternating current detected by the current transformer as a vector quantity in the three-axis stationary coordinate system. To a two-phase alternating current in a two-axis stationary coordinate system in which two axes are orthogonal to each other, and a phase corresponding to a fundamental wave positive phase of the two-phase alternating current in the two-axis stationary coordinate system. By converting into a first biaxial rotating coordinate system that rotates in the rotation direction or the phase rotation direction of the fundamental wave reverse phase, one of the fundamental wave positive phase component and the fundamental wave negative phase component of the two-phase AC current is converted into a DC current. A first rotating coordinate converter for converting the other into an alternating current having a frequency twice as high as the fundamental frequency, and a fundamental wave positive phase component of the two-phase alternating current from the output of the first rotating coordinate converter. Filter means for removing the phase component of the fundamental wave by removing the first two-axis coordinate system; By converting into a second two-axis rotating coordinate system rotating in a direction opposite to the first two-axis rotating coordinate system, the two-phase AC current extracted by the filter means is subjected to two-axis stationary phase components. A second rotational coordinate conversion unit that performs an inverse conversion of the two-phase alternating current in the coordinate system into a negative-phase component of the two-phase alternating current. Alternatively, the fundamental wave reversed phase component of the three-phase alternating current obtained by subjecting the fundamental wave reversed phase component of the two-phase alternating current to two-phase / three-phase conversion is used as the detection output of the fundamental wave reversed-phase component detection unit. The power receiving and distribution facility according to claim 3 or 4, wherein