JP3329880B2 - Superconducting coil protection system - Google Patents
Superconducting coil protection systemInfo
- Publication number
- JP3329880B2 JP3329880B2 JP7543693A JP7543693A JP3329880B2 JP 3329880 B2 JP3329880 B2 JP 3329880B2 JP 7543693 A JP7543693 A JP 7543693A JP 7543693 A JP7543693 A JP 7543693A JP 3329880 B2 JP3329880 B2 JP 3329880B2
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- JP
- Japan
- Prior art keywords
- superconducting coil
- current
- circuit breaker
- disconnector
- protection system
- Prior art date
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Description
【０００１】[0001]
【産業上の利用分野】本発明は超電導コイル保護システ
ムに係り、特に、クエンチ時に超電導コイルに蓄積され
たエネルギーを高速でダンプさせるためのクエンチ保護
装置を備えたものに好適な超電導コイル保護システムに
関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a superconducting coil protection system and, more particularly, to a superconducting coil protection system suitable for a system provided with a quench protection device for rapidly dumping energy stored in a superconducting coil during quench. .
【０００２】[0002]
【従来の技術】一般的に、断路器は電流遮断能力が無
く、数ｋＡ以上の大電流時にはアーク電圧も低くなり１
０〜２０Ｖ程度しか発生しない。2. Description of the Related Art Generally, a disconnector does not have a current interrupting capability, and when a large current of several kA or more, the arc voltage is also low and the disconnection voltage is low.
Only about 0-20V is generated.
【０００３】一方、コンデンサ転流方式の直流遮断装置
においては、直流遮断器（例えば、真空遮断器）と直列
に可飽和リアクトルが通常挿入される。この可飽和リア
クトルは、飽和時にもインダクタンスはゼロにならずに
若干の残留インダクタンスが存在し、通常５０〜１００
μＨ以下にすることは困難である。また、回路のインダ
クタンスも存在し、大電流回路になるほど装置の大型化
に伴い、回路インダクタンスも増加する。このインダク
タンスが存在するために、断路器から直流遮断器への電
流の転流は瞬時には行われず、下式に示す時間が必要と
なる。On the other hand, in a DC commutation device of the capacitor commutation type, a saturable reactor is usually inserted in series with a DC circuit breaker (for example, a vacuum circuit breaker). In this saturable reactor, the inductance does not become zero even at the time of saturation, and there is a slight residual inductance.
It is difficult to make it less than μH. In addition, circuit inductance also exists, and the circuit inductance increases as the size of the device increases as the current circuit increases. Due to the presence of this inductance, the commutation of the current from the disconnector to the DC circuit breaker is not performed instantaneously, and the time shown by the following equation is required.
【０００４】[0004]
【数１】 (Equation 1)
【０００５】ここで、Ｖａは該断路器が発生するアーク
電圧、Ｌは該断路器から該直流遮断器への転流インダク
タンス（回路インダクタンス＋可飽和リアクトルの残留
インダクタンス）である。[0005] Here, Va is the arc voltage generated by the disconnector, and L is the commutation inductance (circuit inductance + residual inductance of the saturable reactor) from the disconnector to the DC breaker.
【０００６】尚、超電導コイルの保護に関しては、特開
平3−40409号公報に開示されている。The protection of the superconducting coil is disclosed in Japanese Patent Application Laid-Open No. 3-40409.
【０００７】[0007]
【発明が解決しようとする課題】周知のように、アーク
電圧は、大電流域においては電流に対して負性特性を示
すためそれ程高くはならず、また、数ｋＡ以上では、そ
の殆どが電極から電子を放出するために必要な陰極降下
電圧によって占められる。このため、接点電極間距離を
大きくしてもアーク電圧は殆ど上昇しない。As is well known, the arc voltage does not become so high in a large current region because it exhibits a negative characteristic to the current, and when the current is several kA or more, most of the arc voltage is reduced. Occupied by the cathode drop voltage required to emit electrons from the cathode. Therefore, even if the distance between the contact electrodes is increased, the arc voltage hardly increases.
【０００８】通常用いられる接点材料(Ｃｕ，Ａｇ系合
金)で陰極降下電圧は同じような値を示し、１０〜１３
Ｖ程度である。また、アーク抵抗は、気中のプラズマ抵
抗であるが、大電流になる程プラズマ密度が増加して抵
抗が低くなり殆どゼロとなる。上記の理由により、通常
の断路器ではアーク電圧を高くするのは非常に困難であ
る。[0008] The cathode drop voltage shows a similar value for commonly used contact materials (Cu, Ag-based alloys).
About V. The arc resistance is a plasma resistance in the air, but as the current increases, the plasma density increases and the resistance decreases to almost zero. For the above reasons, it is very difficult to increase the arc voltage with a normal disconnector.
【０００９】一方、断路器の代りに、気中遮断器（ＡＣ
Ｂ）やガス遮断器（ＧＣＢ）などのアーク電圧の高い遮
断器を適用することが考えられる。しかし、現実には、
数１０ｋＡにもなる超電導コイル電流を連続通電可能な
遮断器は市販品に存在せず、製作したとしても非常に大
型かつ高価なものになる。On the other hand, instead of a disconnector, an air circuit breaker (AC
It is conceivable to apply a circuit breaker having a high arc voltage such as B) or a gas circuit breaker (GCB). But in reality,
A circuit breaker capable of continuously supplying a superconducting coil current of several tens of kA does not exist in a commercial product, and even if manufactured, it becomes very large and expensive.
【００１０】いま、Ｖａ＝２０Ｖ，Ｌ＝５０μＨ，Ｉ＝
５０ｋＡの場合を考えると、Ｔ＝１２５ｍsec となり、
この間、断路器の接点電極はアークを発生し続けること
になり、接点は大きな損傷を受けることになる。Now, Va = 20 V, L = 50 μH, I =
Considering the case of 50 kA, T = 125 msec.
During this time, the contact electrode of the disconnector will continue to generate an arc, and the contact will be severely damaged.
【００１１】このため、断路器の接点は数回程度の使用
にしか耐えられず、繰り返し使用が非常に困難であっ
た。また、超電導コイルの保護時間もその時間分遅れる
ことになり、クエンチ保護の観点からも重大な問題とな
っていた。For this reason, the contacts of the disconnector can only withstand several uses, and it is very difficult to use repeatedly. Further, the protection time of the superconducting coil is also delayed by that time, which has been a serious problem from the viewpoint of quench protection.
【００１２】本発明は上述の点に鑑みなされたもので、
その目的とするところは、アーク電圧を急激に高くし、
断路器の接点電極の損傷を抑制すると共に、直流遮断器
への電流の転流を高速化し、クエンチ保護を有効に行わ
せしめることが可能な超電導コイル保護システムを提供
するにある。The present invention has been made in view of the above points,
The purpose is to increase the arc voltage rapidly,
An object of the present invention is to provide a superconducting coil protection system capable of suppressing damage to a contact electrode of a disconnector, speeding up commutation of a current to a DC breaker, and effectively performing quench protection.
【００１３】[0013]
【課題を解決するための手段】本発明は直流遮断器と並
列に接続され、直流遮断能力は無いが大電流連続通電能
力を有する断路器の開極時に、該断路器の接点電極間に
高圧空気を吹き付ける空気吹き付け手段を備えているこ
とを特徴とする。SUMMARY OF THE INVENTION According to the present invention, a high voltage is applied between the contact electrodes of a disconnector which is connected in parallel with a DC breaker and has no DC cutoff capability but has a large current continuous conduction capability. An air blowing means for blowing air is provided.
【００１４】[0014]
【作用】本発明における空気タンクと電磁弁および空気
ノズルからなる空気吹き付け手段は、前記断路器の接点
電極の開極と連動して電磁弁を開き、接点間に発生する
アークプラズマに空気ノズルから高圧空気を吹き付ける
ことによりプラズマを冷却し、拡散させることによりプ
ラズマ密度を下げて、接点間アーク電圧を上昇させる。
これにより、アーク電圧を１０倍以上に上昇させること
が可能となり、前記（数１）式からも分かるように、転
流時間が１０倍以上短縮可能となる。The air blowing means comprising the air tank, the solenoid valve and the air nozzle according to the present invention opens the solenoid valve in conjunction with the opening of the contact electrode of the disconnector, and causes the arc nozzle to generate arc plasma between the contacts from the air nozzle. The plasma is cooled by blowing high-pressure air, and the plasma density is reduced by diffusing the plasma to increase the arc voltage between the contacts.
As a result, the arc voltage can be increased by a factor of 10 or more, and as can be seen from Equation (1), the commutation time can be reduced by a factor of 10 or more.
【００１５】このため、従来、数回程度で寿命をきたし
ていた断路器も数１０回以上の使用が可能になる。ま
た、直流遮断までの持ち時間（転流時間）も１／１０以
下に短縮されることになり、効果的なクエンチ保護が可
能になる。[0015] For this reason, the disconnector, which has conventionally had a life of only several times, can be used several tens of times or more. In addition, the holding time (commutation time) until DC interruption is also reduced to 1/10 or less, and effective quench protection can be achieved.
【００１６】[0016]
【実施例】以下、図示した実施例に基づいて本発明を詳
細に説明する。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments.
【００１７】図１に本発明の超電導コイル保護システム
の一実施例を示す。FIG. 1 shows an embodiment of a superconducting coil protection system according to the present invention.
【００１８】該図に示すごとく、交直変換装置１と保護
対象である超電導コイル５が並列に接続され、その途中
には直流遮断能力は無いが大電流連続通電能力を有する
断路器４が直列に接続されている。この断路器４には真
空遮断器３と可飽和リアクトルＬ１から成る大電流連続
通電能力は無いが遮断能力を有する直流遮断器１１が並
列に接続され、更に、この直流遮断器１１と並列に、ク
エンチ時に超電導コイル５の蓄積エネルギーを吸収する
クエンチ保護抵抗器２が接続されて基本的な回路が構成
されている。As shown in FIG. 1, an AC / DC converter 1 and a superconducting coil 5 to be protected are connected in parallel, and a disconnector 4 having no DC cutoff capability but having a large current continuous conduction capability is connected in series along the way. It is connected. The disconnecting device 4 is connected in parallel with a DC circuit breaker 11 having a vacuum circuit breaker 3 and a saturable reactor L1 which does not have a large current continuous energizing capability but has a breaking capability, and further in parallel with the DC circuit breaker 11, The quench protection resistor 2 that absorbs the energy stored in the superconducting coil 5 during quench is connected to form a basic circuit.
【００１９】そして、通常時は交直変換装置１から直流
遮断器１１と並列に接続された断路器４を介して超電導
コイル５を励磁する一方、クエンチ時には断路器４を開
極して電流を直流遮断器１１に転流せしめ、その後、該
直流遮断器１１にて電流を遮断して電流をクエンチ保護
抵抗器１１に移し、超電導コイル５の蓄積エネルギーを
吸収するようにして超電導コイル５を保護している。In the normal state, the superconducting coil 5 is excited from the AC / DC converter 1 via the disconnector 4 connected in parallel with the DC circuit breaker 11, while the disconnector 4 is opened at the time of quenching to supply the DC current. It is commutated to the circuit breaker 11, and then the current is cut off by the DC circuit breaker 11, the current is transferred to the quench protection resistor 11, and the superconducting coil 5 is protected by absorbing the accumulated energy of the superconducting coil 5. ing.
【００２０】上記のような回路構成において、本実施例
では断路器４の開極時に、該断路器４の接点電極間に高
圧空気を吹き付けるための空気ノズル６と電磁弁７およ
び空気タンク８から構成される空気吹き付け手段を設け
ている。In the circuit configuration described above, in this embodiment, when the disconnector 4 is opened, the air nozzle 6 for blowing high-pressure air between the contact electrodes of the disconnector 4, the electromagnetic valve 7, and the air tank 8 are used. An air blowing means is provided.
【００２１】図２にこの空気吹き付け手段を備えた断路
器４の具体的構成を示す。FIG. 2 shows a specific structure of the disconnector 4 provided with the air blowing means.
【００２２】該図に示すごとく、断路器４は、通常の電
流を流す多数の通電接点９と、電流遮断用で、かつ、空
気ノズル６を備えた少数のアーク接点１０からなる。各
接点は連動し、空気シリンダ１３により駆動される。通
電接点９は、一斉に開極し、それより少し遅れて(数ｍs
ec )アーク接点１０が開極するように構成されているた
め、電流通電時に断路器４を開極すると、常時通電接点
９に流れていた電流が、まだ開極していないアーク接点
１０に転流する。通電接点９とアーク接点１０は極めて
隣接した配置構成にしてあるので、転流時間は１ｍsec
以下であり、また通電接点９は多数の通電接点９により
分流されているために、主電流の数分の１程度であるた
め接点の損傷は殆どない。As shown in the figure, the disconnector 4 comprises a large number of energizing contacts 9 for passing a normal current, and a small number of arc contacts 10 for interrupting the current and having an air nozzle 6. Each contact is linked and driven by the air cylinder 13. The current-carrying contacts 9 are simultaneously opened, and a little later (several ms)
ec) Since the arc contact 10 is configured to be opened, when the disconnector 4 is opened when current is supplied, the current flowing through the current-carrying contact 9 is transferred to the arc contact 10 that has not been opened yet. Shed. The commutation time is 1 msec because the current-carrying contact 9 and the arc contact 10 are arranged very close to each other.
Since the current-carrying contact 9 is divided by a large number of current-carrying contacts 9 and is only a fraction of the main current, the contact is hardly damaged.
【００２３】転流後は、アーク接点１０に全電流が流
れ、その後、アーク接点１０が開極し、アークが発生す
る。一方、アーク接点１０が開極する少し前(数ｍsec )
に、電磁弁７を開いておき、予め高圧（数kgf／cm2）を
空気ノズル６から吹き付けておく。接点間アークは、高
速空気流の中で発生することになり、アーク電圧は著し
く上昇し、１００Ｖから数１００Ｖにも達する。After commutation, the entire current flows through the arc contact 10, and thereafter, the arc contact 10 is opened, and an arc is generated. On the other hand, shortly before the arc contact 10 opens (a few msec)
Then, the solenoid valve 7 is opened, and high pressure (several kgf / cm 2 ) is blown from the air nozzle 6 in advance. The arc between the contacts will occur in a high-speed air flow, and the arc voltage will increase significantly, reaching from 100V to several hundreds of volts.
【００２４】このアーク電圧を転流起電力として、接点
電流が直流遮断器１１に速やかに転流する。転流時間は
前記（数１）式で計算でき、前出例の定数を用いアーク
電圧Ｖａを３００Ｖとすると８.３ｍsecとなる。このよ
うに、転流時間を大幅に短縮することが可能となる。Using the arc voltage as the commutation electromotive force, the contact current commutates to the DC breaker 11 quickly. The commutation time can be calculated by the above formula (Equation 1), and is 8.3 msec when the arc voltage Va is 300 V using the constant of the above example. Thus, the commutation time can be significantly reduced.
【００２５】このような本実施例の構成によると、クエ
ンチ保護時間が大幅に短縮できると共に、断路器の繰り
返し寿命が大幅に増加する。また、断路器を多数の通電
接点と少数のアーク接点とで構成し、アーク接点のみに
空気吹き付け機構を設けることにより、安価に製作で
き、高価な接点材料（耐弧メタル）はアーク接点のみに
用いれば良いので、断路器自体も安価に製作できるし、
メンテナンス(接点交換)もアーク接点のみで良いため、
保守費用も安価になる。更に、高価で大型のACB,ＧＣＢ
を使用することなく、安価で小型の断路器で超電導コイ
ル保護システムが構成できるという効果がある。According to the configuration of this embodiment, the quench protection time can be greatly reduced, and the repetition life of the disconnector is greatly increased. In addition, the disconnector is composed of a large number of current-carrying contacts and a small number of arc contacts, and by providing an air blowing mechanism only to the arc contacts, it can be manufactured at low cost. Since it can be used, the disconnector itself can be manufactured at low cost,
Maintenance (contact replacement) can be done only with arc contacts.
Maintenance costs are also lower. In addition, expensive and large ACB, GCB
There is an effect that a superconducting coil protection system can be configured with an inexpensive and small disconnector without using a power supply.
【００２６】[0026]
【発明の効果】以上説明した本発明の超電導コイル保護
システムによれば、直流遮断器と並列に接続され、直流
遮断能力は無いが大電流連続通電能力を有する断路器の
開極時に、該断路器の接点電極間に高圧空気を吹き付け
る空気吹き付け手段を備えているものであるから、接点
間に発生するアークプラズマに空気吹き付け手段によ
り、高圧空気を吹き付けることができるので、アーク電
圧を急激に高くすることができ、断路器の接点電極の損
傷を抑制すると共に、直流遮断器への電流の転流を高速
化し、クエンチ保護を有効に行わせしめることができ
る、という効果がある。According to the superconducting coil protection system of the present invention described above, when the disconnecting switch is connected in parallel with the DC breaker and has no DC blocking capability but has a large continuous current carrying capability, the disconnection of the disconnector is prevented. Since air blowing means for blowing high-pressure air between the contact electrodes of the heater is provided, high-pressure air can be blown by the air blowing means to the arc plasma generated between the contacts, so that the arc voltage is rapidly increased. This has the effect of suppressing damage to the contact electrode of the disconnector, increasing the speed of commutation of current to the DC breaker, and effectively performing quench protection.
【図１】本発明の超電導コイル保護システムの一実施例
を示す回路図である。FIG. 1 is a circuit diagram showing one embodiment of a superconducting coil protection system of the present invention.
【図２】本発明の超電導コイル保護システムを構成する
断路器の具体的な構成図である。FIG. 2 is a specific configuration diagram of a disconnector constituting the superconducting coil protection system of the present invention.
１…交直変換装置、２…クエンチ保護抵抗器、３…真空
遮断器、４…断路器、５…超電導コイル、６…空気ノズ
ル、７…電磁弁、８…空気タンク、９…通電接点、１０
…アーク接点、１１…直流遮断器、１３…空気シリン
ダ。DESCRIPTION OF SYMBOLS 1 ... AC / DC converter, 2 ... Quench protection resistor, 3 ... Vacuum breaker, 4 ... Disconnector, 5 ... Superconducting coil, 6 ... Air nozzle, 7 ... Solenoid valve, 8 ... Air tank, 9 ... Electric contact, 10
... Arc contacts, 11 ... DC breakers, 13 ... Air cylinders.
フロントページの続き (72)発明者 久保 守弘 茨城県日立市幸町三丁目２番２号 株式 会社 日立エンジニアリングサービス内 (72)発明者 佐藤 徹 愛知県春日井市愛知町１番地 愛知電機 株式会社内 審査官 山田 正文 (58)調査した分野(Int.Cl.7，ＤＢ名) H01F 6/00 ZAA H01H 31/00 H01H 33/00 Continuing from the front page (72) Inventor Morihiro Kubo 3-2-2, Sachimachi, Hitachi City, Ibaraki Prefecture Within Hitachi Engineering Services Co., Ltd. (72) Inventor Tohru Sato 1st Aichi-cho, Kasugai-shi, Aichi Pref. Official Masafumi Yamada (58) Field surveyed (Int.Cl. 7 , DB name) H01F 6/00 ZAA H01H 31/00 H01H 33/00
Claims (3)
び大電流連続通電能力は無いが遮断能力を有する直流遮
断器と、該直流遮断器と並列に接続され直流遮断能力は
無いが大電流連続通電能力を有する断路器とを備え、通
常時は前記交直変換装置から前記断路器を介して超電導
コイルを励磁する一方、クエンチ時には前記断路器を開
極して電流を前記直流遮断器に転流せしめた後、該直流
遮断器にて電流を遮断して電流を前記クエンチ保護抵抗
器に移し、前記超電導コイルの蓄積エネルギーを吸収す
るようにした超電導コイル保護システムにおいて、前記
断路器の開極時に、該断路器の接点電極間に高圧空気を
吹き付ける空気吹き付け手段を備えていることを特徴と
する超電導コイル保護システム。An AC / DC converter, a quench protection resistor and a DC circuit breaker having no continuous current carrying capability but having a breaking capability, and a DC breaker connected in parallel with the DC circuit breaker but having no DC breaking capability but a large continuous current. and a disconnector with current capacity, while the normal to excite the superconducting coil via the disconnecting switch from the AC-DC converter, commutation the current by opening the disconnecting switch during quenching to the DC circuit breaker After that, in the superconducting coil protection system in which the current is cut off by the DC circuit breaker and the current is transferred to the quench protection resistor to absorb the energy stored in the superconducting coil, when the disconnecting switch is opened, A superconducting coil protection system comprising air blowing means for blowing high-pressure air between contact electrodes of the disconnector.
磁弁および空気タンクから構成されていることを特徴と
する請求項１記載の超電導コイル保護システム。2. The superconducting coil protection system according to claim 1, wherein said air blowing means comprises an air nozzle, a solenoid valve, and an air tank.
クトルから成り、該直流遮断器と並列に前記断路器が接
続され、該真空遮断器と並列にクエンチ保護抵抗器が接
続されていることを特徴とする請求項１記載の超電導コ
イル保護システム。3. The DC circuit breaker comprises a vacuum circuit breaker and a saturable rear circuit.
And the disconnector is connected in parallel with the DC circuit breaker.
The quench protection resistor is connected in parallel with the vacuum circuit breaker.
Superconducting coil protection system according to claim 1, characterized in that it is continued.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7543693A JP3329880B2 (en) | 1993-04-01 | 1993-04-01 | Superconducting coil protection system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7543693A JP3329880B2 (en) | 1993-04-01 | 1993-04-01 | Superconducting coil protection system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH06290940A JPH06290940A (en) | 1994-10-18 |
| JP3329880B2 true JP3329880B2 (en) | 2002-09-30 |
Family
ID=13576186
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7543693A Expired - Fee Related JP3329880B2 (en) | 1993-04-01 | 1993-04-01 | Superconducting coil protection system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3329880B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5452555B2 (en) * | 2011-08-29 | 2014-03-26 | 株式会社日立製作所 | Switchgear and switchgear operating method |
| WO2013164875A1 (en) | 2012-05-01 | 2013-11-07 | 三菱電機株式会社 | Dc circuit breaker |
-
1993
- 1993-04-01 JP JP7543693A patent/JP3329880B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH06290940A (en) | 1994-10-18 |
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