JPH0452694B2 - - Google Patents
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- Publication number
- JPH0452694B2 JPH0452694B2 JP58138075A JP13807583A JPH0452694B2 JP H0452694 B2 JPH0452694 B2 JP H0452694B2 JP 58138075 A JP58138075 A JP 58138075A JP 13807583 A JP13807583 A JP 13807583A JP H0452694 B2 JPH0452694 B2 JP H0452694B2
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- Prior art keywords
- digital
- data
- digital data
- current
- analog
- 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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- 230000005540 biological transmission Effects 0.000 claims description 32
- 238000006243 chemical reaction Methods 0.000 claims description 15
- 238000000034 method Methods 0.000 claims description 8
- 230000001681 protective effect Effects 0.000 claims 3
- 238000010586 diagram Methods 0.000 description 9
- 229920006395 saturated elastomer Polymers 0.000 description 4
- 238000005070 sampling Methods 0.000 description 3
- 238000001514 detection method Methods 0.000 description 2
- 230000007257 malfunction Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 1
- 239000000284 extract Substances 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 239000013307 optical fiber Substances 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
Landscapes
- Arrangements For Transmission Of Measured Signals (AREA)
- Emergency Protection Circuit Devices (AREA)
Description
【発明の詳細な説明】
本発明はデイジタルデータ伝送による差動保護
継電器に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a differential protection relay with digital data transmission.
送電線の差動保護継電器は、一般には第１図に
示すように、電気所１と２を結ぶ送電線３の両端
に変流器４，５を設けて両電気所１，２での送電
線電流I1，I2を検出し、この検出電流をパイロツ
トワイヤー６等で相互に相手電気所の差動保護リ
レー７，８に伝送し、各リレー７，８で自電気所
と相手電気所の送電線差電流を求めて送電線３に
事故発生があるか否かを判定するようにしてい
る。 As shown in Figure 1, differential protection relays for power transmission lines generally have current transformers 4 and 5 installed at both ends of a power transmission line 3 that connects electrical stations 1 and 2, so that the transmission between both electrical stations 1 and 2 is protected. The wire currents I 1 and I 2 are detected, and the detected currents are mutually transmitted to the differential protection relays 7 and 8 of the other electric station using the pilot wire 6, etc., and each relay 7 and 8 connects the own electric station and the other electric station. It is determined whether or not an accident has occurred in the power transmission line 3 by determining the power transmission line difference current.
デイジタル方式の差動保護継電器は、第２図に
示すように変流器４，５からアナログ信号を夫々
アナログ−デイジタル変換器９，１０によつてデ
イジタル信号に変換し、デイジタルデータ伝送路
１１を通して相互に相手端に伝送し、夫々のデイ
ジタル式差動保護リレー１２，１３におけるデイ
ジタル的処理によつて保護出力を得る。 As shown in FIG. 2, the digital differential protection relay converts analog signals from current transformers 4 and 5 into digital signals by analog-to-digital converters 9 and 10, respectively, and transmits them through a digital data transmission line 11. The signals are mutually transmitted to the other end, and protection outputs are obtained through digital processing in the respective digital differential protection relays 12 and 13.
このデイジタルデ式差動保護継電器はデイジタ
ル伝送になつてアナログ式のものに比べて信頼性
が高く長距離のデータ伝送も可能にするが、伝送
路１１は強電ケーブルと並設されることが多く、
電力系統の開閉サージ、雷サージ、事故電流など
の影響を受けることがる。この影響を軽減させる
方法としては、伝送路そのものを電器的ノイズに
強い光フアイバーによる光伝送とする方法、デー
タの伝送スピードを遅くする方法、伝送信号レベ
ルを高くする方法などがある。 This digital type differential protection relay uses digital transmission, which is more reliable than analog type, and enables long-distance data transmission, but the transmission line 11 is often installed in parallel with a high-power cable.
It can be affected by power system switching surges, lightning surges, fault currents, etc. Methods for reducing this effect include using optical fiber as the transmission path itself, which is resistant to electrical noise, slowing down the data transmission speed, and increasing the transmission signal level.
しかし、光伝送方法は少ないデータ伝送には割
高になるし既設のツイストペアケーブルを利用で
きないなどの理由から適用しにくい。また、信号
レベルを高くする方法は信号対ノイズ比（Ｓ／
Ｎ）を改善するのに極めて有効であるが、同じケ
ーブル内に他の制御信号や電話信号がある場合に
漏話（クロストーク）の影響が大きくなる問題が
ある。 However, optical transmission methods are difficult to apply for small data transmission because they are expensive and cannot use existing twisted pair cables. Also, the method to increase the signal level is to increase the signal-to-noise ratio (S/
Although this method is extremely effective in improving N), there is a problem in that the influence of crosstalk becomes large when there are other control signals or telephone signals in the same cable.
伝送スピードを下げる方法は、上述のような問
題がなく信頼度向上に効果的であるが、伝送する
データ数と１つのデータビツト数とサンプリング
周波数をどの程度にするかによつて一定の制約が
ある。このうち、伝送するデータ数は電流データ
であれば一般に３相分と零相分の４つのデータに
なり、各データは基本周波数の６〜12倍程度のサ
ンプリング周波数を必要としてこれらをデータ伝
送スピードを下げるためのパラメータすることは
できず、結果的にデータのビツト数を下げること
が伝送スピードを下げるための方法となる。しか
し、データのビツト数低減には保護性能を低下さ
せるという新たな問題を起す。 The method of lowering the transmission speed is effective in improving reliability without the problems mentioned above, but there are certain restrictions depending on the amount of data to be transmitted, the number of data bits per data bit, and the sampling frequency. be. Of these, the number of data to be transmitted is generally 4 data for 3 phases and 0 phase for current data, and each data requires a sampling frequency of about 6 to 12 times the fundamental frequency to reduce the data transmission speed. It is not possible to set a parameter to lower the transmission speed, and as a result, the method of lowering the transmission speed is to lower the number of data bits. However, reducing the number of data bits causes a new problem of lowering protection performance.
本発明の目的はデータのビツト数低減により伝
送スピードを下げる方法にしてしかも保護性能を
低下させることのない差動保護継電器を得るにあ
る。 SUMMARY OF THE INVENTION An object of the present invention is to provide a differential protection relay that uses a method of reducing transmission speed by reducing the number of data bits and does not reduce protection performance.
本発明は、変流器から得る電流検出信号をアナ
ログデイジタル変換するのに入力に比例するビツ
ト数を持たせない変換器を設け、一定レベル以上
の入力には最大値のデイジタル量に制限した少な
いビツト数で互いに相手電気所に伝送し、夫々の
電気所ではデイジタルフイルタを設けてデイジタ
ルデータから高調波を除去した基本波のデイジタ
ルデータを復元し、このデータを使つて差動保護
リレーによる保護演算をすることを特徴とする。 The present invention provides a converter that does not have the number of bits proportional to the input to convert a current detection signal obtained from a current transformer into an analog-to-digital signal, and for inputs above a certain level, a small number of bits that is limited to the maximum digital value is provided. The data is transmitted to the other power station in the number of bits, and each power station installs a digital filter to remove harmonics from the digital data to restore the fundamental wave digital data.This data is used to perform protection calculations using differential protection relays. It is characterized by
第３図は本発明の一実施例を示すブロツク図で
ある。同図は第２図中の電気所２における差動保
護リレー１３のデータ入力系統を示し、自電気所
での送電線３の電流を変流器５で検出し、この検
出電流をアナログ−デイジタル変換器１０でデイ
ジタルデータ列に変換する。一方、相手電気所か
らは送電線３の電流を変流器４で検出し、この検
出電流をアナログ−デイジタル変換器９でデイジ
タルデータ列に変換して伝送路１１を介して自電
気所に伝送されてくる。これらアナログ−デイジ
タル変換器９，１０は従来と同等の分解能を持た
せながら変換ビツト数を少なくし、一定レベル以
上の入力には最大値のデイジタル量に制限した変
換をするよう構成している。変換器９，１０から
得るデイジタルデータはデイジタルフイルタ１４
によつて夫々高調波を除去した基本波のデイジタ
ルデータ列として取出し、差動保護リレー１３へ
の保護演算入力にする。トリツプリレー１５は、
リレー１３からのトリツプ信号によつてしや断器
の引外し出力を得る。 FIG. 3 is a block diagram showing one embodiment of the present invention. This figure shows the data input system of the differential protection relay 13 in the electric station 2 in Fig. 2. The current in the transmission line 3 at the own electric station is detected by the current transformer 5, and this detected current is converted into an analog-digital A converter 10 converts the data into a digital data string. On the other hand, from the other power station, the current in the power transmission line 3 is detected by a current transformer 4, and this detected current is converted into a digital data string by an analog-digital converter 9 and transmitted to the own power station via a transmission line 11. It will be done. These analog-to-digital converters 9 and 10 are configured to reduce the number of conversion bits while maintaining the same resolution as the conventional converters, and to perform conversion limited to the maximum digital amount for inputs above a certain level. The digital data obtained from the converters 9 and 10 is passed through a digital filter 14.
The digital data string of the fundamental wave from which each harmonic has been removed is taken out as a digital data string, and is used as a protection calculation input to the differential protection relay 13. Tritu Relay 15 is
A trip signal from the relay 13 provides a tripping output for the breaker.
アナログ−デイジタル変換器１０の出力は相手
電気所１側にも伝送され、該電気所においてもデ
イジタルフイルタ１４と同様のフイルタを設けて
保護リレーの入力に高調波除去を施すよう構成し
ている。 The output of the analog-digital converter 10 is also transmitted to the other electric station 1, and the electric station is also provided with a filter similar to the digital filter 14 to remove harmonics from the input of the protection relay.
こうした構成において、アナログ−デイジタル
変換器９，１０は前述のように変換ビツト数を従
来のものより少なくしている。検出電流Ｉの最大
振幅（Ｏ−Ｐ）値が第４図に示すようにIMAXとな
る場合、この検出電流Ｉに対するアナログ−デイ
ジタル変換には従来から12ビツトのデイジタルデ
ータとして取扱い、そのうち最上位ビツト桁の12
ビツト目はデータの正、負極性を示すサインビツ
トとし、データの分解能は２11（2048）分の１と
している。従つて、最下位ビツトを１アンペアの
重みとすれば最大振幅値IMAXは2048アンペアまで
入力に比例したデイジタルデータとして得るし、
最下位ビツトが50アンペアの重みなら最大100キ
ロアンペアまでのデータを得る。 In such a configuration, the analog-to-digital converters 9 and 10 have a smaller number of conversion bits than the conventional ones, as described above. When the maximum amplitude (O-P) value of the detected current I is I MAX as shown in Figure 4, analog-to-digital conversion for this detected current I is conventionally treated as 12-bit digital data, of which the highest 12 bit digits
The th bit is a sign bit indicating the positive or negative polarity of the data, and the resolution of the data is 1/2 11 (2048). Therefore, if the least significant bit is weighted by 1 ampere, the maximum amplitude value I MAX can be obtained as digital data proportional to the input up to 2048 amperes,
If the least significant bit has a weight of 50 amps, you will get data up to 100 kiloamps.
この変換器を用いる場合、データの伝送スピー
ドはデータ数とサンプリング周波数と変換ビツト
数の積として表わすことができるので、ビツト数
を少なくすることは直ちに伝送スピードの低下の
実現になる。従来の12ビツトのデータ伝送であれ
ば、最小限必要な電流から短絡などによつて流れ
る最大の電流までを表現することができるため、
第５図に示すように検出電流I1とI2に対して斜線
で示す差動動作領域を得ることができる。 When using this converter, the data transmission speed can be expressed as the product of the number of data, the sampling frequency, and the number of conversion bits, so reducing the number of bits immediately results in a reduction in the transmission speed. With conventional 12-bit data transmission, it is possible to express everything from the minimum required current to the maximum current flowing due to short circuits, etc.
As shown in FIG. 5, a differential operation region indicated by diagonal lines can be obtained for the detection currents I 1 and I 2 .
一方、本実施例ではアナログ−デイジタル変換
器９，１０の変換ビツト数を12ビツトから８ビツ
ト程度に少なくする。この場合、第６図に示すよ
うに電流IL以上の検出値には該電流ILに相当する
７ビツトの最大値データになり、データの分解能
は27（128）分の１になつて従来の２11分の１に比
べて1/16になる。従つて、最下位ビツトを同じ50
アンペアの重みとすれば変換制限電流ILは6.5キ
ロアンペアとなる。この変換制限電流以上の入力
では変換器９，１０は飽和状態となつて変換した
デイジタルデータは一定値となる。 On the other hand, in this embodiment, the number of conversion bits of the analog-digital converters 9 and 10 is reduced from 12 bits to about 8 bits. In this case, as shown in Figure 6, the detected value of the current I L or more will be the maximum value data of 7 bits corresponding to the current I L , and the data resolution will be 1/27 (128). It is 1/16 compared to the conventional 1/211 . Therefore, the least significant bit is the same 50
If weighted in amperes, the conversion limit current I L will be 6.5 kiloamperes. When the input exceeds the conversion limit current, the converters 9 and 10 become saturated and the converted digital data becomes a constant value.
従つて、変換器９，１０のデイジタルデータ列
は電流ILを越える入力に対して該電流ILをリミツ
ト値とする矩形波の変換データとなる。 Therefore, the digital data strings of the converters 9 and 10 become rectangular wave conversion data with the current I L as the limit value for inputs exceeding the current I L .
このように変換されたデータは伝送スピードを
下げることになるが、制限電流IL以上の電流デー
タは伝送されない。そこで、本実施例では、デイ
ジタルデータ列をデイジタルフイルタ１４に取込
んで基本波成分のみのデータ列として再成する。
矩形波の周波数スペクトルは基本波と奇数次高調
波及び直流分より成り立つているため、デイジタ
ルフイルタ１４においてはデイジタルデータ列か
ら直流分と高調波分を除去したデータ列として取
出す。但し、アナログ−デイジタル変換前の入力
に対しては比例するものでなく、入力が一定値以
上になると次第に飽和する波形のデータ列とな
り、入力がさらに大きくなると殆ど一定の出力に
なる。 Data converted in this way will reduce the transmission speed, but current data exceeding the limit current I L will not be transmitted. Therefore, in this embodiment, the digital data string is taken into the digital filter 14 and regenerated as a data string containing only the fundamental wave component.
Since the frequency spectrum of a rectangular wave consists of a fundamental wave, odd-numbered harmonics, and a DC component, the digital filter 14 extracts the DC component and harmonics from the digital data string as a data string. However, it is not proportional to the input before analog-to-digital conversion, and when the input exceeds a certain value, it becomes a data string with a waveform that gradually becomes saturated, and when the input becomes even larger, the output becomes almost constant.
このデイジタルフイルタ１４を通したデータ列
は差動保護リレー１３による保護演算に供され
る。このリレー１３の動作特性は検出電流の変換
データが飽和状態となつて伝送されるため第７図
に示すように電流IS以上では飽和特性になるが、
第１図や第２図に示す２端子の送電線では流出電
流が少ないため何ら問題は生じない。 The data string passed through this digital filter 14 is subjected to protection calculation by a differential protection relay 13. The operating characteristic of this relay 13 is that the converted data of the detected current is transmitted in a saturated state, so as shown in FIG. 7, it becomes saturated when the current exceeds I S.
In the two-terminal power transmission line shown in FIGS. 1 and 2, no problem occurs because the outflow current is small.
以上のとおり、本発明によれば、アナログ−デ
イジタル変換のビツト数を減らしてデータ伝送ス
ピードを下げることによりデータの伝送品質を向
上させ、デイジタルフイルタによつて基本波成分
を取出すデイジタル処理手段を設けることにより
誤動作や誤不動作の少ない信頼性の高い継電器を
実現できる。 As described above, according to the present invention, data transmission quality is improved by reducing the number of analog-to-digital conversion bits and data transmission speed, and digital processing means is provided for extracting the fundamental wave component using a digital filter. As a result, a highly reliable relay with fewer malfunctions and malfunctions can be realized.
第１図は従来のパイロツトワイヤー式差動保護
継電器を示す図、第２図は従来のデイジタル式継
電器を示す図、第３図は本発明の一実施例を示す
要部構成図、第４図は従来のアナログ−デイジタ
ル変換を説明するための波形図、第５図は従来の
継電器の動作特性図、第６図は本発明におけるア
ナログ−デイジタル変換を説明するための波形
図、第７図は本発明の継電器の動作特性図であ
る。
１，２……電気所、３……送電線、９，１０…
…アナログ−デイジタル変換器、１１……伝送
路、１２，１３……差動保護リレー、１４……デ
イジタルフイルタ。
Fig. 1 is a diagram showing a conventional pilot wire type differential protection relay, Fig. 2 is a diagram showing a conventional digital relay, Fig. 3 is a main part configuration diagram showing an embodiment of the present invention, and Fig. 4 5 is a waveform diagram for explaining the conventional analog-to-digital conversion, FIG. 5 is an operating characteristic diagram of a conventional relay, FIG. 6 is a waveform diagram for explaining the analog-to-digital conversion in the present invention, and FIG. 7 is a waveform diagram for explaining the analog-to-digital conversion in the present invention. FIG. 3 is an operational characteristic diagram of the relay of the present invention. 1, 2...Electric station, 3...Power line, 9,10...
...Analog-digital converter, 11...Transmission line, 12, 13...Differential protection relay, 14...Digital filter.
Claims (1)
夫々アナログ−デイジタル変換して相手電気所に
デイジタルデータとして伝送し、両電気所で夫々
相手電気所との差電流を該デイジタルデータを使
つた演算により保護出力を得るデイジタル式差動
保護継電器において、電気所における検出電流の
アナログ−デイジタル変換には一定レベル以上の
入力には最大値のデイジタル量に制限してデイジ
タルデータ列として相手電気所に伝送し、このデ
イジタルデータ列からデイジタルフイルタによつ
て検出電流の基本波成分に相当するデイジタルデ
ータ列によつてデイジタル処理し、保護出力を得
る構成にしたことを特徴とするデイジタル式差動
保護継電器。1. Detect the power transmission line currents at opposing electric stations, convert them into analog-to-digital data, and transmit them to the other electric station as digital data. Both electric stations use the digital data to calculate the difference in current from the other electric station. In a digital differential protective relay that obtains a protective output through calculation, the analog-to-digital conversion of the detected current at the electric station is limited to the maximum digital amount for inputs above a certain level, and the output is sent as a digital data string to the other electric station. A digital differential protection relay, characterized in that it is configured to transmit the digital data and digitally process the digital data string using a digital filter using a digital data string corresponding to the fundamental wave component of the detected current to obtain a protective output. .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58138075A JPS6028718A (en) | 1983-07-28 | 1983-07-28 | Digital difference protecting relay |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP58138075A JPS6028718A (en) | 1983-07-28 | 1983-07-28 | Digital difference protecting relay |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6028718A JPS6028718A (en) | 1985-02-13 |
| JPH0452694B2 true JPH0452694B2 (en) | 1992-08-24 |
Family
ID=15213375
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP58138075A Granted JPS6028718A (en) | 1983-07-28 | 1983-07-28 | Digital difference protecting relay |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6028718A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0234452A (en) * | 1988-07-26 | 1990-02-05 | Mitsubishi Motors Corp | Emergency escape device for automobile |
| JP4769480B2 (en) * | 2004-04-27 | 2011-09-07 | パナソニック株式会社 | Optical head, optical information recording / reproducing device, computer, video reproducing device, server, car navigation system |
| JP2010008743A (en) * | 2008-06-27 | 2010-01-14 | Hoya Corp | Lens holding structure |
-
1983
- 1983-07-28 JP JP58138075A patent/JPS6028718A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6028718A (en) | 1985-02-13 |
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