JP2773763B2 - High-voltage three-phase distribution line phase switching device - Google Patents
High-voltage three-phase distribution line phase switching deviceInfo
- Publication number
- JP2773763B2 JP2773763B2 JP5061736A JP6173693A JP2773763B2 JP 2773763 B2 JP2773763 B2 JP 2773763B2 JP 5061736 A JP5061736 A JP 5061736A JP 6173693 A JP6173693 A JP 6173693A JP 2773763 B2 JP2773763 B2 JP 2773763B2
- Authority
- JP
- Japan
- Prior art keywords
- switch
- phase
- current
- distribution line
- switching device
- 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 - Fee Related
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E40/00—Technologies for an efficient electrical power generation, transmission or distribution
- Y02E40/50—Arrangements for eliminating or reducing asymmetry in polyphase networks
Landscapes
- Testing Electric Properties And Detecting Electric Faults (AREA)
- Supply And Distribution Of Alternating Current (AREA)
Description
【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION
【0001】[0001]
【産業上の利用分野】本発明は、三相負荷電流の不平衡
が大きい高圧三相配電線において、単相負荷が接続され
ている相を残りの相に切り替えるために使用される高圧
三相配電線の相切替装置に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-voltage three-phase distribution line used for switching a phase connected to a single-phase load to a remaining phase in a high-voltage three-phase distribution line having a large three-phase load current imbalance. ).
【0002】[0002]
【従来の技術】高圧三相配電線に対する単相負荷の接続
は、三相中の任意の二相に対して行われることとなる
が、実際の系統においては単相負荷が特定の二相に集中
して接続されることが多い。このような場合には三相負
荷電流の不平衡状態を招き、電力設備の利用効率が悪く
なったり、三相誘導モータ等の負荷にも悪影響を及ぼし
たりする。2. Description of the Related Art A single-phase load is connected to a high-voltage three-phase distribution line for any two of the three phases, but in an actual system, the single-phase load is concentrated on a specific two-phase. Often connected. In such a case, an unbalanced state of the three-phase load current is caused, and the utilization efficiency of the power equipment deteriorates, and the load of the three-phase induction motor or the like is adversely affected.
【0003】そこでこのような場合には、単相負荷が接
続されている相を残りの相に切り替えることにより三相
負荷電流の不平衡を減少させることが考えられる。とこ
ろがこのためには長時間の停電工事を必要とするので、
通常は相の切り替えを行うことなく運用されていること
が多かった。In such a case, it is conceivable to reduce the unbalance of the three-phase load current by switching the phase to which the single-phase load is connected to the remaining phase. However, this requires long-term blackout work,
Usually, they were operated without switching the phases.
【0004】上記の実情に鑑み、本発明者等は実質的に
無停電で相の切り替えを行うことができる相切替装置を
発明し、既に特願平4-228772号として特許出願した。こ
の先願の相切替装置は、図7に示すように配電線の切断
される相bの切断点Xと並列に第1開閉器1を取り付け
るとともに、前記切断点Xよりも負荷L側の点と接続さ
れる相cとの間に、第1開閉器1の開路に引続き高速で
閉動作を行う無接点開閉器3を取り付け、さらにこの無
接点開閉器3と並列にその閉動作に引続き閉動作を行う
第2開閉器2を取り付けたものである。In view of the above circumstances, the present inventors have invented a phase switching device capable of performing phase switching substantially without power interruption, and have already applied for a patent as Japanese Patent Application No. 4-228772. In the phase switching device of the prior application, as shown in FIG. 7, the first switch 1 is attached in parallel with a cutting point X of a phase b where a distribution line is cut, and a point closer to a load L than the cutting point X is connected. A non-contact switch 3 that performs a high-speed closing operation following the opening of the first switch 1 is attached between the connected phase c and the closing operation following the closing operation in parallel with the non-contact switch 3. And a second switch 2 for performing the above operation.
【0005】この相切替装置は、第1開閉器1をオンと
して切断点Xを切断したうえ、第1開閉器1をオフとす
ると同時に無接点開閉器3をオンとして瞬時に相の切り
替えを行い、更に第2開閉器2を閉じたうえで第2開閉
器2と並列に結線を行うという手順で工事を進行するた
めのものである。しかしこの先願の相切替装置におい
て、例えば第1開閉器が開放されていないにもかかわら
ず無接点開閉器を投入した場合には、相間短絡事故が発
生するおそれがあった。In this phase switching device, the first switch 1 is turned on to cut off the cutting point X, and at the same time, the first switch 1 is turned off, and at the same time, the non-contact switch 3 is turned on to instantaneously switch phases. Further, the construction is performed in such a manner that the second switch 2 is closed and then the second switch 2 is connected in parallel. However, in the phase switching device of the prior application, for example, when the non-contact switch is turned on even though the first switch is not opened, there is a possibility that an inter-phase short-circuit accident may occur.
【0006】[0006]
【発明が解決しようとする課題】本発明は上記した従来
の問題点を解決して、無停電で相の切り替えを行うこと
ができ、しかも短絡事故等の可能性を完全に防止できる
高圧三相配電線の相切替装置を提供するために完成され
たものである。SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems in the prior art, and enables high-voltage three-phase distribution in which phase switching can be carried out without interruption and completely preventing the possibility of a short circuit accident or the like. It has been completed to provide a phase switching device for electric wires.
【0007】[0007]
【課題を解決するための手段】上記の課題を解決するた
めになされた本発明は、配電線の切断される相の切断点
と並列に第1開閉器を取り付けるとともに、前記切断点
よりも負荷側の点と接続される相との間に第1開閉器の
開路に引続き高速で閉動作を行う無接点開閉器を取り付
け、さらにこの無接点開閉器と並列にその閉動作に引続
き閉動作を行う第2開閉器を取り付けた相切替装置にお
いて、各開閉器に電流検出手段を設けるとともに、各開
閉器が動作する度に電流を検出して相の切替えを行って
いく制御装置を設けたことを特徴とするものである。SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a first switch mounted in parallel with a cutting point of a phase where a distribution line is cut, and a load which is higher than the cutting point. A non-contact switch that performs a high-speed closing operation following the opening of the first switch between the side point and the connected phase, and further closes the closing operation in parallel with the non-contact switching unit. In the phase switching device equipped with the second switch to be performed, a current detecting means is provided in each switch, and a control device is provided which detects a current and switches a phase each time each switch operates. It is characterized by the following.
【0008】[0008]
【作用】本発明の高圧三相配電線の相切替装置は、各開
閉器に取り付けた電流検出手段により各開閉器の動作を
確認しつつ制御装置が相の切替えを進行するので、短絡
事故の発生を完全に防止しつつ相の切替えを完了するこ
とができる。なお、具体的な構成及び手順は次の実施例
によって詳細に説明する。In the phase switching device for high-voltage three-phase distribution lines according to the present invention, the control device advances the phase switching while confirming the operation of each switch by the current detecting means attached to each switch. Can be completed while the phase switching is completed. The specific configuration and procedure will be described in detail with reference to the following examples.
【0009】[0009]
【実施例】〔実施例1〕図1は第1の実施例の構成を示
す回路図であり、a,b,cの三相配電線のa−b間に
接続されている負荷Lをa−c間に切り替える例を示し
ている。ここでbを切断される相、cを接続される相、
Xを切断点とする。また1は切断される相bの切断点X
と並列に取り付けられた有接点式の第1開閉器(SW
)、3は切断点Xよりも負荷L側の点と接続される相
bとの間に設けられ、第1開閉器1の開路に引続き高速
で閉動作を行う無接点開閉器(SCR)である。この
無接点開閉器3としては例えばサイリスタのような半導
体を利用した半導体スイッチが用いられる。更に2はこ
の無接点開閉器3と並列に取り付けられ、無接点開閉器
3の閉動作に引続き閉動作を行う第2開閉器(SW)
である。[Embodiment 1] FIG. 1 is a circuit diagram showing a configuration of a first embodiment, in which a load L connected between a and b of a three-phase distribution line a, b and c is connected to a-a. An example is shown in which switching is made between c. Where b is the phase to be disconnected, c is the phase to be connected,
Let X be the cutting point. 1 is a cutting point X of the phase b to be cut.
Contact type first switch (SW
) 3 is a non-contact switch (SCR) provided between the point on the load L side of the disconnection point X and the connected phase b and performs a high-speed closing operation following the opening of the first switch 1. is there. As the non-contact switch 3, a semiconductor switch using a semiconductor such as a thyristor is used, for example. A second switch (SW) 2 is mounted in parallel with the contactless switch 3 and performs a closing operation following the closing operation of the contactless switch 3.
It is.
【0010】本発明においては、これらの第1開閉器
1、第2開閉器2、無接点開閉器3の電源側にCTのよ
うな電流検出手段4(CT)、5(CT)、6(C
T)を取り付け、各開閉器の動作を確認できるように
してある。これらの電流検出手段4、5、6の出力は制
御装置7に入力されている。また制御装置7は第1開閉
器1、第2開閉器2、無接点開閉器3にそれぞれ接続さ
れ、これらの開閉動作を制御することができるようにな
っている。In the present invention, current detecting means 4 (CT) such as CT, 5 (CT), and 6 (CT) are provided on the power supply side of the first switch 1, the second switch 2, and the contactless switch 3. C
T) is attached so that the operation of each switch can be checked. Outputs of these current detecting means 4, 5, and 6 are input to the control device 7. The control device 7 is connected to each of the first switch 1, the second switch 2, and the contactless switch 3, and can control the opening and closing operations of these switches.
【0011】次に図2を参照しつつ図1の装置の動作を
説明する。まず三相配電線のケーブルに図1のように各
機器を接続したうえ、第1開閉器1(SW)をオンと
する。このとき電流検出手段4(CT)に電流が流れ
ていることを制御装置7が確認し、もし電流が流れてい
ない場合には異常警報を発して動作を停止する。また電
流検出手段4(CT)に電流が流れていることが確認
されたときには、制御装置7が電線切断の指示を出し切
断される相bを切断点Xから切断する。Next, the operation of the apparatus shown in FIG. 1 will be described with reference to FIG. First, each device is connected to the cable of the three-phase distribution line as shown in FIG. 1, and the first switch 1 (SW) is turned on. At this time, the control device 7 confirms that a current is flowing to the current detecting means 4 (CT), and if no current is flowing, issues an abnormal alarm and stops the operation. When it is confirmed that a current is flowing through the current detecting means 4 (CT), the control device 7 issues an instruction to cut the electric wire and cuts the phase b to be cut from the cutting point X.
【0012】次に第1開閉器1(SW)をオフとし、
これに引続き制御装置7が無接点開閉器3(SCR)
を高速でオンとするが、本発明では第1開閉器1(SW
)をオフとした直後に、電流検出手段4(CT)に
電流が流れていないことを制御装置7が確認する。もし
第1開閉器1(SW)をオフとしたにもかかわらず電
流検出手段4(CT)に電流が流れていれば、第1開
閉器1(SW)がオフしていない等の異常があるの
で、直ちに異常警報を発し動作を停止する。Next, the first switch 1 (SW) is turned off,
Subsequently, the control device 7 switches the contactless switch 3 (SCR).
Is turned on at high speed, but in the present invention, the first switch 1 (SW
) Is turned off, the control device 7 confirms that no current is flowing through the current detecting means 4 (CT). If a current flows through the current detecting means 4 (CT) even though the first switch 1 (SW) is turned off, there is an abnormality such as the first switch 1 (SW) is not turned off. Therefore, an abnormal alarm is immediately issued and the operation is stopped.
【0013】正常であることが確認されれば、制御装置
7が無接点開閉器3(SCR)を高速でオンとしたう
えで電流検出手段6(CT)に電流が流れていること
を確認する。無接点開閉器3(SCR)をオンとした
ことにより相切り替えができたこととなるが、無接点開
閉器3(SCR)に長時間電流を流すことを避けるた
めにこれに引続き制御装置7が第2開閉器(SW)を
閉じる。このため、無接点開閉器3(SCR)をオン
としたにもかかわらず電流検出手段6(CT)が電流
を検出しない場合にも、警報を発するだけで第2開閉器
(SW)を閉じる。If it is confirmed that the operation is normal, the control device 7 turns on the non-contact switch 3 (SCR) at a high speed and confirms that a current is flowing through the current detecting means 6 (CT). . Turning on the non-contact switch 3 (SCR) means that the phase can be switched. However, in order to prevent a long-time current from flowing through the non-contact switch 3 (SCR), the control device 7 continues to operate. The second switch (SW) is closed. For this reason, even when the current detection means 6 (CT) does not detect a current even though the non-contact switch 3 (SCR) is turned on, the second switch (SW) is closed only by issuing an alarm.
【0014】そして電流検出手段5(CT)に電流が
流れていることを確認したうえで破線で示すように電線
を結線する。しかし、もし電流検出手段5(CT)に
電流が流れていない場合には第2開閉器(SW)がオ
ンとなっていないため、異常警報を発して動作を停止す
る。このようにして電線の結線を完了したら、無接点開
閉器3(SCR)と第2開閉器(SW)をオフとし
て各機器を取り外し、全ての作業が完了する。After confirming that a current is flowing through the current detecting means 5 (CT), the electric wire is connected as shown by a broken line. However, if no current is flowing through the current detection means 5 (CT), the second switch (SW) is not turned on, so that an abnormal alarm is issued and the operation is stopped. When the connection of the electric wires is completed in this way, the non-contact switch 3 (SCR) and the second switch (SW) are turned off, and each device is removed, and all operations are completed.
【0015】なお、相切り替えの瞬間における各開閉器
の動作のタイムチャートを図3に示す。このタイムチャ
ートにTとして示された時間が停電時間となるが、その
長さは商用周波数の半サイクル程度で済むので、ほとん
ど無停電で相切り替え工事を行えることとなる。FIG. 3 shows a time chart of the operation of each switch at the moment of phase switching. The time indicated by T in this time chart is the power outage time, but the length is only about half a cycle of the commercial frequency, so that the phase switching work can be performed almost without power outage.
【0016】〔実施例2〕図4は第2の実施例の構成を
示す回路図であり、図1における第1開閉器(SW)
と並列に無接点開閉器8(SCR)を取り付けた点の
みが第1の実施例と相違する。図5は第2の実施例の動
作を示すフローチャートであるが、第1の実施例では第
1開閉器(SW)をオフとし、電流検出手段4(CT
)に電流が流れていないことを確認してこれに引続き
無接点開閉器3(SCR)を高速でオンとする。これ
に対して、第2の実施例では第1開閉器(SW)をオ
フとする前に無接点開閉器8(SCR)をオンとす
る。そして無接点開閉器8(SCR)をオフとして電
流検出手段4(CT)に電流が流れていないことを確
認したうえで、無接点開閉器3(SCR)を高速でオ
ンとする。またもし無接点開閉器8(SCR)をオフ
としたにもかかわらず電流検出手段4(CT)に電流
が流れている場合には、無接点開閉器8(SCR)が
オフとなっていないため、短絡事故を防止するために第
1開閉器(SW)をオンとしたのち警報を発して動作
を停止する。その他の部分は図2と同様である。なお、
図6は第2の実施例の動作を示すタイムチャートであ
り、無接点開閉器8(SCR)を取り付けたことによ
り停電時間tがより短くなったことが分かる。[Embodiment 2] FIG. 4 is a circuit diagram showing a configuration of a second embodiment, and a first switch (SW) shown in FIG.
Only the point that a non-contact switch 8 (SCR) is attached in parallel with the first embodiment differs from the first embodiment. FIG. 5 is a flowchart showing the operation of the second embodiment. In the first embodiment, the first switch (SW) is turned off, and the current detecting means 4 (CT
), It is confirmed that no current flows, and subsequently, the non-contact switch 3 (SCR) is turned on at a high speed. On the other hand, in the second embodiment, the non-contact switch 8 (SCR) is turned on before the first switch (SW) is turned off. Then, the non-contact switch 8 (SCR) is turned off, and after confirming that no current flows through the current detecting means 4 (CT), the non-contact switch 3 (SCR) is turned on at a high speed. If the current is flowing through the current detecting means 4 (CT) even though the non-contact switch 8 (SCR) is turned off, the non-contact switch 8 (SCR) is not turned off. After the first switch (SW) is turned on to prevent a short circuit accident, an alarm is issued and the operation is stopped. Other parts are the same as those in FIG. In addition,
FIG. 6 is a time chart showing the operation of the second embodiment, and it can be seen that the blackout time t has become shorter due to the attachment of the non-contact switch 8 (SCR).
【0017】[0017]
【発明の効果】以上に説明したように、本発明の高圧三
相配電線の相切替装置は、実質的に無停電で相の切り替
えを行うことができ、しかも各開閉器に電流検出手段を
設けて各開閉器が動作する度に電流を検出して相の切替
えを行っていくようにしたので、短絡事故等の可能性を
完全に防止することができる。よって本発明は従来の問
題点を解決した高圧三相配電線の相切替装置として、産
業の発展に寄与するところはきわめて大きいものであ
る。As described above, the phase switching device for a high-voltage three-phase distribution line according to the present invention can perform phase switching substantially without interruption, and furthermore, each switch is provided with current detecting means. Thus, each time each switch operates, current is detected and phase switching is performed, so that the possibility of a short circuit accident or the like can be completely prevented. Therefore, the present invention greatly contributes to industrial development as a phase switching device for a high-voltage three-phase distribution line that solves the conventional problems.
【図1】第1の実施例の構成を示す回路図である。FIG. 1 is a circuit diagram showing a configuration of a first embodiment.
【図2】第1の実施例の装置の動作を説明するフローチ
ャートである。FIG. 2 is a flowchart illustrating the operation of the apparatus according to the first embodiment.
【図3】第1の実施例の装置における、相切替え動作の
タイムチャートである。FIG. 3 is a time chart of a phase switching operation in the device of the first embodiment.
【図4】第2の実施例の構成を示す回路図である。FIG. 4 is a circuit diagram showing a configuration of a second embodiment.
【図5】第2の実施例の装置の動作を説明するフローチ
ャートである。FIG. 5 is a flowchart illustrating the operation of the device according to the second embodiment.
【図6】第2の実施例の装置における、相切替え動作の
タイムチャートである。FIG. 6 is a time chart of a phase switching operation in the device of the second embodiment.
【図7】先願の相切替装置の構成を示す回路図である。FIG. 7 is a circuit diagram showing a configuration of a phase switching device of the prior application.
1 第1開閉器(SW) 2 第2開閉器(SW) 3 無接点開閉器(SCR) 4 電流検出手段(CT) 5 電流検出手段(CT) 6 電流検出手段(CT) 7 制御装置 8 無接点開閉器(SCR) DESCRIPTION OF SYMBOLS 1 1st switch (SW) 2 2nd switch (SW) 3 Non-contact switch (SCR) 4 Current detecting means (CT) 5 Current detecting means (CT) 6 Current detecting means (CT) 7 Control device 8 None Contact switch (SCR)
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.6,DB名) H02J 3/00 - 5/00──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. 6 , DB name) H02J 3/00-5/00
Claims (2)
第1開閉器を取り付けるとともに、前記切断点よりも負
荷側の点と接続される相との間に第1開閉器の開路に引
続き高速で閉動作を行う無接点開閉器を取り付け、さら
にこの無接点開閉器と並列にその閉動作に引続き閉動作
を行う第2開閉器を取り付けた相切替装置において、各
開閉器に電流検出手段を設けるとともに、各開閉器が動
作する度に電流を検出して相の切替えを行っていく制御
装置を設けたことを特徴とする高圧三相配電線の相切替
装置。1. A first switch is mounted in parallel with a cut point of a phase of a distribution line to be cut, and the first switch is opened between a phase connected to a point on the load side of the cut point. In a phase switching device in which a non-contact switch that performs a closing operation at high speed is mounted subsequently, and a second switch that performs a closing operation following the closing operation is mounted in parallel with the non-contact switch, current is supplied to each of the switches. A phase switching device for a high-voltage three-phase distribution line, comprising: a detection device; and a control device that detects a current and switches a phase each time each switch operates.
付けたことを特徴とする請求項1記載の高圧三相配電線
の相切替装置。2. The high-voltage three-phase distribution line phase switching device according to claim 1, wherein a non-contact switch is mounted in parallel with the first switch.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP5061736A JP2773763B2 (en) | 1993-03-22 | 1993-03-22 | High-voltage three-phase distribution line phase switching device |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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JP5061736A JP2773763B2 (en) | 1993-03-22 | 1993-03-22 | High-voltage three-phase distribution line phase switching device |
Publications (2)
Publication Number | Publication Date |
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JPH06276686A JPH06276686A (en) | 1994-09-30 |
JP2773763B2 true JP2773763B2 (en) | 1998-07-09 |
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JP5061736A Expired - Fee Related JP2773763B2 (en) | 1993-03-22 | 1993-03-22 | High-voltage three-phase distribution line phase switching device |
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KR101079900B1 (en) * | 2007-10-31 | 2011-11-04 | 주식회사 케이티 | Static transfer switch device, power supply apparatus using the switch device and switching method thereof |
JP6234125B2 (en) * | 2013-09-10 | 2017-11-22 | 三菱電機株式会社 | Load change device |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
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JPS4952034U (en) * | 1972-08-14 | 1974-05-08 | ||
JPS63917A (en) * | 1986-06-18 | 1988-01-05 | 日本碍子株式会社 | Contactless switch |
JPS648837A (en) * | 1987-06-30 | 1989-01-12 | Shin Kobe Electric Machinery | Ac no-break power unit |
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1993
- 1993-03-22 JP JP5061736A patent/JP2773763B2/en not_active Expired - Fee Related
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Publication number | Publication date |
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JPH06276686A (en) | 1994-09-30 |
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