JPH1022149A - Zero-phase current transformer - Google Patents
Zero-phase current transformerInfo
- Publication number
- JPH1022149A JPH1022149A JP8188384A JP18838496A JPH1022149A JP H1022149 A JPH1022149 A JP H1022149A JP 8188384 A JP8188384 A JP 8188384A JP 18838496 A JP18838496 A JP 18838496A JP H1022149 A JPH1022149 A JP H1022149A
- Authority
- JP
- Japan
- Prior art keywords
- zero
- current transformer
- phase current
- conductors
- terminal
- 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
Landscapes
- Regulation Of General Use Transformers (AREA)
- Transformers For Measuring Instruments (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、小形で安価な市場
ニーズに対応した漏電ブレーカーに用いる小形で高性能
な不平衡特性を有する零相変流器に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small, high-performance zero-phase current transformer having an unbalanced characteristic for use in an earth leakage breaker which is small and inexpensive and meets market needs.
【０００２】[0002]
【従来の技術】零相変流器は、中央の貫通孔に往復電線
を通し、交流電流を流し、漏電等による異常時の往復電
線に生じる電流差を、磁芯に均一に巻回した巻線を介し
て電圧として検出する機能を持ち、漏電ブレーカー等に
組み込まれて漏電を検出するという重要な機能を持つ。2. Description of the Related Art In a zero-phase current transformer, a reciprocating electric wire is passed through a central through-hole, an alternating current is applied, and a current difference generated in the reciprocating electric wire in the event of an abnormality due to leakage or the like is uniformly wound around a magnetic core. It has a function of detecting as a voltage via a wire, and has an important function of being incorporated in an earth leakage breaker or the like to detect earth leakage.
【０００３】零相変流器は、往復電線に生じる交流電流
の差を電圧として検出する動作と、往復電線に突入電流
等の大電流が印加した時においても、漏電ブレーカーが
誤動作しない平衡特性が求められ、その方策としては、
巻線を巻回した磁心の上下面に軟磁性材からなるシール
ドリングを適当枚数装着し、磁気シールド効果を持たせ
ている。[0003] The zero-phase current transformer has an operation of detecting a difference between alternating currents generated in a reciprocating electric wire as a voltage and a balance characteristic in which an earth leakage breaker does not malfunction even when a large current such as an inrush current is applied to the reciprocating electric wire. Is required, and as a measure,
Appropriate number of shield rings made of a soft magnetic material are mounted on the upper and lower surfaces of the magnetic core around which the winding is wound to provide a magnetic shielding effect.
【０００４】図５は、従来の零相変流器の一例を示す図
である。この従来の零相変流器は、樹脂製のホルダー５
の貫通孔１６の内部に複数の一次導体７を通して、内部
のトロイダルコイルの巻線の端子８を漏電ブレーカー等
に接続して使用する。FIG. 5 is a diagram showing an example of a conventional zero-phase current transformer. This conventional zero-phase current transformer has a resin holder 5.
The terminal 8 of the winding of the toroidal coil inside is connected to an earth leakage breaker or the like through a plurality of primary conductors 7 inside the through hole 16 for use.
【０００５】[0005]
【発明が解決しようとする課題】従来の零相変流器は、
樹脂製のホルダー５の貫通孔１６の内部に一次導体７の
位置を特定する支持部を持たないため、一次導体の電流
による二次電圧の関係を示す不平衡特性に個体差が生
じ、良好な不平衡特性を得るための位置決めは、熟練し
た技能が必要であった。A conventional zero-phase current transformer is:
Since there is no supporting portion for specifying the position of the primary conductor 7 inside the through hole 16 of the resin holder 5, individual differences occur in the unbalance characteristics indicating the relationship of the secondary voltage due to the current of the primary conductor, and a good Positioning to obtain the unbalanced property required a skilled skill.
【０００６】又、複数の一次導体間の絶縁、耐圧特性の
向上のため、一次導体間の距離を十分にとる必要があっ
た。[0006] In addition, in order to improve insulation and withstand voltage characteristics between a plurality of primary conductors, it is necessary to provide a sufficient distance between the primary conductors.
【０００７】又、振動等により一次導体の位置が移動す
るために、不平衡特性が部品によって変化するという問
題があった。又、一次導体を零相変流器の貫通孔の内部
に通す作業は、自動化が難しかった。[0007] In addition, there is a problem that the unbalance characteristic changes depending on parts because the position of the primary conductor moves due to vibration or the like. In addition, it is difficult to automate the operation of passing the primary conductor through the through-hole of the zero-phase current transformer.
【０００８】本発明の課題は、簡単な構造で一次導体を
固定でき、不平衡特性が不均一な個体差をなくし、一次
導体どうしの絶縁耐圧を向上させ、振動による不平衡特
性の変化と一次導体の位置ずれをなくし、回路基盤等へ
の実装を容易なものとし、基盤実装の自動化ができ、機
械強度も大きい零相変流器を提供することにある。SUMMARY OF THE INVENTION It is an object of the present invention to fix a primary conductor with a simple structure, eliminate individual differences in unbalance characteristics, improve the dielectric strength between primary conductors, change the unbalance characteristics due to vibration, and It is an object of the present invention to provide a zero-phase current transformer that eliminates positional displacement of conductors, facilitates mounting on a circuit board or the like, automates board mounting, and has high mechanical strength.
【０００９】[0009]
【課題を解決するための手段】本発明は、かかる問題を
解決するためになされたもので、ホルダーに一次導体の
本数と同数の保持穴を持つ前記トロイダルコイルの貫通
孔の内部を貫通する保持部を設け、該一次導体が前記保
持部の保持穴を通過し、該一次導体の端子及び前記トロ
イダルコイルの巻線の端子が端子台に固定されている零
相変流器を提供することによって目的を達成することが
できる。SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problem, and has a holder which penetrates a through-hole of the toroidal coil having the same number of holding holes as the number of primary conductors in a holder. By providing a zero-phase current transformer in which the primary conductor passes through the holding hole of the holding portion, and the terminal of the primary conductor and the terminal of the winding of the toroidal coil are fixed to a terminal block. The goal can be achieved.
【００１０】[0010]
【発明の実施の形態】前述のように、零相変流器の樹脂
製ホルダーが、一次導体の保持穴を持つ前記トロイダル
コイルの貫通孔の内部を貫通する保持部を持つことによ
り、トロイダルコイルの内部を貫通する一次導体の位置
が特定されるため、不平衡特性の個体差がなくなり、常
に良好な不平衡特性を得ることができる。又、前記保持
部が、絶縁性であり、前記保持部の保持穴の数が一次導
体の本数と同数であることから、複数の一次導体間の絶
縁、耐圧特性が向上し、又、振動等が印加しても、一次
導体の位置がずれることはない。更に、一次導体の端子
及び前記トロイダルコイルの巻線の端子が、端子台によ
って固定されているため、回路基盤等へ実装も容易とな
り、基盤実装の自動化を促進することが可能となる。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As described above, a resin holder for a zero-phase current transformer has a holding portion that penetrates the inside of a through hole of the toroidal coil having a holding hole for a primary conductor. Since the position of the primary conductor that penetrates the inside is specified, there is no individual difference in unbalance characteristics, and good unbalance characteristics can always be obtained. Further, since the holding portion is insulative and the number of holding holes of the holding portion is the same as the number of primary conductors, insulation between a plurality of primary conductors, pressure resistance characteristics are improved, vibration Does not shift the position of the primary conductor. Further, since the terminal of the primary conductor and the terminal of the winding of the toroidal coil are fixed by the terminal block, mounting on a circuit board or the like becomes easy, and automation of mounting the board can be promoted.
【００１１】[0011]
【実施例】以下、図面を用いて、本発明の実施例を説明
する。Embodiments of the present invention will be described below with reference to the drawings.
【００１２】本発明の一実施例の零相変流器の組立斜視
図を図１に示す。図２は、図１のホルダーを巻線の端子
通過穴方向から見た斜視図である。図３は、本発明の一
実施例による零相変流器を保持部方向から見た完成品の
斜視図である。FIG. 1 is an assembled perspective view of a zero-phase current transformer according to an embodiment of the present invention. FIG. 2 is a perspective view of the holder of FIG. 1 as viewed from a terminal passing hole direction of a winding. FIG. 3 is a perspective view of the completed product when the zero-phase current transformer according to one embodiment of the present invention is viewed from the direction of the holding portion.
【００１３】図１に示すように、本発明の零相変流器
は、高い比透磁率特性を有するパーマロイの環状の磁
心、又はフェライトコア等の環状の磁心１と、前記磁心
１に巻回した巻線２と、該巻線２を巻回した前記磁心１
の上下面に隣接する軟磁性材の板を環状に打ち抜いたシ
ールドリング３と、樹脂製のホルダー５ａと、端子台６
ａと、複数の一次導体７から構成される。As shown in FIG. 1, a zero-phase current transformer according to the present invention includes a permalloy annular magnetic core having a high relative magnetic permeability characteristic, or an annular magnetic core 1 such as a ferrite core, and a coil wound around the magnetic core 1. And the magnetic core 1 around which the winding 2 is wound.
Ring 3, a resin-made holder 5a, and a terminal block 6
a and a plurality of primary conductors 7.
【００１４】樹脂製のホルダー５ａは、前記磁心１の巻
線２を巻回したトロイダルコイルと、前記シールドリン
グ３の貫通孔１６の内部を通過し、一次導体７の本数と
同数の保持穴１０を持つ保持部１１を有する。A holder 5a made of resin is provided with a toroidal coil around which the winding 2 of the magnetic core 1 is wound and a holding hole 10 having the same number as the number of the primary conductors 7 passing through the inside of the through hole 16 of the shield ring 3. And a holding unit 11 having
【００１５】本発明の零相変流器は、前記樹脂製のホル
ダー５ａに、前記磁心１に巻線２を巻回したトロイダル
コイルと、前記シールドリング３を収納し、前記巻線２
の端子８を図２に示す背面の巻線の端子の通過穴９及び
巻線の通過溝４を通し、成形樹脂１２（図３参照）を流
し固定する。In the zero-phase current transformer of the present invention, the toroidal coil in which the winding 2 is wound around the magnetic core 1 and the shield ring 3 are housed in the resin holder 5a.
The terminal 8 is passed through the through-hole 9 of the terminal of the winding on the back side shown in FIG. 2 and the passage groove 4 of the winding, and the molding resin 12 (see FIG. 3) is poured and fixed.
【００１６】図２及び図３に示すように、前記成形樹脂
１２の硬化後、前記保持部１１の保持穴１０及び前記樹
脂製のホルダー５ａの一次導体の通過溝１７に一次導体
７を填装し、前記樹脂製のホルダー５ａに、前記端子台
６ａを接続し、一次導体７の端子１３を前記端子台６ａ
の一次導体端子固定部１４に嵌装し、前記巻線の端子８
を前記端子台６ａの巻線端子固定部１５に固定し、本発
明の零相変流器が完成する。As shown in FIGS. 2 and 3, after the molding resin 12 is cured, the primary conductor 7 is loaded into the holding hole 10 of the holding portion 11 and the passage 17 of the primary conductor of the resin holder 5a. Then, the terminal block 6a is connected to the resin holder 5a, and the terminal 13 of the primary conductor 7 is connected to the terminal block 6a.
And the terminal 8 of the winding
Is fixed to the winding terminal fixing portion 15 of the terminal block 6a to complete the zero-phase current transformer of the present invention.
【００１７】巻線の端子の通過穴方向から見た本発明の
零相変流器の完成品を図４に示す。FIG. 4 shows a completed zero-phase current transformer according to the present invention as viewed from the direction of the passage hole of the terminal of the winding.
【００１８】前述したように、本発明による零相変流器
は、保持部１１の保持穴１０によって、一次導体７を保
持することにより、不平衡特性の個体差、即ち、特性ば
らつきはなくなる。As described above, in the zero-phase current transformer according to the present invention, since the primary conductor 7 is held by the holding holes 10 of the holding portion 11, individual differences in unbalanced characteristics, that is, characteristic variations are eliminated.
【００１９】又、保持穴１０の数が、一次導体７の本数
と同数であり、かつ、保持部１１が絶縁性であるため、
複数の一次導体どうしの絶縁耐圧が向上し、振動等が生
じても、一次導体の位置がずれることはない。Since the number of the holding holes 10 is the same as the number of the primary conductors 7 and the holding portion 11 is insulative,
Even if the withstand voltage between the plurality of primary conductors is improved and vibration or the like occurs, the position of the primary conductor does not shift.
【００２０】又、一次導体７が保持部１１の保持穴１０
によって保持され、かつ、一次導体７の端子１３が端子
台６ａに固定されていることから、回路基盤等への自動
搭載も可能である。The primary conductor 7 is provided in the holding hole 10 of the holding portion 11.
And the terminal 13 of the primary conductor 7 is fixed to the terminal block 6a, so that it can be automatically mounted on a circuit board or the like.
【００２１】又、本発明の零相変流器は、回路基盤上に
一次導体７の端子１３と巻線の端子８によって固定され
るため、一次導体７の数が少なくとも２本あり、かつ、
前記磁心１に巻回する巻線が１本あることから、少なく
とも６つの端子によって固定することになり、零相変流
器の回路基盤との機械的強度も強くなる。The zero-phase current transformer of the present invention is fixed on the circuit board by the terminal 13 of the primary conductor 7 and the terminal 8 of the winding, so that the number of the primary conductors 7 is at least two, and
Since there is one winding wound around the magnetic core 1, it is fixed by at least six terminals, and the mechanical strength of the zero-phase current transformer with the circuit board is also increased.
【００２２】本実施例は、２相（単相）回路に使用され
る零相変流器を説明したが、３相回路にも、本発明の適
用は可能である。In this embodiment, the zero-phase current transformer used in a two-phase (single-phase) circuit has been described. However, the present invention can be applied to a three-phase circuit.
【００２３】[0023]
【発明の効果】本発明によれば、簡単な構造で一次導体
を一定の場所に固定することができ、トロイダルコイル
の貫通孔の内部での遊びをなくすことによって、不平衡
特性の個体差をなくし、一次導体どうしの絶縁耐圧を向
上し、振動による一次導体の位置ずれをなくすことがで
きる。一次導体の端子及び前記トロイダルコイルの巻線
の端子が端子台によって固定されているため、回路基盤
等への実装を容易なものとし、基盤実装の自動化を促進
する。更に、少なくとも６つの端子によって固定するこ
とになり、零相変流器の回路基盤との機械的強度も強く
なる。According to the present invention, the primary conductor can be fixed at a fixed place with a simple structure, and by eliminating play inside the through hole of the toroidal coil, individual differences in unbalance characteristics can be reduced. It is possible to improve the withstand voltage between the primary conductors and eliminate the displacement of the primary conductor due to vibration. Since the terminal of the primary conductor and the terminal of the winding of the toroidal coil are fixed by the terminal block, mounting on a circuit board or the like is facilitated, and automation of mounting the board is promoted. Furthermore, since it is fixed by at least six terminals, the mechanical strength of the zero-phase current transformer with the circuit board is increased.
【図１】本発明の一実施例による零相変流器の組立斜視
図。FIG. 1 is an assembled perspective view of a zero-phase current transformer according to an embodiment of the present invention.
【図２】図１のホルダーを巻線の端子通過穴方向から見
た斜視図。FIG. 2 is a perspective view of the holder of FIG. 1 as viewed from a terminal passing hole direction of a winding;
【図３】本発明の一実施例による零相変流器を保持部方
向から見た完成品の斜視図。FIG. 3 is a perspective view of a completed product when the zero-phase current transformer according to one embodiment of the present invention is viewed from the direction of a holding unit.
【図４】本発明の一実施例による零相変流器を巻線の端
子の通過穴方向から見た完成品の斜視図。FIG. 4 is a perspective view of a finished product of the zero-phase current transformer according to one embodiment of the present invention, as viewed from a direction of a through hole of a terminal of a winding.
【図５】従来技術による零相変流器を示す斜視図。FIG. 5 is a perspective view showing a zero-phase current transformer according to the related art.
１ 磁心 ２ 巻線 ３ シールドリング ４ 通過溝 ５，５ａ ホルダー ６，６ａ 端子台 ７ 一次導体 ８，１３ 端子 ９ 通過穴 １０ 保持穴 １１ 保持部 １２ 成形樹脂 １４ 一次導体端子固定部 １５ 巻線端子固定部 １６ 貫通孔 １７ 通過溝 DESCRIPTION OF SYMBOLS 1 Magnetic core 2 Winding 3 Shield ring 4 Passing groove 5, 5a Holder 6, 6a Terminal block 7 Primary conductor 8, 13 Terminal 9 Passing hole 10 Holding hole 11 Holding part 12 Molding resin 14 Primary conductor terminal fixing part 15 Winding terminal fixing Part 16 through hole 17 passage groove
Claims (1)
ロイダルコイルと、軟磁性材の板を環状に打ち抜いたシ
ールドリングと、前記トロイダルコイルと前記シールド
リングを収納するホルダーを組み合わせてなる零相変流
器において、該ホルダーに一次導体の本数と同数の保持
穴を持ち前記トロイダルコイルの貫通孔の内部を貫通す
る保持部を設け、該一次導体が前記保持部の保持穴を通
過し、該一次導体の端子及び前記トロイダルコイルの巻
線の端子が端子台に固定されていることを特徴とする零
相変流器。1. A combination of a toroidal coil uniformly wound around the entire circumference of an annular magnetic core, a shield ring formed by punching a sheet of soft magnetic material in an annular shape, and a holder for accommodating the toroidal coil and the shield ring. In the zero-phase current transformer, the holder is provided with a holding portion having the same number of holding holes as the number of primary conductors and penetrating inside the through hole of the toroidal coil, and the primary conductor passes through the holding hole of the holding portion. The terminal of the primary conductor and the terminal of the winding of the toroidal coil are fixed to a terminal block.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8188384A JPH1022149A (en) | 1996-06-28 | 1996-06-28 | Zero-phase current transformer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8188384A JPH1022149A (en) | 1996-06-28 | 1996-06-28 | Zero-phase current transformer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH1022149A true JPH1022149A (en) | 1998-01-23 |
Family
ID=16222689
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8188384A Pending JPH1022149A (en) | 1996-06-28 | 1996-06-28 | Zero-phase current transformer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH1022149A (en) |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2802016A1 (en) * | 1999-12-06 | 2001-06-08 | Gen Electric | Current transformer with correction of asymmetries, for use in earth leakage relays, uses magnetic probes to detect asymmetries, and removal of material or addition of magnetic paint to correct them |
| JP2003234224A (en) * | 2002-02-06 | 2003-08-22 | Mitsubishi Electric Corp | Method of arranging conductor with respect to zero- phase current transformer and holding and position adjusting device |
| JP2005101640A (en) * | 2004-11-12 | 2005-04-14 | Mitsubishi Electric Corp | Transformer and its manufacturing method |
| JP2007142065A (en) * | 2005-11-17 | 2007-06-07 | Sht Corp Ltd | Zero-phase current transformer |
| US7430157B2 (en) | 2003-12-18 | 2008-09-30 | Sony Corporation | Recording device, recording method, reproducing device, and reproducing method |
| GB2455847A (en) * | 2007-12-19 | 2009-06-24 | Atreus Entpr Ltd | A current transformer using magnetic elements to improve the core balance |
| EP2423693A1 (en) * | 2010-08-24 | 2012-02-29 | Liaisons Electroniques-Mecaniques Lem S.A. | Toroidal fluxgate current transducer |
| JP2012112947A (en) * | 2010-11-24 | 2012-06-14 | General Electric Co <Ge> | Magnetic shield for current transformer in electronic watt-hour meter |
| JP2013160638A (en) * | 2012-02-06 | 2013-08-19 | Nippon Soken Inc | Current detector |
| JP2014075974A (en) * | 2013-12-20 | 2014-04-24 | Panasonic Corp | Power supply control device |
| WO2020202653A1 (en) * | 2019-04-04 | 2020-10-08 | 三菱電機株式会社 | Earth leakage circuit breaker |
-
1996
- 1996-06-28 JP JP8188384A patent/JPH1022149A/en active Pending
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2802016A1 (en) * | 1999-12-06 | 2001-06-08 | Gen Electric | Current transformer with correction of asymmetries, for use in earth leakage relays, uses magnetic probes to detect asymmetries, and removal of material or addition of magnetic paint to correct them |
| JP2003234224A (en) * | 2002-02-06 | 2003-08-22 | Mitsubishi Electric Corp | Method of arranging conductor with respect to zero- phase current transformer and holding and position adjusting device |
| US7430157B2 (en) | 2003-12-18 | 2008-09-30 | Sony Corporation | Recording device, recording method, reproducing device, and reproducing method |
| JP2005101640A (en) * | 2004-11-12 | 2005-04-14 | Mitsubishi Electric Corp | Transformer and its manufacturing method |
| JP2007142065A (en) * | 2005-11-17 | 2007-06-07 | Sht Corp Ltd | Zero-phase current transformer |
| GB2455847B (en) * | 2007-12-19 | 2010-03-10 | Atreus Entpr Ltd | A curent transformer |
| GB2455847A (en) * | 2007-12-19 | 2009-06-24 | Atreus Entpr Ltd | A current transformer using magnetic elements to improve the core balance |
| EP2423693A1 (en) * | 2010-08-24 | 2012-02-29 | Liaisons Electroniques-Mecaniques Lem S.A. | Toroidal fluxgate current transducer |
| JP2012112947A (en) * | 2010-11-24 | 2012-06-14 | General Electric Co <Ge> | Magnetic shield for current transformer in electronic watt-hour meter |
| JP2013160638A (en) * | 2012-02-06 | 2013-08-19 | Nippon Soken Inc | Current detector |
| JP2014075974A (en) * | 2013-12-20 | 2014-04-24 | Panasonic Corp | Power supply control device |
| WO2020202653A1 (en) * | 2019-04-04 | 2020-10-08 | 三菱電機株式会社 | Earth leakage circuit breaker |
| JP6811906B1 (en) * | 2019-04-04 | 2021-01-13 | 三菱電機株式会社 | Earth leakage breaker |
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