JPH0919050A - Overcurrent relay - Google Patents
Overcurrent relayInfo
- Publication number
- JPH0919050A JPH0919050A JP7183516A JP18351695A JPH0919050A JP H0919050 A JPH0919050 A JP H0919050A JP 7183516 A JP7183516 A JP 7183516A JP 18351695 A JP18351695 A JP 18351695A JP H0919050 A JPH0919050 A JP H0919050A
- Authority
- JP
- Japan
- Prior art keywords
- overload
- allowable
- temperature
- overcurrent relay
- allowable time
- 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.)
- Pending
Links
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- Emergency Protection Circuit Devices (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、過負荷保護に用いられ
る反限時過電流継電器に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anti-time limit overcurrent relay used for overload protection.
【０００２】[0002]
【従来の技術】電力線あるは電力機器の過負荷を保護す
るものとして過負荷保護継電器がある。電力系統保護用
として代表的なものに送電線過負荷保護継電器，変圧器
過負荷保護継電器がある。この種の過負荷継電器は図４
に示すように、保護対象となる電力線や電力機器の過負
荷特性曲線（以下、過負荷曲線と呼ぶ）に対して、整定
値の異なる複数の過電流継電器を段階的に適用し保護す
る形態が一般的であった。2. Description of the Related Art There is an overload protection relay for protecting an overload of a power line or power equipment. Typical examples for power system protection are transmission line overload protection relays and transformer overload protection relays. This type of overload relay is shown in Fig. 4.
As shown in, there is a mode in which a plurality of overcurrent relays with different set values are applied in stages to protect the overload characteristic curve (hereinafter referred to as an overload curve) of the power line or power equipment to be protected. It was common.
【０００３】この場合、各過電流継電器と整定の異なる
複数の限時タイマーを組み合わせることで、運転状態が
過負荷曲線の危険状態に至らないうちに負荷をしゃ断す
る保護方式が採られていた。しかしながら、この種の従
来方式では過電流継電器の動作限界付近での過負荷をし
ゃ断できない可能性があるため（整定時間を動作限界近
くに設定すると誤動作するため）、負荷変動を考慮して
過電流継電器の整定を過負荷曲線より十分安全側の領域
で行なう必要がある。In this case, a protection system has been adopted in which each overcurrent relay is combined with a plurality of time limit timers having different settings to cut off the load before the operating condition reaches the dangerous condition of the overload curve. However, with this type of conventional method, there is a possibility that the overload near the operating limit of the overcurrent relay cannot be cut off (because malfunction occurs if the settling time is set near the operating limit). It is necessary to set the relay in a region that is sufficiently safe from the overload curve.
【０００４】そのため、時間的に余裕がある過負荷に対
しても短時間でしゃ断せざるを得ない場合があり、許容
範囲内、即ち、危険領域に至らない範囲での過負荷運転
を十分に行なうことができないという問題点があった。Therefore, it may be necessary to cut off in a short time even for an overload that has a time margin, and the overload operation is sufficiently performed within an allowable range, that is, a range that does not reach the dangerous area. There was a problem that it could not be done.
【０００５】このような問題点を解決するために、過負
荷時の負荷しゃ断を過負荷特性に応じた方式で行ない、
電力供給のサービス向上を図ることを狙いとした反限時
過電流継電器が特開昭６２−１７８１１６号で既に提案
されている。この提案では、保護対象電力線あるいは電
力機器の熱的挙動を継電器内で正確にシミュレートする
ことで、適正な継電器特性を実現する手段を示してい
る。In order to solve such a problem, the load is cut off at the time of overload by a method according to the overload characteristic,
An anti-time limit overcurrent relay aiming at improving the service of electric power supply has already been proposed in Japanese Patent Laid-Open No. 62-178116. In this proposal, a means for realizing proper relay characteristics by accurately simulating the thermal behavior of the protected power line or power equipment in the relay is shown.
【０００６】具体的には、所定の温度上昇式により、継
電器に取り込まれる負荷電流の値から温度上昇を求め、
これが所定温度、例えば保護対象の許容限界温度に到達
することで、負荷しゃ断出力を生ずるものである。一般
的に、前記過負荷曲線は前記温度上昇式において、一定
の過負荷電流が継続して通電されることを仮定して得ら
れるものである。Specifically, the temperature rise is obtained from the value of the load current taken into the relay by a predetermined temperature rise formula,
When this reaches a predetermined temperature, for example, the allowable limit temperature of the object to be protected, a load cutoff output is generated. Generally, the overload curve is obtained on the assumption that a constant overload current is continuously applied in the temperature rising equation.
【０００７】したがって熱的挙動を継電器内で正確にシ
ミュレートすることを考慮した前記既提案の継電器の定
格電流特性は図５に示す形態となり、過負荷曲線と合致
したものとなる。即ち、危険領域に至らない領域での運
転が十分に行なえ、かつ負荷が頻繁に変動するような系
統においても、常に保護対象の能力を最大限に活用した
過負荷運転が可能となる。Therefore, the rated current characteristic of the above-mentioned proposed relay in consideration of accurately simulating the thermal behavior in the relay has the form shown in FIG. 5, which matches the overload curve. That is, even in a system in which the operation can be sufficiently performed in the area that does not reach the dangerous area and the load changes frequently, it is possible to always perform the overload operation that maximizes the capacity of the protection target.
【０００８】一般に、電力線あるいは電力機器の温度上
昇式は、以下の(1) 式に示す微分方程式で与えられる。
これを継電器内で演算する手段については前記既提案に
述べられているように以下(2) 式の演算を行なえばよ
い。Generally, the temperature rise formula of the power line or the power equipment is given by the differential equation shown in the following formula (1).
As for the means for calculating this in the relay, the calculation of the following equation (2) may be performed as described in the above-mentioned proposal.
【数１】 このような演算は、電力系統のための保護，制御装置に
マイクロコンピュータを適用した保護継電器（以下、デ
ィジタルリレーと呼ぶ）により実現できる。[Equation 1] Such calculation can be realized by a protection relay (hereinafter, referred to as a digital relay) in which a microcomputer is applied to a protection and control device for the power system.
【０００９】[0009]
【発明が解決しようとする課題】上記従来方式によれ
ば、過負荷時に負荷特性に応じた負荷しゃ断を行なうこ
とで、常に保護対象の能力を最大限に活用した負荷運転
が可能になるが、この負荷しゃ断は予め過負荷時にしゃ
断する順次を決めておき、その設定した順に行なってい
く。According to the above-mentioned conventional method, by performing load cutoff according to the load characteristic at the time of overload, it is possible to always perform load operation by making maximum use of the capacity of the protection target. This load cutoff is determined in advance in the order of cutoff at the time of overload, and is performed in the set order.
【００１０】図６は変圧器の過負荷保護を示す図で、変
圧器の負荷状態を過負荷リレーで検出し、その程度に応
じて負荷をしゃ断するものである。例えば図６の場合、
過負荷時に予め設定した第１グループをしゃ断し、その
結果として過負荷が解消しなければ続けて第２グルー
プ，第３グループの順でしゃ断が行なわれる。FIG. 6 is a diagram showing overload protection of a transformer, in which the load state of the transformer is detected by an overload relay and the load is cut off according to the degree. For example, in the case of FIG.
When the overload is overloaded, the preset first group is cut off. As a result, if the overload is not resolved, the second group and the third group are cut off successively.
【００１１】しかし、系統の運転状態は多様であり、必
ずしも図６のように当初設定した順序で負荷しゃ断を行
なえない場合がある。又、系統操作で過負荷を解消した
時に再び過負荷とならないことを確認する手段が従来技
術では実現できない。However, there are various operating states of the system, and there are cases where load interruption cannot always be performed in the initially set order as shown in FIG. Further, the conventional technique cannot realize means for confirming that the overload will not be over again when the overload is eliminated by operating the system.
【００１２】本発明は上記課題を解決するためになされ
たものであり、負荷しゃ断に至る前に系統操作により過
負荷をしゃ断し、その結果として最終的に過負荷を解消
したかを判断できる過電流継電器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-mentioned problems, and it is possible to judge whether or not the overload is finally eliminated by cutting off the overload by operating the system before the load is cut off. The purpose is to provide a current relay.
【００１３】[0013]
【課題を解決するための手段】本発明の請求項１に係る
過電流継電器は、過負荷保護に用いられる反限時特性を
有する過電流継電器において、保護対象である電力線又
は電力機器等の熱的挙動を演算する温度上昇演算手段
と、前記温度上昇演算手段により得られた温度と保護対
象機器に応じた過負荷許容限界温度との大小関係を比較
してしゃ断指令を出力する出力判定手段と、前記算出温
度と過負荷許容限界温度とにより、許容限界温度に到達
するまでの許容時間を算出する許容時間算出手段と、前
記許容時間算出手段にて算出した許容時間を総合制御所
又は給電指令所へ伝送する伝送手段とを備えた。SUMMARY OF THE INVENTION An overcurrent relay according to claim 1 of the present invention is an overcurrent relay having anti-time characteristic used for overload protection, in which a thermal protection of a power line or a power equipment to be protected is performed. A temperature rise calculating means for calculating the behavior, an output determining means for comparing the temperature obtained by the temperature rise calculating means with an overload allowable limit temperature according to the protection target device and outputting a cutoff command, An allowable time calculating means for calculating an allowable time until the allowable limit temperature is reached based on the calculated temperature and the overload allowable limit temperature, and an allowable time calculated by the allowable time calculating means is set as an overall control station or a power supply command station. And a transmission means for transmitting to.
【００１４】[0014]
【作用】本発明の過電流継電器は、保護対象機器毎の熱
的挙動による温度上昇値を求めて夫々の過負荷許容限界
温度と比較し、その結果許容限界温度に到達するまでの
許容時間を対象機器毎に求めている。ここで求めた各許
容時間は総合制御所又は給電指令所へ伝送する。これを
受けた電気所は伝送された許容時間により負荷しゃ断に
至る前に系統の運転状態に応じた系統操作で過負荷をし
ゃ断することができ、その結果として最終的に過負荷を
解消したかを判断する。In the overcurrent relay of the present invention, the temperature rise value due to the thermal behavior of each device to be protected is calculated and compared with the respective overload allowable limit temperatures, and as a result, the allowable time until the allowable limit temperature is reached is determined. Required for each target device. Each allowable time obtained here is transmitted to the general control station or the power supply command station. The electric power station receiving this can cut off the overload by operating the system according to the operating state of the system before the load is cut off due to the allowed time transmitted, and as a result, has the overload finally been resolved? To judge.
【００１５】[0015]
【実施例】以下図面を参照して実施例を説明する。図１
は本発明の過電流継電器の実施例の構成図である。図１
は保護対象に流れている電流を入力として温度上昇演算
により保護対象を保護するための出力を発生する過電流
継電器である。図１において、１は保護対象、２は過電
流継電器、３は伝送手段であり、過電流継電器２は電流
データ取得手段21と温度上昇演算手段22と出力判定手段
23と許容時間算出手段24からなる。An embodiment will be described below with reference to the drawings. FIG.
FIG. 3 is a configuration diagram of an embodiment of an overcurrent relay of the present invention. FIG.
Is an overcurrent relay that receives an electric current flowing through a protection target and generates an output for protecting the protection target by calculating a temperature rise. In FIG. 1, 1 is a protection target, 2 is an overcurrent relay, 3 is a transmission means, and the overcurrent relay 2 is a current data acquisition means 21, a temperature rise calculation means 22, and an output determination means.
23 and an allowable time calculating means 24.
【００１６】まず保護対象よりの電流Ｉをデータ取得手
段21で取得しディジタル変換後、実効値を算出する。本
手段はディジタルリレーの一般的手法、即ち、アナログ
・ディジタル変換器によりディジタルデータの取得及び
整流加算，２値加算などによる瞬時値から実効値への変
換で実現される。ここで得られた電流データを温度上昇
演算手段22に導入し、(2) 式を用いて温度上昇演算を行
ない、保護対象の温度を求める。First, the current I from the object to be protected is acquired by the data acquisition means 21, digitally converted, and the effective value is calculated. This means is realized by a general method of a digital relay, that is, by acquiring digital data by an analog-digital converter and converting an instantaneous value into an effective value by rectification addition, binary addition, and the like. The current data obtained here is introduced into the temperature rise calculation means 22, and the temperature rise calculation is performed using the equation (2) to obtain the temperature of the protection target.
【００１７】出力判定手段23では温度上昇演算手段22に
て得られた温度が許容限界温度を超えた場合に出力す
る。許容時間算出手段24では温度上昇演算手段22にて得
られた温度と許容限界温度とにより負荷しゃ断に至るま
での許容時間を算出する。以下に許容時間算出式を示
す。(1) 式は(3) 式の如く変形することができる。又、
(3) 式を温度上昇θに関して積分すると(4) 式を得る。The output determination means 23 outputs when the temperature obtained by the temperature rise calculation means 22 exceeds the allowable limit temperature. The allowable time calculating means 24 calculates the allowable time until the load is cut off based on the temperature obtained by the temperature increase calculating means 22 and the allowable limit temperature. The allowable time calculation formula is shown below. Equation (1) can be transformed into equation (3). or,
Integrating equation (3) with respect to the temperature rise θ yields equation (4).
【００１８】[0018]
【数２】 [Equation 2]
【００１９】許容時間算出手段24にて(4) 式の許容時間
ｔを求め、得られた許容時間は変電所等の本継電器を設
置している電気所から伝送手段３にて系統の切替え操作
を行なう総合制御所，給電指令所等を伝送する。The permissible time t of the equation (4) is calculated by the permissible time calculating means 24, and the obtained permissible time is switched from the electric station such as a substation where the main relay is installed to the transmission means 3 to switch the system. It transmits to the general control station, power supply command center, etc.
【００２０】以上述べたように、伝送されてきた許容時
間をもとに系統操作にて負荷の切替えが可能であり、負
荷しゃ断に至る前に人間系の系統操作で過負荷をしゃ断
することができ、その結果として最終的に過負荷を解消
したかを判断することができる。As described above, it is possible to switch the load by system operation based on the permissible time transmitted, and it is possible to cut off the overload by human system operation before the load is cut off. As a result, it is possible to finally determine whether or not the overload is eliminated.
【００２１】遂に、変圧器過負荷保護に用いる本発明の
過電流継電器の実施例を以下説明する。図２に本実施例
の構成を示す。図２において、図１と同一部分及び相当
部分については同一符号を付して説明を省略する。本実
施例では変圧器に流れている電流を入力として温度上昇
演算により変圧器を保護するための出力を発生しようと
するものである。Finally, an embodiment of the overcurrent relay of the present invention used for transformer overload protection will be described below. FIG. 2 shows the configuration of this embodiment. In FIG. 2, the same parts as those in FIG. In this embodiment, the current flowing in the transformer is used as an input to generate an output for protecting the transformer by a temperature rise calculation.
【００２２】したがって、11は保護対象とする変圧器、
12は変圧器に流れる電流を継電器2-1 に取り込むための
変流器である。過電流継電器内の構成は図１で示すとこ
ろの構成と同じであり、説明は省略する。図２の特徴は
図１の許容時間算出手段25を変圧器過負荷保護用とした
ものであり、以下にその許容時間算出のための(5) 式を
示す。Therefore, 11 is the transformer to be protected,
Reference numeral 12 is a current transformer for taking the current flowing through the transformer into the relay 2-1. The structure in the overcurrent relay is the same as that shown in FIG. 1, and the description thereof will be omitted. The feature of FIG. 2 is that the allowable time calculating means 25 of FIG. 1 is used for transformer overload protection, and the equation (5) for calculating the allowable time is shown below.
【００２３】[0023]
【数３】 この(5) 式が許容時間算出手段25にて算出され、ここで
得られた許容時間を伝送手段３により伝送する。(Equation 3) The equation (5) is calculated by the allowable time calculating means 25, and the allowable time obtained here is transmitted by the transmitting means 3.
【００２４】以上述べたように、伝送された許容時間に
より負荷しゃ断に至る前に人間系の系統操作で過負荷を
しゃ断することができ、その結果として最終的に変圧器
の過負荷を解消したかを判断することができる。As described above, the overload can be interrupted by the human system operation before the load is interrupted by the transmitted allowable time, and as a result, the overload of the transformer is finally eliminated. You can judge.
【００２５】次に、送電線過負荷保護に用いる本発明の
過電流継電器の実施例を以下説明する。図３に本実施例
の構成を示す。図３において、図１と同一部分及び相当
部分については同一符号を付して説明を省略する。本実
施例では送電線に流れている電流を入力として温度上昇
演算により送電線を保護するための出力を発生しようと
するものである。Next, an embodiment of the overcurrent relay of the present invention used for transmission line overload protection will be described below. FIG. 3 shows the configuration of this embodiment. 3, parts that are the same as or equivalent to those in FIG. 1 are assigned the same reference numerals and explanations thereof are omitted. In this embodiment, the current flowing in the power transmission line is used as an input to generate an output for protecting the power transmission line by a temperature rise calculation.
【００２６】したがって、31は保護対象とする送電線、
32は送電線に流れる電流を継電器に取り込むための変流
器である。過電流継電器内の構成は図１で示すところの
構成と同じであり、説明は省略する。図３の特徴は図１
の許容時間算出手段26を送電線過負荷保護用としたもの
であり、以下にその許容時間算出のための(6) 式を示
す。Therefore, 31 is a transmission line to be protected,
Reference numeral 32 is a current transformer for taking the current flowing through the transmission line into the relay. The structure in the overcurrent relay is the same as that shown in FIG. 1, and the description thereof will be omitted. The feature of FIG. 3 is that of FIG.
The allowable time calculating means 26 is used for transmission line overload protection, and the equation (6) for calculating the allowable time is shown below.
【００２７】[0027]
【数４】 この(6) 式が許容時間算出手段26にて計算され、ここで
得られた許容時間を伝送手段３により伝送する。(Equation 4) The equation (6) is calculated by the allowable time calculating means 26, and the allowable time obtained here is transmitted by the transmitting means 3.
【００２８】以上述べたように、伝送された許容時間に
より負荷しゃ断に至る前に人間系の系統操作で過負荷を
しゃ断することができ、その結果として最終的に送電線
の過負荷を解消したかを判断することができる。As described above, the overload can be interrupted by the system operation of the human system before the load is interrupted by the transmitted allowable time, and as a result, the overload of the transmission line is finally eliminated. You can judge.
【００２９】[0029]
【発明の効果】以上説明したように、本発明によれば過
電流継電器が過負荷に応じて負荷しゃ断を行なう時に、
当初設定した順序で負荷しゃ断を行なえない場合であっ
ても、負荷に応じた許容時間を算出して総合制御所又は
給電指令所へ伝送することで、伝送されてきた許容時間
をもとに、負荷しゃ断に至る前に系統操作により過負荷
をしゃ断することができ、更に許容時間を確認すること
で系統操作を行なった結果として、最終的に過負荷を解
消できたかを判断できる過電流継電器を提供できる。As described above, according to the present invention, when the overcurrent relay cuts off the load in response to the overload,
Even if the load cannot be cut off in the order initially set, by calculating the allowable time according to the load and transmitting it to the general control center or the power supply command center, based on the transmitted allowable time, An overcurrent relay that can cut off the overload by operating the system before the load is cut off and can finally determine whether the overload can be eliminated as a result of operating the system by checking the allowable time. Can be provided.
【図１】本発明の過電流継電器の第１の実施例の構成
図。FIG. 1 is a configuration diagram of a first embodiment of an overcurrent relay according to the present invention.
【図２】本発明の過電流継電器の第２の実施例の構成
図。FIG. 2 is a configuration diagram of a second embodiment of an overcurrent relay according to the present invention.
【図３】本発明の過電流継電器の第３の実施例の構成
図。FIG. 3 is a configuration diagram of a third embodiment of an overcurrent relay according to the present invention.
【図４】従来の過負荷継電器の特性図。FIG. 4 is a characteristic diagram of a conventional overload relay.
【図５】熱的挙動を継電器内でシミュレートした過電流
特性図。FIG. 5 is an overcurrent characteristic diagram simulating thermal behavior in a relay.
【図６】過負荷の発生によりグループ分けした負荷を順
次しゃ断する様子を示す図。FIG. 6 is a diagram showing a state in which loads divided into groups are sequentially cut off when an overload occurs.
１ 保護対象 ２，2-1 ，2-2 過電流継電器 ３ 伝送手段 21 電流データ取得手段 22 温度上昇演算手段 23 出力判定手段 24 許容時間算出手段 25 許容時間算出手段（変圧器用） 26 許容時間算出手段（送電線用） 1 Protection target 2,2-1, 2-2 Overcurrent relay 3 Transmission means 21 Current data acquisition means 22 Temperature rise calculation means 23 Output determination means 24 Allowable time calculation means 25 Allowable time calculation means (for transformer) 26 Allowable time calculation Means (for power lines)
Claims (1)
する過電流継電器において、保護対象である電力線又は
電力機器等の熱的挙動を演算する温度上昇演算手段と、
前記温度上昇演算手段により得られた温度と保護対象機
器に応じた過負荷許容限界温度との大小関係を比較して
しゃ断指令を出力する出力判定手段と、前記算出温度と
過負荷許容限界温度とにより、許容限界温度に到達する
までの許容時間を算出する許容時間算出手段と、前記許
容時間算出手段にて算出した許容時間を総合制御所又は
給電指令所へ伝送する伝送手段とを備えたことを特徴と
する過電流継電器。1. An overcurrent relay having an anti-time-limit characteristic used for overload protection, including temperature rise calculation means for calculating thermal behavior of a power line or power equipment to be protected,
Output determination means for comparing the magnitude obtained between the temperature obtained by the temperature rise computing means and the allowable overload limit temperature according to the protection target device to output a cutoff command, the calculated temperature and the allowable overload limit temperature According to the above, an allowable time calculating means for calculating the allowable time until reaching the allowable limit temperature, and a transmitting means for transmitting the allowable time calculated by the allowable time calculating means to the general control station or the power supply command station are provided. An overcurrent relay characterized by.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7183516A JPH0919050A (en) | 1995-06-27 | 1995-06-27 | Overcurrent relay |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7183516A JPH0919050A (en) | 1995-06-27 | 1995-06-27 | Overcurrent relay |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0919050A true JPH0919050A (en) | 1997-01-17 |
Family
ID=16137218
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7183516A Pending JPH0919050A (en) | 1995-06-27 | 1995-06-27 | Overcurrent relay |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0919050A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102570405A (en) * | 2010-12-27 | 2012-07-11 | 株式会社牧田 | Apparatus for electric power tool and recording medium |
-
1995
- 1995-06-27 JP JP7183516A patent/JPH0919050A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102570405A (en) * | 2010-12-27 | 2012-07-11 | 株式会社牧田 | Apparatus for electric power tool and recording medium |
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