JPH02287266A - Dc current measuring apparatus - Google Patents
Dc current measuring apparatusInfo
- Publication number
- JPH02287266A JPH02287266A JP1107690A JP10769089A JPH02287266A JP H02287266 A JPH02287266 A JP H02287266A JP 1107690 A JP1107690 A JP 1107690A JP 10769089 A JP10769089 A JP 10769089A JP H02287266 A JPH02287266 A JP H02287266A
- Authority
- JP
- Japan
- Prior art keywords
- core
- current
- coil
- time
- capacitor
- 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.)
- Granted
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R15/00—Details of measuring arrangements of the types provided for in groups G01R17/00 - G01R29/00, G01R33/00 - G01R33/26 or G01R35/00
- G01R15/14—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks
- G01R15/18—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using inductive devices, e.g. transformers
- G01R15/183—Adaptations providing voltage or current isolation, e.g. for high-voltage or high-current networks using inductive devices, e.g. transformers using transformers with a magnetic core
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Transformers For Measuring Instruments (AREA)
- Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
- Measurement Of Current Or Voltage (AREA)
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
この発明は、例えば加速器の直流電流を測定する装置に
関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a device for measuring direct current of, for example, an accelerator.
［従来の技術］
第２図は、例えば雑誌ザ・シックスス・シンプ・オン・
アクセレレータ・サイエンス・アンドテクノロジー（Ｔ
ｈｅ ６ｔｈ Ｓｙｍｐ、ｏｎ Ａｃｃｅｌｅｒａｔｏ
ｒＳｃｉｅｎｃｅ ａｎｄ Ｔｅｃｈｎｏｌｏｇｙ）″
（１９８７年）第２１６ページに記載の従来の直流電流
測定装置を示す回路図である１図において、（１）は例
えば加速器（図示しない）から荷電粒子の直流電流の向
きを示している。（２）は高透磁率の複数個のドーナツ
状コア、（３）は各コア（２）に巻がれて高周波電流を
コア（２）に流すコイル、（４）はこれらコイル（３）
の両端間に接続されて例えば周波数ｆの高周波電流を供
給する高周波電源である。なお、この高周波電源（４）
には直流カット用のコンデンサおよび抵抗が図示のよう
に直列に接続されている。（５）は各コア（２）に巻か
れてコア（２）内の磁束の変化を測定するピックアップ
コイル、（６）はこれらピックアップコイル（５）の両
端間に接続されてピックアップコイル（５）でピックア
ップされた高周波の第２高周波と高周波電源（４）から
導出されて例えば２ｆの周波数を有する基準信号との位
相差を検出するための位相差測定器例えばロックイン増
幅器、（７）はこのロックイン増幅器（６）の出力側に
接続されて直流電流（１）とは反対の方向に電流を流す
打消しコイルである。[Prior art] Fig. 2 shows, for example, the magazine The Sixth Simp on.
Accelerator Science and Technology (T
he 6th Symp, on Accelerato
rScience and Technology)
(1987), page 216, which is a circuit diagram showing a conventional DC current measurement device, (1) indicates the direction of DC current of charged particles from, for example, an accelerator (not shown). (2) is a plurality of donut-shaped cores with high magnetic permeability, (3) is a coil that is wound around each core (2) and causes a high frequency current to flow through the core (2), and (4) is these coils (3).
A high frequency power source is connected between both ends of the power source and supplies a high frequency current having a frequency f, for example. In addition, this high frequency power supply (4)
A capacitor and a resistor for DC cut are connected in series as shown in the figure. (5) is a pickup coil that is wound around each core (2) to measure changes in magnetic flux within the core (2); (6) is a pickup coil (5) that is connected between both ends of these pickup coils (5); A phase difference measuring device, such as a lock-in amplifier (7), for detecting the phase difference between the second high frequency wave picked up by the high frequency power source (4) and a reference signal having a frequency of, for example, 2f, derived from the high frequency power source (4). This is a cancellation coil that is connected to the output side of the lock-in amplifier (6) and causes current to flow in the opposite direction to the direct current (1).
従来の直流電流測定装置は上述したように構成されてお
り、高周波電源（４）によってコイルく３）にはコア（
２）が飽和するのに十分な電流が流される。しかし、コ
イル（３）の電流（交流）が小さい場合にはコアく２）
が飽和していないので、コイル（３）に流れる電流に比
例した磁束がコア（２）内に発生する。コイル電流が大
きくなってコア（２）が飽和してしまうと、コア（２）
内の磁束は一定値になってしまう。ピックアップコイル
（５）の出力は、コア（２）内の磁束の時間変化に比例
する。よって、出力はコア（２）が飽和していない場合
にのみ電圧を出すパルス状となる。このパルス電圧は、
高周波の基本波および奇数次高周波成分からなっている
。こここで、コア（２）を鎖交するように荷電粒子の直
流電流（１）が流れた場合、コイル（３）の高周波電流
にバイアスがかかった状態になる。この時の出力はパル
ス状ではあるが、偶数次高周波成分も含むようになる。The conventional DC current measuring device is configured as described above, and the core (3) is connected to the coil (3) by the high frequency power supply (4).
A sufficient current is applied to saturate 2). However, if the current (alternating current) in the coil (3) is small, the coil (2)
is not saturated, a magnetic flux proportional to the current flowing through the coil (3) is generated within the core (2). When the coil current becomes large and the core (2) becomes saturated, the core (2)
The magnetic flux inside becomes a constant value. The output of the pickup coil (5) is proportional to the time change of the magnetic flux within the core (2). Therefore, the output is in the form of a pulse that outputs voltage only when the core (2) is not saturated. This pulse voltage is
It consists of a high-frequency fundamental wave and odd-numbered high-frequency components. Here, when the DC current (1) of charged particles flows so as to interlink with the core (2), a bias is applied to the high frequency current of the coil (3). Although the output at this time is pulse-like, it also includes even-order high-frequency components.
この偶数次高周波成分をロックイン増幅器（６）で検出
すると、第２高周波成分の電圧を検出することができる
。この電圧に比例した電流をコア（２）に直流電流（１
）とは逆向きにコイル（７）に流して第２高周波成分を
０にするようにしたとする。この時打消しコイル（７）
に流れる電流値は直流電流（１）すなわち荷電粒子の電
流値に等しい。なお、コア（２）に高周波電流を流すコ
イルを２個で逆向きにしかつピツコア・ンプコイル（５
）を同方向に巻いているのは基本波および奇数次高周波
成分を打消すためである。When this even numbered high frequency component is detected by the lock-in amplifier (6), the voltage of the second high frequency component can be detected. A current proportional to this voltage is applied to the core (2) with a direct current (1
) is applied to the coil (7) in the opposite direction to reduce the second high frequency component to 0. At this time, the cancellation coil (7)
The current value flowing through is equal to the DC current (1), that is, the current value of the charged particles. In addition, the two coils that flow high-frequency current to the core (2) are arranged in opposite directions, and the Pitz core amplifier coil (5
) are wound in the same direction to cancel out the fundamental wave and odd-numbered high frequency components.
［発明が解決しようとする課題］
従来の直流電流測定装置では、コアが飽和するのに十分
な高周波電流を流すためには大きな高周波電源が必要だ
った。また、コアのヒステリシス損失などによるコアの
発熱が問題となっていたにの発明は、上述したような問
題点を解決するためになされたもので、高周波電源を小
型化でき、さらに測定感度を良くした直流電流測定装置
を得ることを目的とする。[Problems to be Solved by the Invention] Conventional DC current measurement devices require a large high-frequency power source to flow enough high-frequency current to saturate the core. In addition, the invention was made in order to solve the problem of core heat generation due to core hysteresis loss, etc., and was made to reduce the size of the high-frequency power supply and further improve measurement sensitivity. The purpose of the present invention is to obtain a direct current measuring device with
［課題を解決するための手段〕
この発明に係る直流電流測定装置は、コアに巻かれたコ
イルに回路接続された共振用コンデンサと、このコンデ
ンサと直列に接続された電流測定用抵抗と、これら抵抗
、コンデンサおよびコイルから成る回路の両端間に接続
され、コイルとコンデンサの共振状態で高周波電源を供
給する高周波電源と、抵抗の両端間に接続されて基準信
号に対する高周波の位相差を検出する位相差測定器とを
備えたものである。[Means for Solving the Problems] A direct current measuring device according to the present invention includes a resonant capacitor connected in a circuit to a coil wound around a core, a current measuring resistor connected in series with the capacitor, and a current measuring resistor connected in series with the capacitor. A high-frequency power supply is connected between both ends of a circuit consisting of a resistor, a capacitor, and a coil, and supplies high-frequency power when the coil and capacitor resonate, and a high-frequency power supply is connected between both ends of the resistor and detects the phase difference of the high frequency with respect to the reference signal. It is equipped with a phase difference measuring device.
［作 用］
この発明においては、コイルとコンデンサの共振状態で
高周波電源を動作させ、コンデンサと直列に接続されて
いる抵抗に流れる高周波電流をモニタすることによりコ
アと鎖交する直流電流を感度良く測定することができる
。[Function] In this invention, the high-frequency power supply is operated in a state where the coil and the capacitor resonate, and the high-frequency current flowing through the resistor connected in series with the capacitor is monitored, thereby detecting the direct current interlinking with the core with high sensitivity. can be measured.
［実施例］
第１図はこの発明の直流電流測定装置による一実施例を
示す回路図である。第１図において、（８）はコア（２
）に巻かれたコイル（３）に回路接続、例えば図示のよ
うに直列に接続された共振用コンデンサ、（９）はこの
コンデンサ（８）と直列に接続された電流測定用抵抗、
（４＾）はこれら抵抗（９）、コンデンサ（８）および
コイル（３）から成る直列回路の両端間に接続され、コ
イル（３）とコンデンサ（８）の共振状態で高周波電流
をコイル（３）に供給する小型の高周波電源、そして（
６）は抵抗（９）の両端間に接続された位相差測定器例
えばロックイン増幅器である。[Embodiment] FIG. 1 is a circuit diagram showing an embodiment of the DC current measuring device of the present invention. In Figure 1, (8) is the core (2
), the circuit is connected to the coil (3), for example, a resonant capacitor connected in series as shown, (9) is a current measuring resistor connected in series with this capacitor (8),
(4^) is connected across the series circuit consisting of the resistor (9), capacitor (8) and coil (3), and transmits a high frequency current to the coil (3) when the coil (3) and capacitor (8) resonate. ), and (
6) is a phase difference measuring device, such as a lock-in amplifier, connected across the resistor (9).
上述したように構成されたこの発明の直流電流測定装置
では、コイル（３）のインダクタンスとコンデンサ（８
）のキャパシタンスとからもとまる共振周波数ｆ。付近
で高周波電源（４＾）を動作させるとする。この場合、
電源容量は小さくても共振状態になっているために大電
流をコア（２）に流すことができる。コア（２）が飽和
した場合、コア（２）の比透磁率は急激に下がるために
コア（２）のインピーダンスがほとんど０になる。この
とき、さらにパルス状の大電流が回路に流れることにな
る。この状態でコア（２）に鎖交するように荷電粒子の
直流電流が流れた場合、従来例と同様にコイル（３）に
バイアス電流が流れた状態になる。この時、コア（２）
の飽和する時間が多少異なってくるために、パルス状の
大電流が発生する時間も変化することになる。この時間
の、周波数２ｆ、の基準信号に対するずれをロックイン
増幅器（６）で測定すればコア（２）に鎖交して流れる
電流値を測定することができる。パルス状の大電流のシ
フトであるために位相検出は非常に簡便となり、また非
常に感度もよくなる。In the direct current measuring device of the present invention configured as described above, the inductance of the coil (3) and the capacitor (8
) and the resonant frequency f. Suppose that a high frequency power supply (4^) is operated nearby. in this case,
Even though the power supply capacity is small, a large current can flow through the core (2) because it is in a resonant state. When the core (2) is saturated, the relative magnetic permeability of the core (2) rapidly decreases, so that the impedance of the core (2) becomes almost zero. At this time, a large pulsed current flows through the circuit. In this state, when a DC current of charged particles flows interlinking with the core (2), a bias current flows through the coil (3) as in the conventional example. At this time, core (2)
Since the time for saturation of the current varies somewhat, the time for generating a large pulsed current also varies. By measuring the deviation of this time with respect to the reference signal of frequency 2f using the lock-in amplifier (6), it is possible to measure the value of the current flowing interlinked with the core (2). Since it is a pulse-like shift of a large current, phase detection is very simple, and the sensitivity is also very high.
なお、上述した実施例では、ロックイン増幅器で第２高
周波成分の、基準信号に対する位相差を測定していたが
、偶数次高周波の測定であれば同様の効果が期待できる
。また、ロックイン増幅器を用いなくても位相差を検出
できるものなら、どんなものでも同様の効果が期待でき
る。更に、第２図の打消しコイル（７）のような負帰還
を加えても同様の動作を期待できる６また、コンデンサ
をコイルとに直列に接続していたが、並列に接続しても
同様の効果が期待できる。コアを２個以上用いても同様
の効果が期待できる。In the above embodiment, the lock-in amplifier measures the phase difference of the second high frequency component with respect to the reference signal, but similar effects can be expected if even-order high frequencies are measured. Further, similar effects can be expected with any device that can detect a phase difference without using a lock-in amplifier. Furthermore, the same behavior can be expected even if a negative feedback like the cancellation coil (7) in Figure 2 is added.6Also, although the capacitor was connected in series with the coil, the same effect can be obtained even if the capacitor is connected in parallel. The effects can be expected. Similar effects can be expected even if two or more cores are used.
［発明の効果］
以上のように、この発明は、コアに巻かれたコイルに回
路接続された共振用コンデンサと、このコンデンサと直
列に接続された電流測定用抵抗と、これら抵抗、コンデ
ンサおよびコイルから成る回路の両端間に接続され、コ
イルとコンデンサの共振状態で高周波電流を供給する高
周波電源と、抵抗の両端間に接続されて基準信号に対す
る高周波の位相差を検出する位相差測定器とを設け、コ
イルとコンデンサの共振状態を利用して荷電粒子の電流
値を測定することにより、精度および感度の良い測定が
容易に可能となる効果を奏する。[Effects of the Invention] As described above, the present invention provides a resonant capacitor circuit-connected to a coil wound around a core, a current measuring resistor connected in series with this capacitor, and a combination of these resistors, capacitors, and coils. A high-frequency power supply is connected between both ends of a circuit that supplies a high-frequency current in a state where the coil and capacitor resonate, and a phase difference measuring device is connected between both ends of a resistor and detects the high-frequency phase difference with respect to a reference signal. By using the resonant state of the coil and the capacitor to measure the current value of the charged particles, it is possible to easily perform measurements with high accuracy and sensitivity.
第１図はこの発明の一実施例を示す回路図、そして第２
図は従来の直流電流測定装置を示す回路図である。
図において、（１）は荷電粒子の直流電流、（２）はコ
ア、（３）はコイル、（４＾）は高周波電源、（６）は
ロックイン増幅器。
ち１図
代 理 人
曾
我
道
照FIG. 1 is a circuit diagram showing one embodiment of the present invention, and FIG.
The figure is a circuit diagram showing a conventional DC current measuring device. In the figure, (1) is the DC current of charged particles, (2) is the core, (3) is the coil, (4^) is the high frequency power supply, and (6) is the lock-in amplifier. Chi 1 Illustration Osamu Michihito Soga
Claims (1)
巻かれて高周波電流を前記コアに流すコイルと、このコ
イルに回路接続された共振用コンデンサと、このコンデ
ンサと直列に接続された電流測定用抵抗と、これら抵抗
、コンデンサおよびコイルから成る回路の両端間に接続
され、前記コイルと前記コンデンサの共振状態で前記高
周波電流を供給する高周波電源と、前記抵抗の両端間に
接続されて基準信号に対する高周波の位相差を検出する
位相差測定器とを備え、前記コアと鎖交する直流電流を
測定することを特徴とする直流電流測定装置。(1) At least one donut-shaped core, a coil wound around this core to flow a high-frequency current to the core, a resonance capacitor connected in circuit to this coil, and a current measurement device connected in series with this capacitor. a high-frequency power source connected between both ends of a circuit consisting of these resistors, a capacitor, and a coil to supply the high-frequency current when the coil and the capacitor resonate, and a high-frequency power source connected between both ends of the resistor to generate a reference signal. A direct current measuring device comprising: a phase difference measuring device for detecting a phase difference of a high frequency wave with respect to the core, and measuring a direct current interlinking with the core.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1107690A JP2816175B2 (en) | 1989-04-28 | 1989-04-28 | DC current measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1107690A JP2816175B2 (en) | 1989-04-28 | 1989-04-28 | DC current measuring device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02287266A true JPH02287266A (en) | 1990-11-27 |
| JP2816175B2 JP2816175B2 (en) | 1998-10-27 |
Family
ID=14465495
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1107690A Expired - Fee Related JP2816175B2 (en) | 1989-04-28 | 1989-04-28 | DC current measuring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2816175B2 (en) |
Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6316931B1 (en) | 1998-12-15 | 2001-11-13 | Tdk Corporation | Magnetic sensor apparatus and current sensor apparatus |
| FR2919068A1 (en) * | 2007-07-19 | 2009-01-23 | Airbus France Sa | PERFECTED CURRENT SENSOR |
| WO2012038478A1 (en) * | 2010-09-21 | 2012-03-29 | Shakira Limited | Dc & ac current detection circuit |
| JP2012526981A (en) * | 2009-05-11 | 2012-11-01 | リエゾン、エレクトロニク−メカニク、エルウエム、ソシエテ、アノニム | Closed loop fluxgate current sensor |
| US8361731B2 (en) | 2007-07-19 | 2013-01-29 | Biomerieux | Ezrin assay method for the in vitro diagnosis of colorectal cancer |
| US8367362B2 (en) | 2007-07-19 | 2013-02-05 | Biomerieux | Aminoacylase 1 assay method for the in vitro diagnosis of colorectal cancer |
| US8445211B2 (en) | 2007-07-19 | 2013-05-21 | Biomerieux | I-Plastin assay method for the in vitro diagnosis of colorectal cancer |
| US8735078B2 (en) | 2007-07-19 | 2014-05-27 | Biomerieux | Apolipoprotein AII assay method for the in vitro diagnosis of colorectal cancer |
| JP2017058288A (en) * | 2015-09-17 | 2017-03-23 | 株式会社中央製作所 | Non-contact dc current sensor and dc current measuring system using non-contact dc current sensor |
| US9726670B2 (en) | 2007-07-19 | 2017-08-08 | Biomerieux | Method for the assay of liver fatty acid binding protein, ACE and CA 19-9 for the in vitro diagnosis of colorectal cancer |
| US9891223B2 (en) | 2007-07-19 | 2018-02-13 | Biomerieux | Method of assaying leukocyte elastase inhibitor for the in vitro diagnosis of colorectal cancer |
| US10591482B2 (en) | 2007-07-19 | 2020-03-17 | Biomerieux | Method of assaying Apolipoprotein AI for the in vitro diagnosis of colorectal cancer |
| WO2024180751A1 (en) * | 2023-03-02 | 2024-09-06 | スミダコーポレーション株式会社 | Current sensor circuit |
-
1989
- 1989-04-28 JP JP1107690A patent/JP2816175B2/en not_active Expired - Fee Related
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6316931B1 (en) | 1998-12-15 | 2001-11-13 | Tdk Corporation | Magnetic sensor apparatus and current sensor apparatus |
| US9726670B2 (en) | 2007-07-19 | 2017-08-08 | Biomerieux | Method for the assay of liver fatty acid binding protein, ACE and CA 19-9 for the in vitro diagnosis of colorectal cancer |
| US8735078B2 (en) | 2007-07-19 | 2014-05-27 | Biomerieux | Apolipoprotein AII assay method for the in vitro diagnosis of colorectal cancer |
| US10591482B2 (en) | 2007-07-19 | 2020-03-17 | Biomerieux | Method of assaying Apolipoprotein AI for the in vitro diagnosis of colorectal cancer |
| US9891223B2 (en) | 2007-07-19 | 2018-02-13 | Biomerieux | Method of assaying leukocyte elastase inhibitor for the in vitro diagnosis of colorectal cancer |
| US8361731B2 (en) | 2007-07-19 | 2013-01-29 | Biomerieux | Ezrin assay method for the in vitro diagnosis of colorectal cancer |
| US8367362B2 (en) | 2007-07-19 | 2013-02-05 | Biomerieux | Aminoacylase 1 assay method for the in vitro diagnosis of colorectal cancer |
| WO2009024692A1 (en) * | 2007-07-19 | 2009-02-26 | Airbus France | Improved current sensor |
| FR2919068A1 (en) * | 2007-07-19 | 2009-01-23 | Airbus France Sa | PERFECTED CURRENT SENSOR |
| US8445211B2 (en) | 2007-07-19 | 2013-05-21 | Biomerieux | I-Plastin assay method for the in vitro diagnosis of colorectal cancer |
| US8773112B2 (en) | 2007-07-19 | 2014-07-08 | Airbus Operations Sas | Current sensor |
| JP2012526981A (en) * | 2009-05-11 | 2012-11-01 | リエゾン、エレクトロニク−メカニク、エルウエム、ソシエテ、アノニム | Closed loop fluxgate current sensor |
| US8975890B2 (en) | 2010-09-21 | 2015-03-10 | Shakira Limited | DC and AC current detection circuit |
| WO2012038478A1 (en) * | 2010-09-21 | 2012-03-29 | Shakira Limited | Dc & ac current detection circuit |
| JP2017058288A (en) * | 2015-09-17 | 2017-03-23 | 株式会社中央製作所 | Non-contact dc current sensor and dc current measuring system using non-contact dc current sensor |
| WO2024180751A1 (en) * | 2023-03-02 | 2024-09-06 | スミダコーポレーション株式会社 | Current sensor circuit |
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|---|---|
| JP2816175B2 (en) | 1998-10-27 |
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