JPH0295132A - Current differential protective relaying device - Google Patents

Abstract

PURPOSE:To preferentially short-circuit effectively even in case of accidents of two or more phases in which the operation of an own terminal insufficient voltage relay cannot be expected by receiving the operating condition of an opponent terminal insufficient voltage relay, and generally judging the responses of the own terminal insufficient voltage relay and the opponent terminal insufficient voltage relay. CONSTITUTION:An own terminal preferential short-circuit is employed under the condition that accidents of one or more phases are detected from the elements of own terminal short-circuit insufficient voltage relay 6 and opponent terminal short-circuit insufficient voltage relay 21. Accordingly, if the relay 21 is operated, OR logics 11b, 11a attains '1' level, and the output of NOT logic 12 attains '0' level. Thus, the output of AND logic 13 is locked. Even in case of an incorrect response of a ground-fault current differential relay 5a, unnecessary tripping can be effectively stopped. Thus, a preferential short- circuit can be employed even in case of an accident in which the relay 6 cannot be operated by the operation of the relay 21.

Description

【発明の詳細な説明】 ［発明の目的］ （産業上の利用分野） 本発明は、抵抗接地系に適用される電流差動保護継電装
置、特に２相以上の地絡事故時に短絡優先とする方式に
おいて、事故点の位置に関係なく確実に短絡優先とする
ことが可能な電流差動保護継電装置に関する。[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention is a current differential protection relay device applied to a resistance grounding system, and particularly a current differential protection relay device that provides short-circuit priority in the event of a ground fault of two or more phases. The present invention relates to a current differential protection relay device that can reliably give priority to short circuits regardless of the location of the fault point.

（従来の技術） 抵抗接地系に用いられる電流差動保護継電装置において
、２相以上にまたがる地絡事故発生時には短絡相当の大
電流が流れるため、ＣＴ誤差等により地絡電流差動リレ
ーが不正応動上阻止することを目的として、相間電圧を
導入しな難路不足電圧リレーを設け、２相以上の事故時
には、地絡電流差動リレーをロックする、所謂短絡優先
方式が適用されるのが一般的である。(Prior art) In a current differential protection relay device used in a resistive grounding system, when a ground fault that spans two or more phases occurs, a large current equivalent to a short circuit flows, so the ground fault current differential relay is A so-called short-circuit priority method is applied, in which an undervoltage relay is installed that does not introduce phase-to-phase voltage in order to prevent false responses, and in the event of an accident involving two or more phases, the ground fault current differential relay is locked. is common.

以下、従来の抵抗接地系電流差動継電装置の例を第２図
、第３図を用いて説明する。第２図は抵抗接地系の系統
図を示しており、Ａ、ＢはそれぞれＡ電気所、Ｂ電気所
、１＾、　ＩＢは母線、２は３相表現の送電線、３はＣ
Ｔ、４は母線ＰＴ、５は電流差動リレー、６は短絡不足
電圧リレー、７は地絡過電圧リレー、Ｆは地絡事故点を
示す。なお、図には示していないが、Ｂ電気所にも上述
と同様の各リレーが設けられているものとする。An example of a conventional resistance grounding type current differential relay device will be described below with reference to FIGS. 2 and 3. Figure 2 shows a system diagram of a resistive grounding system, where A and B are electrical stations A and B, respectively, 1^, IB is a bus bar, 2 is a three-phase power transmission line, and 3 is C
T, 4 indicates bus line PT, 5 indicates current differential relay, 6 indicates short circuit undervoltage relay, 7 indicates ground fault overvoltage relay, and F indicates ground fault point. Although not shown in the figure, it is assumed that the B electric station is also provided with relays similar to those described above.

第３図はＡ電気所に設けられた電流差動継電装置の地絡
用外し、ブロック図を示しており、Ｂ電気所にも同様装
置が設けられている。５ａは地絡電流差動リレー、６は
短絡不足電圧リレー、７は地絡過電圧リレー、１１はＯ
Ｒ論理、１２はＮＯＴ論理、１３はＡＮＤ論理を示す。FIG. 3 shows a block diagram of a current differential relay device installed at electric station A for removing ground faults, and a similar device is also installed at electric station B. 5a is a ground fault current differential relay, 6 is a short circuit undervoltage relay, 7 is a ground fault overvoltage relay, 11 is O
R logic, 12 indicates NOT logic, and 13 indicates AND logic.

第２図において、Ａ電気所に対し、Ｒ８相の２相地絡事
故が遠方外部のＦ点にて発生した場合、遠方事故のため
Ａ電気所の電圧が十分に降下せず＠絡不足電圧リレー６
が動作できないことが考えられる。この場合、第３図の
引外しブロック図において短絡不足電圧リレーが不動作
となり、その各相出力のＯＲ論理１１の出力はＯレベル
、よってＮＯＴ論理１２の出力がルベルとなる。In Figure 2, when a 2-phase ground fault occurs in the R8 phase at point F, which is far outside the A electrical station, the voltage at the A electrical station will not drop sufficiently due to the distant fault, and the voltage at the A electrical station will not drop sufficiently. relay 6
It is possible that it is not working. In this case, in the tripping block diagram of FIG. 3, the short-circuit undervoltage relay becomes inoperative, and the output of the OR logic 11 of each phase output becomes O level, so the output of the NOT logic 12 becomes a level.

ヌ、この時、短絡相当の大電流がＦ点に流入した場合、
Ａ、Ｂ電気所ＯＣＴ誤差の影響が顕著となり、Ａ、Ｂ電
気所に設けられた高感度な地絡電流差動リレーにＣＴ誤
差分の電流が差電流となって流れ、その差電流が動作感
度以上となると地絡電流差動リレーが誤動作となる。従
って１、：の場合第３図の地絡電流差動リレー５ａが動
作及び地絡過電圧リレー７が動作となり４かつＮＯＴ論
理１２の出力がルベルであるなめ、＾ＮＤ論理１３の入
力が全てルベル仁なり、引外し指令が出方されてしまう
。以上のように短絡不足電圧リレーが動作できないよう
な遠方事故時には短絡優先かがからす、地絡リレーによ
りミストリップとなる場合があるつ〈発明が解決しよう
とする課題） 前述のように、短絡優先とするための地絡リレーによる
引外しロック条件とし７て短絡不足電圧リレーを用いて
いるが、遠方地絡事故に対して継電器接地点の事故電圧
降下が十分でなく、難路不足電圧リレーが動作できない
ような場合がある。At this time, if a large current equivalent to a short circuit flows into point F,
The influence of the OCT error at electric stations A and B becomes significant, and the current corresponding to the CT error flows as a differential current to the highly sensitive ground fault current differential relay installed at electric stations A and B, and the differential current is activated. If the sensitivity is exceeded, the ground fault current differential relay will malfunction. Therefore, in the case of 1, the ground fault current differential relay 5a in Fig. 3 operates and the ground fault overvoltage relay 7 operates.4 and the output of the NOT logic 12 is a level, so the input of the ^ND logic 13 is all a level. Unfortunately, a trip command was issued. As mentioned above, in the case of a distant accident where the short circuit undervoltage relay cannot operate, the short circuit may be prioritized and the ground fault relay may cause a mistrip. A short-circuit undervoltage relay is used as the tripping lock condition by the ground fault relay to give priority, but the fault voltage drop at the relay grounding point is not sufficient for a distant ground fault, and the short-circuit undervoltage relay is There are cases where it may not work.

従って短絡優先がかからず、多相外部地絡時に短絡電流
相当の大電流にょるＣＴ誤差により差電流が発生した場
合には、高感度な地絡電流差動リレーが誤動作−となり
ミストリップとなる。Therefore, if short circuit priority is not applied and a differential current is generated due to a CT error due to a large current equivalent to a short circuit current during a multi-phase external ground fault, the highly sensitive ground fault current differential relay will malfunction and cause a mistrip. Become.

本発明は、上記問題点を解決するなめになされたもので
あり、遠方事故時に電圧降下が不十分であるために、短
絡不足電圧リレーが動作できない場合であっても、短絡
優先をかけることの可能な電流差動１ｍ電装置を提供す
ることを目的としている。The present invention has been made to solve the above problems, and even if the short circuit undervoltage relay cannot operate due to insufficient voltage drop in the event of a distant accident, it is possible to give short circuit priority. The purpose is to provide a current differential 1m electrical device capable of providing a current differential 1m electrical device.

［発明の構成］ （課題を解決するための手段） 上記目的を達成するため、本発明では対向する各端電気
所の検出電流値の差を求めて動作量とする地絡電流差動
リレーの動作と、地絡過電圧継電器の動作と短絡不足電
圧継電器の不動作を条件に引外し指令を発する電流差動
保護継電装置において、自端の短絡不足電圧継電器と相
手端の短絡不足電圧継電器の各要素のうち、いずれか１
つ以上が２相以上の事故を検出したことを条件に自端の
短絡優先をかけるように構成した。[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention provides a ground fault current differential relay in which the operating amount is obtained by calculating the difference between the detected current values of the opposing terminals. In a current differential protection relay system that issues a trip command under the conditions of operation of a ground fault overvoltage relay and non-operation of a short circuit undervoltage relay, the short circuit undervoltage relay at its own end and the short circuit undervoltage relay at the other end Any one of each element
The configuration is such that priority is given to the short circuit at the own end on the condition that two or more phases have detected a fault.

（作　用） 相手端と自端の不足電圧継電器の動作条件を取込み、両
端の不足電圧継電器の合計で２相以上のヂ故を検出して
短絡と判定し、地絡リレーによるトリ・ソゲをロックす
る。(Function) It takes in the operating conditions of the undervoltage relays at the opposite end and its own end, detects failure of two or more phases in total of the undervoltage relays at both ends, determines it as a short circuit, and prevents the ground fault relay from tripping or disconnecting. lock.

（実施例） 以下、図面を用いて実施例を説明する。(Example) Examples will be described below with reference to the drawings.

第１図ｊａ）は本発明による電流差動継電装置の一実施
例の地絡用外しブロック図例を示したものであり、２１
は相手端の短絡不足電圧＠！電器、１１ａ１１ｂはＯＲ
論理を示す。Fig. 1 ja) shows an example of a ground fault disconnection block diagram of an embodiment of the current differential relay device according to the present invention;
is the short-circuit undervoltage @ of the other end! Electric appliances, 11a11b are OR
Demonstrate logic.

他は第３図で説明したものと同じである。The other parts are the same as those explained in FIG.

今、第２図においてＢ電気所外部Ｆ点に２相地絡事故が
発生し、Ａ電気所の短絡不足電圧リレー６が動作できな
い場合を考える。この時、Ｂ電気所に接地された短絡不
足電圧リレーは事故点に近いので十分動作できる。そこ
で第１図（ａ）に示す如く、相手端の短絡不足電圧リレ
ー２１が動作しな場合、ＯＲ論理ｉｆｂ　、　１１ａは
それぞれルベルとなり、ＮＯＴ論理１２の出力はＱレベ
ルとなるため、ＡＮＤ論理１３の出力はロックされ、地
絡電流差動リレー５ａの不正応動があっても確実に不要
用外しを阻止することができる。このように、相手端の
短絡不足電圧リレーが動作したことにより、自端の短絡
不足電圧リレーか動作できないような事故に対しても、
短絡優先をかけることが可能となる。Now, consider a case where a two-phase ground fault occurs at point F outside electric station B in FIG. 2, and the short-circuit undervoltage relay 6 at electric station A cannot operate. At this time, the short-circuit undervoltage relay grounded at electric station B is close to the fault point and can operate satisfactorily. Therefore, as shown in FIG. 1(a), if the short-circuit undervoltage relay 21 at the other end does not operate, the OR logics ifb and 11a each become a level, and the output of the NOT logic 12 becomes Q level, so the AND logic 13 The output of the ground fault current differential relay 5a is locked, and even if there is an unauthorized response of the ground fault current differential relay 5a, unnecessary removal can be reliably prevented. In this way, even in the event of an accident in which the short-circuit undervoltage relay at the other end cannot operate due to the operation of the short-circuit undervoltage relay at the other end,
It becomes possible to give priority to short circuits.

次に第１図（ｂ）および（Ｃ）に変形例を示す。Next, modified examples are shown in FIGS. 1(b) and 1(C).

第１図（、ｂ　）は第２図に示す知絡不足電圧継電器６
の代わりに１．各相不足電圧継電器を用いた場合の例で
ある。６ａは自端の各相不足電圧継電器、３１は相手端
の各相不足電圧継電器、３２ａ、　３２ｂは自端、相手
端の各相不足電圧継電器かそれぞれ２相以上動作したこ
とを検出する回路を示し、他は第１図（ａ）と同様であ
る。Figure 1 (,b) shows the relay undervoltage relay 6 shown in Figure 2.
Instead of 1. This is an example of using undervoltage relays for each phase. 6a is an undervoltage relay for each phase at the own end, 31 is an undervoltage relay for each phase at the opposite end, and 32a and 32b are circuits for detecting the operation of two or more phases of the undervoltage relays for each phase at the own end and the opposite end, respectively. The other parts are the same as in FIG. 1(a).

ここても第１図（ａ）で説明したものと同様に、自端の
各相不足電圧継電器６ａが動作できなくとも、相手端の
各相不足電圧継電器３１が２相以上動作した場合、ＮＯ
Ｔ論理１２の出力を０レベルとし、へＮＯ論理の出力を
ロックすることができる。Here, similarly to what was explained in FIG. 1(a), even if the phase undervoltage relay 6a at the own end cannot operate, if the phase undervoltage relay 31 at the other end operates for two or more phases, NO
The output of the T logic 12 can be set to 0 level, and the output of the NO logic can be locked.

ス、第１図（ｃ）は（ｂ）と同様に各相不足電圧継電器
を用いた例であり、３３は自端の各相不足電圧継電器６
ａと相手端の各相不足電圧継電器３１を合わせて６相の
うち、異相による２相以上の動作を検出する回路で°あ
り、本回路による出力がルベルとなった場合、前述の実
施例と同様の効果を得ることかできる。Figure 1(c) is an example in which undervoltage relays for each phase are used similarly to (b), and 33 is an undervoltage relay for each phase at its own end 6.
This is a circuit that detects the operation of two or more phases due to different phases out of a total of six phases, including the undervoltage relay 31 of each phase at the opposite end. You can achieve a similar effect.

ところで、第１図（ａ）に示すＯＲ論理１１ｂ、および
第１図（ｂ）に示す相手端の各相不足電圧継電器３１の
２相以上の動作を検出する回路３２１）は、自端スは相
手端のどちらに設けてもがまわない。By the way, the OR logic 11b shown in FIG. 1(a) and the circuit 321) for detecting the operation of two or more phases of each phase undervoltage relay 31 at the other end shown in FIG. It does not matter which end of the other end it is installed.

［発明の効果］ 以上説明しな如く、本発明によれば相手端の不足電圧継
電器の動作柴件を受信し７、目端の不足電圧リレーと相
手端の不足電圧リレーの応動を総合して判定することに
より、自端の不足電圧継電器の動作か期待できないよう
な２相以上の事故のときでも、確実に短絡優先とするこ
とができる抵抗接地光用電流差動保護継電装置を提供で
きる。[Effects of the Invention] As described above, according to the present invention, the operating conditions of the undervoltage relay at the opposite end are received, and the responses of the undervoltage relay at the end and the undervoltage relay at the opposite end are integrated. By making this determination, it is possible to provide a resistance-grounded optical current differential protection relay device that can reliably give priority to short circuits even in the event of an accident involving two or more phases in which the undervoltage relay at its own end cannot be expected to operate. .

なお、以上の説明は２端系統を例に説明したが、多端子
系統にも適用可能なことは言うまでもない。Note that although the above explanation has been given using a two-terminal system as an example, it goes without saying that it is also applicable to a multi-terminal system.

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

第１゛図（ａＨｂＨｃ）は本発明による電流差動保護継
電装置の一実施例地絡用件しブロック図、第２図は系統
図、第３図は従来の電流差動保護継電装置の地絡例外し
ブロック図である。 ５ａ・・・地絡電流差動継電器 ６・・・短絡不足電圧継電器 ７・・・地絡過電圧継電器Fig. 1 (aHbHc) is a block diagram showing ground fault requirements of one embodiment of the current differential protection relay according to the present invention, Fig. 2 is a system diagram, and Fig. 3 is a conventional current differential protection relay. FIG. 2 is a block diagram of a ground fault exception. 5a...Ground fault current differential relay 6...Short circuit undervoltage relay 7...Ground fault overvoltage relay

Claims (1)

【特許請求の範囲】[Claims] 　対向する各端電気所の検出電流値の差を求めて動作量
とする地絡電流差動継電器の動作と、地絡過電圧継電器
の動作と、短絡不足電圧継電器の不動作を条件に引外し
指令を発する電流差動保護継電装置において、自端の短
絡不足電圧継電器と相手端の短絡不足電圧継電器の各要
素のうち、いずれか１つ以上が２相以上の事故を検出し
たことを条件に、自端の短絡優先をかけるようにしたこ
とを特徴とする電流差動保護継電装置。A trip command is issued based on the operation of the ground fault current differential relay, the operation of the ground fault overvoltage relay, and the non-operation of the short circuit undervoltage relay, which is determined by calculating the difference between the detected current values at the opposite ends of the electrical station. In a current differential protection relay device that generates a current, the condition is that one or more of the short-circuit undervoltage relays at its own end and the short-circuit undervoltage relay at the opposite end detects a two-phase or more fault. , a current differential protection relay device characterized in that short-circuit priority is given to the own end.