JPH0515132B2 - - Google Patents
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- Publication number
- JPH0515132B2 JPH0515132B2 JP59003018A JP301884A JPH0515132B2 JP H0515132 B2 JPH0515132 B2 JP H0515132B2 JP 59003018 A JP59003018 A JP 59003018A JP 301884 A JP301884 A JP 301884A JP H0515132 B2 JPH0515132 B2 JP H0515132B2
- Authority
- JP
- Japan
- Prior art keywords
- current
- power transmission
- transmission line
- electrical system
- branch point
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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- 238000001514 detection method Methods 0.000 claims description 33
- 230000007423 decrease Effects 0.000 claims description 27
- 230000005540 biological transmission Effects 0.000 description 65
- 238000010586 diagram Methods 0.000 description 6
- 238000009499 grossing Methods 0.000 description 4
- 238000004364 calculation method Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
Description
〔発明の利用分野〕
本発明は、電気系統の故障検出方式に係り、特
に分岐式直流多端子送電等の電気系統の故障検出
に好適な故障検出方式に関する。
〔発明の背景〕
従来行われている２端子直流送電における送電
線等の電気系統の事故検出の一方式を第１図によ
り説明する。第１図において、１０は直流送電
線、２１，２２は交流を直流に、または直流を交
流に変換する交直変換装置で、この場合、説明を
簡単にするために交直変換装置２１は交流を直流
に変換する順変換装置として、また２２は直流を
交流に変換するインバータ（逆変換装置）として
運転するものとする。３１，３２は直流電流を平
滑するための平滑リアクトルである。
このような２端子直流送電において送電線１０
の例えばｆ点で地絡事故が発生すると、送電線の
順変換装置２１の出力端側に設けられた直流電流
検出器CT１の電流Irは増加し、送電線１０のイ
ンバータ２２の入力端側に設けられた直流電流検
出器CT２の電流Iiは減少する。従つて、電流Iiの
減少時に動作する電流減少検出器４１と電流Irの
増加時に動作する電流増加検出器５１とを設け
て、これが同時に動作したことをアンド回路６１
で検出して故障検出を行う。この概略動作を第２
図のタイミングチヤートに示す。送電方向が逆と
なつた場合は、以上とは逆に電流Irが減少し、電
流Irが増加するので、直流電流検出器CT１の出
力端には電流減少検出器を直流電流検出器CT２
の出力端には電流増加検出器を設けて、これらの
出力の論理和をとることにより送電方向が逆とな
つた場合も検出が行える。
しかし、このような検出方式を第３図に示すよ
うな直流多端子送電の送電線に適用すると多数の
直流電流検出器を必要とし、また送電線が長い場
合には検出信号を送る高速の通信装置が必要不可
欠となるので好ましくない。
〔発明の目的〕
本発明の目的は上述した従来技術の問題点を解
消し、簡単な構成で高速な応答がえられ、かつ経
済的な電気系統の故障検出装置を提供することに
ある。
〔発明の概要〕
分岐式直流多端子送電等において送電線等の電
気系統の故障検出を行う場合、従来のように送電
線等の電気系統の両端に電流検出器を設けて電流
の増減を調べなくても、それぞれの送電線等の電
気系統の分岐点端にのみ電流検出器を設け、この
電流検出値の増減から送電線等の電気系統の故障
検出ができることが計算及びアナログシミユレー
タによるシミユレーシヨン結果から判つた。即
ち、送電線等の電気系統事故時の電流検出値の増
加、減少は運用系体（潮流方向）が決まると故障
が生じた送電線等の電気系統と１対１に対応す
る。
本発明は上記知見に基づいてなされたものであ
り、送電線等の電気系統の途中に分岐点をもつ直
流多端子系統において、分岐点における各送電線
等の電気系統の分岐点端の電流を検出し、これら
の個々の送電線等の電気系統の電流の増加、減少
状態から送電線等の電気系統の故障判別を行うこ
とを特徴とするものである。
〔発明の実施例〕
本発明の実施例を第３図乃至第７図に基づいて
説明する。第３図には分岐式直流多端子送電系統
の構成が示されており、同図において１１，１
２，１３は送電線、２１，２２，２３は交直変換
装置、３１，３２，３３は平滑リアクトル、CT
１〜CT３は分岐点Ｂにおける各送電線１１〜１
３の分岐点端における電流を検出する直流電流検
出器、１００は直流電流検出器１１〜１３の検出
出力及び交直変換器２１〜２３からの運転状態
（順変換器運転またはインバータ運転）を示す指
令Ｃ１〜Ｃ３を取り込み各送電線の故障を検出
し、故障判別信号f1〜f3を出力する故障検出回路
である。
交直変換装置２１，２３が順変換装置、２２が
インバータとして動作するときの送電線１１，１
２，１３の各点f1，f2，f3で地絡事故が生じた場
合の送電線の分岐点Ｂ端に設けた直流電流検出器
CT１〜CT３の検出値I1，I2，I3の増減を表１に
示す。
[Field of Application of the Invention] The present invention relates to a fault detection method for electrical systems, and particularly to a fault detection method suitable for fault detection in electrical systems such as branch type DC multi-terminal power transmission. [Background of the Invention] One method of detecting faults in electrical systems such as power transmission lines in conventional two-terminal DC power transmission will be explained with reference to FIG. In FIG. 1, 10 is a DC transmission line, and 21 and 22 are AC/DC converters that convert AC to DC or DC to AC. It is assumed that 22 is operated as a forward converter for converting direct current into alternating current, and as an inverter (inverse converter) for converting direct current into alternating current. 31 and 32 are smoothing reactors for smoothing direct current. In such two-terminal DC power transmission, the power transmission line 10
For example, when a ground fault occurs at point f, the current Ir of the DC current detector CT1 installed at the output end of the forward converter 21 of the power transmission line increases, and The current I i of the DC current detector CT2 provided at the DC current detector CT2 decreases. Therefore, a current decrease detector 41 that operates when the current I i decreases and a current increase detector 51 that operates when the current I r increases are provided, and the AND circuit 61 detects that they operate simultaneously.
Detection is performed to detect failures. This general operation is explained in the second
This is shown in the timing chart in the figure. When the power transmission direction is reversed, the current I r decreases and the current I r increases, contrary to the above, so a current decrease detector is connected to the output terminal of the DC current detector CT1, and a current decrease detector is connected to the DC current detector CT2.
A current increase detector is provided at the output end of the detector, and by calculating the logical sum of these outputs, it is possible to detect even when the power transmission direction is reversed. However, if such a detection method is applied to a DC multi-terminal power transmission line as shown in Figure 3, it will require a large number of DC current detectors, and if the transmission line is long, it will require high-speed communication to send the detection signal. This is not preferable because the equipment becomes indispensable. [Object of the Invention] An object of the present invention is to solve the problems of the prior art described above, and to provide an economical electrical system failure detection device that has a simple configuration, can provide a high-speed response, and is economical. [Summary of the invention] When detecting failures in electrical systems such as power transmission lines in branch-type DC multi-terminal power transmission, etc., current detectors are installed at both ends of the electrical system such as power transmission lines to check for increases and decreases in current, as in the past. Calculations and analog simulators have shown that even if there is no current detector, it is possible to install a current detector only at the branch point end of each electrical system such as a power transmission line, and detect a failure in the electrical system such as a power transmission line based on the increase or decrease in the detected current value. This was determined from the simulation results. That is, when the operating system (current direction) is determined, the increase or decrease in the detected current value at the time of a fault in an electrical system such as a power transmission line corresponds one-to-one with the electrical system such as a power transmission line in which a failure has occurred. The present invention has been made based on the above knowledge, and it is a DC multi-terminal system that has branch points in the middle of an electrical system such as a power transmission line. The present invention is characterized in that a fault in an electrical system such as a power transmission line is determined based on the increase or decrease state of current in each electrical system such as a power transmission line. [Embodiments of the Invention] Examples of the present invention will be described based on FIGS. 3 to 7. Figure 3 shows the configuration of a branch type DC multi-terminal power transmission system.
2, 13 are power transmission lines, 21, 22, 23 are AC/DC converters, 31, 32, 33 are smoothing reactors, CT
1 to CT3 are each power transmission line 11 to 1 at branch point B
A DC current detector detects the current at the branch point end of No. 3, and 100 is a command indicating the detection output of the DC current detectors 11 to 13 and the operating state (forward converter operation or inverter operation) from the AC/DC converters 21 to 23. This is a failure detection circuit that takes in C1 to C3, detects a failure in each power transmission line, and outputs failure determination signals f1 to f3 . Transmission lines 11 and 1 when AC/DC converters 21 and 23 operate as forward converters and 22 operates as an inverter
DC current detector installed at the branch point B end of the power transmission line in case a ground fault occurs at each point f 1 , f 2 , f 3 of 2 and 13
Table 1 shows increases and decreases in detected values I 1 , I 2 , and I 3 of CT1 to CT3.
【表】
表中＋は電流の増加、−は減少を示す。例えば
送電線１１の地絡故障時は送電線１１の分岐点端
に設けられた電流検出器CT１の出力電流I1及び
送電線１２の電流検出器CT２の出力電流I2は減
少し、送電線１３の電流検出器CT３の出力電流
I3は増加する。この出力電流の増減は直流系統の
運用系体（潮流方向）が決まると送電線事故とは
１対１に対応するので表１に示すような電流検出
値の増減パターンを用いて、送電線の故障検出を
行うことができる。
表１の場合におけるf1（送電線１１の故障）、f2
（送電線１２の故障）、及びf3（送電線の１３の故
障）を出力する故障検出装置を第４図に示す。同
図において入力のI1，I2，及びI3は送電線１１，
１２，１３の送電線の分岐点端に設けられた電流
検出器CT１〜CT３の検出値である。４１，４
２，４３はそれぞれ、電流I1，I2，I3の減少状態
を検出する電流減少検出回路、５１，５２，５３
はそれぞれ電流I1，I2，I3の電流増加状態を検出
する電流増加検出回路でいずれも電流の減少状態
または増加状態が検出されたとき的とな幅の論理
“１”信号を出力する。６１，６２，６３はアン
ド回路で、アンド回路６１は電流I1及びI2が減少
し、電流I3が増加したときにアンド条件が満たさ
れ、論理“１”信号を出力する。従つて送電線１
１における故障を検出することができる。同様に
アンド回路６２は電流I1，I2及びI3が増加したと
きアンド条件が満たされ論理“１”信号を出力す
る。従つて送電線１２における故障が検出でき
る。またアンド回路６３はI1が増加し、且つ電流
I2及びI3が減少したときアンド条件が満たされる
ので、このとき論理“１”信号を出力し、送電線
１３の故障検出が行われる。
以上の故障検出装置では各送電線の分岐点端に
電流検出器を設け、この検出値の増減から送電線
の故障を検出するものであつたが、更に簡単に第
３図に示した直流送電系統の場合には２つの送電
線の分岐点端に設けられた電流検出器の検出値か
ら送電線の故障を検出できる。これは電流の大き
さと方向を考えると、
I1＋I2＋I3＝０
となり、３分岐の場合は二つの電流検出値から他
の電流検出値が求まることによる。例えば、第３
図において送電線１１の分岐点端に設けられた電
流検出器の検出値I1と送電線１２の電流検出値I2
とから、送電線の故障を検出する場合の故障検出
装置を第５図に示す。図中、第４図と同じ番号の
ものは同じ回路である。アンド回路７１はI1の減
少とI2の減少により出力“１”を出し、従つて送
電線１１の故障が検出できる。アンド回路７２は
I1の増加とI2の増加により出力“１”を出すため
送電線１２の故障検出が行える。また、アンド回
路７３はI1の増加、I2の減少により出力“１”を
出すため送電線１３の故障検出が行える。
このように第４図に比較して回路構成が簡単で
あり、経済的である。
尚、送電線故障時と変換所内の事故、例えば変
換器の転流失敗等とは送電線の電流の増減状態が
異なるので、変換所内の事故とは区別して送電線
の故障を検出することができる。
以上、直流送電線の分岐が３分岐の場合につい
て説明したが、分岐数が増加した場合も以上で述
べたと同様に、各々の送電線の分岐点端に電流検
出器を設け、送電線事故によるこの電流検出器の
増減が運用系体（潮流の方向）によつて一義的に
決まるので、前もつて増減のパターンに従つて故
障検出装置を構成することにより検出できる。ま
た、第６図に示すように分岐点が２ケ所、または
それ以上から成る場合も、各々の分岐点B1，B2
において上述したと同様にして直流電流検出器
CT１〜CT６及び故障検出装置１００，１０１を
構成することにより送電線の故障検出を行うこと
ができる。
尚、以上の説明では直流系の潮流方向が一定の
場合に限つて説明したが、潮流方向が変化しても
電流増減は前もつてパターン化できるので、これ
により簡単に検出できる。例えば第３図において
直流変換装置２３が順変換器、２１，２２がイン
バータとなつた場合は事故時の電流増減のパター
ンは表２のようになる。[Table] In the table, + indicates an increase in current, and - indicates a decrease. For example, when a ground fault occurs in the power transmission line 11, the output current I1 of the current detector CT1 provided at the branch point end of the power transmission line 11 and the output current I2 of the current detector CT2 of the power transmission line 12 decrease, and the power transmission line Output current of 13 current detector CT3
I 3 increases. This increase/decrease in output current has a one-to-one correspondence with a transmission line fault once the operating system (power flow direction) of the DC system is determined. Failure detection can be performed. f 1 (failure of power transmission line 11), f 2 in the case of Table 1
FIG. 4 shows a failure detection device that outputs f 3 (fault in power transmission line 12) and f 3 (failure in power transmission line 13). In the same figure, the inputs I 1 , I 2 , and I 3 are the transmission line 11,
These are detection values of current detectors CT1 to CT3 provided at the branch point ends of power transmission lines No. 12 and 13. 41,4
2 and 43 are current reduction detection circuits that detect the reduction state of currents I 1 , I 2 , and I 3 , respectively; 51 , 52 , and 53 ;
are current increase detection circuits that detect the increasing state of the currents I 1 , I 2 , and I 3 , and each outputs a logic “1” signal with a specific width when a decreasing state or increasing state of the current is detected. . 61, 62, and 63 are AND circuits, and the AND circuit 61 satisfies the AND condition when currents I 1 and I 2 decrease and current I 3 increases, and outputs a logic "1" signal. Therefore, transmission line 1
1 can be detected. Similarly, when the currents I 1 , I 2 and I 3 increase, the AND condition is satisfied and the AND circuit 62 outputs a logic "1" signal. Therefore, a fault in the power transmission line 12 can be detected. In addition, the AND circuit 63 increases I 1 and the current
Since the AND condition is satisfied when I 2 and I 3 decrease, a logic "1" signal is output at this time, and a fault in the power transmission line 13 is detected. In the above fault detection device, a current detector is installed at the branch point end of each power transmission line, and a fault in the power transmission line is detected from an increase or decrease in the detected value. In the case of a power grid, a failure in a power transmission line can be detected from the detected value of a current detector provided at the branch point end of two power transmission lines. This is because when considering the magnitude and direction of the current, I 1 +I 2 +I 3 =0, and in the case of three branches, another current detection value is determined from the two current detection values. For example, the third
In the figure, the detected value I 1 of the current detector installed at the branch point end of the power transmission line 11 and the detected current value I 2 of the power transmission line 12
FIG. 5 shows a failure detection device for detecting failures in power transmission lines. In the figure, the same numbers as in FIG. 4 are the same circuits. The AND circuit 71 outputs "1" due to the decrease in I 1 and the decrease in I 2 , and therefore, a failure in the power transmission line 11 can be detected. AND circuit 72
An increase in I 1 and an increase in I 2 produce an output of "1", so a failure in the power transmission line 12 can be detected. Further, since the AND circuit 73 outputs an output "1" due to an increase in I 1 and a decrease in I 2 , it is possible to detect a failure in the power transmission line 13 . As described above, the circuit configuration is simpler and more economical than that shown in FIG. Furthermore, since the increase/decrease state of the current in the transmission line is different between a power transmission line failure and an accident inside a converter station, such as a converter commutation failure, it is not possible to detect a power transmission line failure separately from an accident inside a converter station. can. Above, we have explained the case where the DC transmission line has three branches, but even when the number of branches increases, a current detector is installed at the branch point end of each transmission line, and it is necessary to Since the increase/decrease in the current detector is uniquely determined by the operating system (the direction of the current), it can be detected by configuring the failure detection device in advance according to the pattern of increase/decrease. Also, when there are two or more branch points as shown in Fig. 6, each branch point B 1 , B 2
DC current detector in the same manner as described above.
By configuring CT1 to CT6 and failure detection devices 100 and 101, it is possible to detect failures in power transmission lines. Note that the above explanation has been made only for the case where the direction of power flow in the DC system is constant, but even if the direction of power flow changes, the increase and decrease in current can be patterned in advance, so it can be easily detected. For example, in FIG. 3, if the DC converter 23 is a forward converter and 21 and 22 are inverters, the pattern of current increase and decrease in the event of an accident will be as shown in Table 2.
本発明では従来における送電線故障検出装置の
ように、送電線の両端に電流検出器を設ける必要
がないため、信号のやりとりのための通信装置は
必要なく、低コストで信頼性の高い電気系統故障
検出方式が得られる。
尚、以上の説明では送電線を分岐した電気系統
の場合について説明したが、送電線に限らず直流
線が分岐している箇所、例えば周波数変換所にも
適用できることは明らかである。
Unlike conventional power transmission line fault detection devices, the present invention does not require current detectors to be provided at both ends of the power transmission line, so there is no need for a communication device for exchanging signals, and the electrical system can be installed at low cost and with high reliability. A fault detection method is obtained. In the above description, the case of an electrical system with branched power transmission lines has been described, but it is clear that the present invention can be applied not only to power transmission lines but also to locations where DC lines branch off, such as frequency conversion stations.
第１図は２端子直流送電系統における送電線の
故障検出の従来方式を示すブロツク図、第２図は
第１図における各部の動作状態を示すフローチヤ
ート、第３図は本発明が適用される分岐式直流多
端子送電系統の構成図、第４図は３図における故
障検出回路の構成を示すブロツク図、第５図は故
障検出回路の他の構成例を示すブロツク図、第６
図は本発明が適用される分岐式直流多端子送電系
統の他の例を示す構成図、第７図は送電系統の潮
流方向の変化を考慮した故障検出回路の構成を示
すブロツク図である。
１０〜１４……送電線、２１〜２４……交直変
換装置、３１〜３４……平滑リアクトル、CT１
〜CT６……直流電流検出器、４１〜４３……電
流減少検出回路、５１〜５３……電流増加検出回
路、６１〜６３，７１〜７３……アンド回路、８
１，８２……切替回路、１００，１０１……故障
検出回路。
Fig. 1 is a block diagram showing a conventional method for detecting faults in transmission lines in a two-terminal DC transmission system, Fig. 2 is a flowchart showing the operating status of each part in Fig. 1, and Fig. 3 is a diagram to which the present invention is applied. FIG. 4 is a block diagram showing the configuration of the fault detection circuit in FIG. 3. FIG. 5 is a block diagram showing another example of the structure of the fault detection circuit.
This figure is a block diagram showing another example of a branch type DC multi-terminal power transmission system to which the present invention is applied, and FIG. 7 is a block diagram showing the structure of a failure detection circuit that takes into account changes in the power flow direction of the power transmission system. 10-14...Power transmission line, 21-24...AC/DC converter, 31-34...Smoothing reactor, CT1
~CT6...DC current detector, 41-43...Current decrease detection circuit, 51-53...Current increase detection circuit, 61-63, 71-73...AND circuit, 8
1, 82...Switching circuit, 100, 101...Failure detection circuit.
Claims (1)
において、分岐点における各電気系統の分岐点端
の電流を検出する手段と、該電流検出手段の検出
出力を取り込み、電気系統の運用条件で定まる事
故時の各電気系統の分岐点端の潮流方向と事故電
気系統との関係に応じて定まる各電気系統の分岐
点端における電流増減変化の組合せパターンに基
づいて、事故の電気系統を判定する故障検出回路
と具備することを特徴とする電気系統の故障点検
出方式。 ２ 前記電流検出手段は分岐点における電気系統
の総数より１本、少ない数の各電気系統の分岐点
端の電流を検出することを特徴とする特許請求の
範囲第１項に記載の電気系統の故障点検出方式。[Scope of Claims] 1. In a DC multi-terminal system having a branch point in the middle of the electrical system, means for detecting the current at the branch point end of each electrical system at the branch point, and a detection output of the current detecting means is taken in and the electrical Based on the combination pattern of current increase/decrease at the branch point of each electrical system, which is determined according to the relationship between the power flow direction at the branch point of each electrical system at the time of an accident and the fault electrical system, which is determined by the operating conditions of the system, A fault point detection method for an electrical system, characterized by comprising a fault detection circuit for determining the electrical system. 2. The electrical system according to claim 1, wherein the current detection means detects the current at the branch point end of each electrical system whose number is one less than the total number of electrical systems at the branch point. Fault point detection method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59003018A JPS60148321A (en) | 1984-01-11 | 1984-01-11 | Defect detecting system of electric system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59003018A JPS60148321A (en) | 1984-01-11 | 1984-01-11 | Defect detecting system of electric system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60148321A JPS60148321A (en) | 1985-08-05 |
| JPH0515132B2 true JPH0515132B2 (en) | 1993-02-26 |
Family
ID=11545591
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59003018A Granted JPS60148321A (en) | 1984-01-11 | 1984-01-11 | Defect detecting system of electric system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60148321A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6258832A (en) * | 1985-09-05 | 1987-03-14 | 株式会社東芝 | Dc multi-terminal transmission system |
| JP2008075401A (en) * | 2006-09-25 | 2008-04-03 | Jfe Metal Products & Engineering Inc | Bracket body for guard fence, and guard fence |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5950730A (en) * | 1982-09-16 | 1984-03-23 | 株式会社日立製作所 | Multiterminal dc transmitter |
-
1984
- 1984-01-11 JP JP59003018A patent/JPS60148321A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5950730A (en) * | 1982-09-16 | 1984-03-23 | 株式会社日立製作所 | Multiterminal dc transmitter |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60148321A (en) | 1985-08-05 |
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