JP2002022814A - Magnetism measuring device - Google Patents
Magnetism measuring deviceInfo
- Publication number
- JP2002022814A JP2002022814A JP2000201861A JP2000201861A JP2002022814A JP 2002022814 A JP2002022814 A JP 2002022814A JP 2000201861 A JP2000201861 A JP 2000201861A JP 2000201861 A JP2000201861 A JP 2000201861A JP 2002022814 A JP2002022814 A JP 2002022814A
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- JP
- Japan
- Prior art keywords
- magnetic
- calibration
- measuring
- signal
- current source
- 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
Landscapes
- Measuring Magnetic Variables (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、複数のフラックス
ゲート型等の磁気センサを用いた磁気測定器に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetometer using a plurality of fluxgate type magnetic sensors.
【０００２】[0002]
【従来の技術】従来、任意の位置で様々な方向の磁界を
測定する磁気測定器として、図４に示すような自由に移
動させることが可能な２つの磁気センサ１４、１５をケ
ーブル１６、１７を介して測定回路部品を組み込んだ電
子回路ユニット１８に接続した磁気測定器が用いられて
いる。図５は２つの磁気センサ１４、１５の配置例を示
したものであるが、同図（ａ）は磁気センサ１４、１５
間を比較的離して配置した例であり、磁気勾配の測定に
よく用いられるものである。また、同図（ｂ）は磁気セ
ンサ１４、１５間を接近して配置した例であり、全磁気
測定や直交３方向成分測定に用いられる。実際の測定に
おいては、測定毎の目的に対応して最適な状態に磁気セ
ンサを近づけて使用されている。2. Description of the Related Art Conventionally, as a magnetic measuring device for measuring magnetic fields in various directions at arbitrary positions, two magnetic sensors 14 and 15 which can be freely moved as shown in FIG. A magnetic measuring device connected to an electronic circuit unit 18 incorporating a measuring circuit component through the interface is used. FIG. 5 shows an example of the arrangement of the two magnetic sensors 14 and 15, and FIG.
This is an example in which they are arranged relatively far apart, and is often used for measuring a magnetic gradient. FIG. 2B shows an example in which the magnetic sensors 14 and 15 are arranged close to each other, and is used for all-magnetic measurement and orthogonal three-direction component measurement. In actual measurement, the magnetic sensor is used with the magnetic sensor approaching an optimal state corresponding to the purpose of each measurement.
【０００３】[0003]
【発明が解決しようとする課題】従来の磁気測定器は上
記のように構成されているが、２つの磁気センサを図５
（ｂ）のように近ずけて配置した場合、磁気センサ同志
の相互干渉によって磁気センサの測定感度が変化する。
この測定感度の変化量は２つの磁気センサの相対位置に
より変化するため、従来の磁気測定器では磁気センサ間
の距離を固定して用いたり、測定感度変化を無視して使
用していたため相対位置によっては正確な磁界測定が行
えないという問題がある。本発明は、このような事情に
鑑みてなされたものであり、磁気センサの測定感度の変
化を容易に補正することができる磁気測定器を提供する
ことを目的とする。The conventional magnetometer is constructed as described above.
When the sensors are arranged close to each other as shown in FIG. 3B, the measurement sensitivity of the magnetic sensors changes due to mutual interference between the magnetic sensors.
Since the amount of change in the measurement sensitivity changes depending on the relative position of the two magnetic sensors, the conventional magnetic measurement device uses a fixed distance between the magnetic sensors, or ignores the change in the measurement sensitivity and uses the relative position. In some cases, there is a problem that accurate magnetic field measurement cannot be performed. The present invention has been made in view of such circumstances, and an object of the present invention is to provide a magnetometer capable of easily correcting a change in measurement sensitivity of a magnetic sensor.
【０００４】[0004]
【課題を解決するための手段】上記の目的を達成するた
め、本発明の磁気測定器は、複数の磁気センサと、該磁
気センサの出力信号を測定する測定部をケーブルで接続
し、該磁気センサを任意の位置に配置して磁界を測定す
る磁気測定器において、該磁気センサに校正信号巻線
を、測定部に校正用の直流電流源を設けると共に、前記
直流電流源から基準磁界を発生させる電流を前記校正信
号巻線に流し、その磁界を前記磁気センサにより測定
し、測定感度を補正する測定感度補正手段を備えたこと
を特徴とするものである。さらにまた、直流電流源より
正負の校正用電流を流して測定感度を補正するようにし
たことを特徴とするものである。本発明の磁気測定器は
上記のように構成されており、磁気センサの測定感度の
変化を容易に補正することができる。In order to achieve the above-mentioned object, a magnetic measuring instrument according to the present invention comprises a plurality of magnetic sensors and a measuring section for measuring an output signal of the magnetic sensors, which are connected by a cable. In a magnetometer for measuring a magnetic field by arranging a sensor at an arbitrary position, a calibration signal winding is provided in the magnetic sensor, a DC current source for calibration is provided in a measuring unit, and a reference magnetic field is generated from the DC current source. A current to be caused to flow is passed through the calibration signal winding, and a magnetic field of the current is measured by the magnetic sensor, and a measurement sensitivity correction means for correcting the measurement sensitivity is provided. Furthermore, the present invention is characterized in that a positive / negative calibration current is supplied from a DC current source to correct the measurement sensitivity. The magnetometer of the present invention is configured as described above, and can easily correct a change in the measurement sensitivity of the magnetic sensor.
【０００５】[0005]
【発明の実施の形態】以下、本発明の実施例を図面に基
づいて説明する。図１は本発明の実施例を示す磁気測定
器の概略構成図である。この磁気測定器は、磁気を検出
する磁気センサ１、２と検出信号を測定する測定部３と
前記磁気センサ１、２を独立して測定部３に接続するケ
ーブル４、５から構成されている。この磁気センサ１、
２は、一軸方向の磁気を検出することができると共に、
相互間距離及び姿勢を自由自在に配置し得るようになっ
ている。Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of a magnetometer according to an embodiment of the present invention. This magnetometer includes magnetic sensors 1 and 2 for detecting magnetism, a measuring unit 3 for measuring a detection signal, and cables 4 and 5 for connecting the magnetic sensors 1 and 2 to the measuring unit 3 independently. . This magnetic sensor 1,
2 can detect uniaxial magnetism,
The mutual distance and posture can be freely arranged.
【０００６】前記磁気センサ１、２はいずれもフラック
スゲート型であり、図２に示すように、磁気コア１ａ、
２ａに励振巻線１ｂ、２ｂ、信号巻線１ｃ、２ｃと本発
明の特徴である校正信号巻線１ｄ、２ｄがそれぞれ巻回
され、前記信号巻線１ｃ、２ｃには増幅器１ｅ、２ｅが
接続され、前記励振巻線１ｂ、２ｂには励振電源１ｆ、
２ｆが接続されている。Each of the magnetic sensors 1 and 2 is of a flux gate type, and as shown in FIG.
Excitation windings 1b and 2b, signal windings 1c and 2c, and calibration signal windings 1d and 2d, which are features of the present invention, are wound around 2a, respectively, and amplifiers 1e and 2e are connected to the signal windings 1c and 2c. The excitation windings 1b and 2b have excitation power sources 1f,
2f is connected.
【０００７】前記測定部３は、前記増幅器１ｅ、２ｅか
らの磁気検出信号をＡ／Ｄ変換するＡ／Ｄ変換器９と、
その変換データを取り込み、メモリ１２に格納したプロ
グラムに基づいて、磁界の大きさや方向などを算出して
そのデータを表示器あるいは記録計等に送出したり、測
定部３の構成要素を制御するための制御信号を出力する
ＣＰＵ１０と、前記構成要素との信号授受のためのイン
ターフェースの機能を備えたＤＩＯユニット１１と、前
記校正信号巻線１ｄ、２ｄに校正用基準磁界を発生させ
るための直流電流源８と同電流源８をオンオフするため
の切換えスイッチ６、７などから構成されている。そし
て、前記ＤＩＯユニット１１には、磁気センサ１、２の
位置を変更した場合に使用者が再補正を実行させるため
の再補正実行スイッチ１３と再補正実行中を表示するた
めの表示ランプ１９が接続されている。The measuring unit 3 includes an A / D converter 9 for A / D converting the magnetic detection signals from the amplifiers 1e and 2e,
To take in the converted data, calculate the magnitude and direction of the magnetic field based on the program stored in the memory 12, send the data to a display or a recorder, or control the components of the measuring unit 3. A DIO unit 11 having an interface function for transmitting and receiving signals to and from the components, and a DC current for generating a calibration reference magnetic field in the calibration signal windings 1d and 2d. It comprises a source 8 and changeover switches 6 and 7 for turning on and off the current source 8. The DIO unit 11 has a re-correction execution switch 13 for allowing the user to execute re-correction when the positions of the magnetic sensors 1 and 2 are changed, and a display lamp 19 for displaying that re-correction is being performed. It is connected.
【０００８】上記構成の磁気測定器による測定は次のよ
うな動作手順で行われる。例えば、ある一点での水平方
向の磁界を測定する場合には、磁気センサ１、２の測定
位置を図３のように接近させて配置する。そして、磁気
センサ１、２の相互干渉を補正するため再補正実行スイ
ッチ１３をオンにする。[0008] The measurement by the magnetometer having the above configuration is performed according to the following operation procedure. For example, when measuring a horizontal magnetic field at a certain point, the measurement positions of the magnetic sensors 1 and 2 are arranged close to each other as shown in FIG. Then, the re-correction execution switch 13 is turned on to correct the mutual interference between the magnetic sensors 1 and 2.
【０００９】再補正実行スイッチ１３がオンになると、
ＤＩＯユニット１１を介してＣＰＵ１０がオン信号を感
知し、該ＣＰＵ１０からＤＩＯユニット１１に制御信号
を送る。この制御信号はＤＩＯユニット１１により変換
され、表示ランプ１９を点灯すると共に切換えスイッチ
６がオンになる。すると、直流電流源８から校正用の規
定電流が磁気センサ１の校正信号巻線１ｄに流され、磁
気センサ１に校正用基準磁界が与えられる。When the re-correction execution switch 13 is turned on,
The CPU 10 detects the ON signal via the DIO unit 11 and sends a control signal from the CPU 10 to the DIO unit 11. This control signal is converted by the DIO unit 11, turning on the display lamp 19 and turning on the changeover switch 6. Then, a specified current for calibration flows from the DC current source 8 to the calibration signal winding 1d of the magnetic sensor 1, and a reference magnetic field for calibration is given to the magnetic sensor 1.
【００１０】この校正用基準磁界値Ｈｒは磁気センサ１
により検出され、Ａ／Ｄ変換器９でディジタル信号に変
換されＣＰＵ１０により磁気検出信号値Ｘ１として読み
取られ、測定感度Ｋ１（＝Ｈｒ／Ｘ１）が算出され、磁
気検出信号値をＸ、磁気測定値Ｈ１とした磁気算出式 Ｈ１＝（Ｈｒ／Ｘ１）Ｘ がプログラムに保存される。The calibration reference magnetic field value Hr is determined by the magnetic sensor 1
, Converted into a digital signal by the A / D converter 9, read by the CPU 10 as the magnetic detection signal value X1, the measurement sensitivity K1 (= Hr / X1) is calculated, the magnetic detection signal value is set to X, and the magnetic measurement value The magnetic calculation formula H1 = (Hr / X1) X as H1 is stored in the program.
【００１１】続いて、切換えスイッチ７がオンになる。
すると、直流電流源回路８から校正用の規定電流が磁気
センサ２の校正信号巻線２ｄに流され、磁気センサ２に
校正用基準磁界が与えられる。この校正用基準磁界値Ｈ
ｒは磁気センサ２により検出され、Ａ／Ｄ変換器９でデ
ィジタル信号に変換されＣＰＵ１０により磁気検出信号
値Ｘ２として読み取られ、測定感度Ｋ２（＝Ｈｒ／Ｘ
２）が算出され、磁気検出信号値をＸ、磁気測定値Ｈ１
とした磁気算出式 Ｈ２＝（Ｈｒ／Ｘ２）Ｘ がプログラムに保存されると共に、前記表示ランプ１９
が消灯して校正動作が終了する。以後の測定においてこ
の補正された磁気算出式を使用して磁気測定が行われ
る。なお、磁気測定器にオフセット出力が存在すると正
しい測定感度Ｋ１、Ｋ２が得られないので校正前にオフ
セットの調整をしておく必要がある。Subsequently, the changeover switch 7 is turned on.
Then, a specified current for calibration flows from the DC current source circuit 8 to the calibration signal winding 2 d of the magnetic sensor 2, and a reference magnetic field for calibration is given to the magnetic sensor 2. This calibration reference magnetic field value H
r is detected by the magnetic sensor 2, converted into a digital signal by the A / D converter 9, read as the magnetic detection signal value X2 by the CPU 10, and measured at the sensitivity K2 (= Hr / X
2) is calculated, the magnetic detection signal value is X, the magnetic measurement value H1
The magnetic calculation formula H2 = (Hr / X2) X is stored in the program, and the display lamp 19
Turns off and the calibration operation ends. In the subsequent measurement, the magnetic measurement is performed using the corrected magnetic calculation formula. If an offset output is present in the magnetometer, the correct measurement sensitivities K1 and K2 cannot be obtained, so the offset must be adjusted before calibration.
【００１２】また、本発明の実施の変形例として、正負
の校正用電流信号を用いて磁気測定器を校正することも
できる。例えば、磁気センサ１の校正用基準磁界値をＨ
ｒ、−Ｈｒに対して磁気検出信号がＸ１、−Ｘ２である
とすると、測定感度Ｋは Ｋ＝２Ｈｒ／（Ｘ１＋Ｘ２） となり、オフセットが存在しても正しい測定感度Ｋを得
ることができると共に、オフセット分（Ｘ１−Ｘ２）を
演算し測定値を補正することで、オフセットの影響を測
定値から無くすことが可能となる。さらに、磁気センサ
２についても同様にして正しい測定感度を得ることがで
きる。上記の実施例における磁気センサには、一軸方向
の磁気センサを用いているが、軸方向に用いられる磁気
コアに校正信号巻線を設けて、同様な校正を行うことに
より二軸以上のセンサに対しても、本発明を適用するこ
とができる。このように本発明は磁気センサ自体に校正
信号巻線を巻き、校正信号巻線に一定の磁界を発生させ
るための電流を供給する直流電流電源を設けると共に、
磁気センサの位置を変更した場合に、使用者が再補正を
実行させるためのスイッチを設けたことを特徴とするも
のである。As a modification of the embodiment of the present invention, the magnetometer can be calibrated using positive and negative current signals for calibration. For example, the reference magnetic field value for calibration of the magnetic sensor 1 is H
Assuming that the magnetic detection signals are X1 and -X2 with respect to r and -Hr, the measurement sensitivity K is K = 2Hr / (X1 + X2), and the correct measurement sensitivity K can be obtained even if an offset exists. By calculating the offset (X1−X2) and correcting the measured value, it is possible to eliminate the influence of the offset from the measured value. Further, the correct measurement sensitivity can be obtained for the magnetic sensor 2 in the same manner. Although the magnetic sensor in the above embodiment uses a uniaxial magnetic sensor, a calibration signal winding is provided on a magnetic core used in the axial direction, and by performing the same calibration, a sensor having two or more axes is obtained. The present invention can also be applied to this. As described above, the present invention winds the calibration signal winding around the magnetic sensor itself, and provides a DC current power supply that supplies a current for generating a constant magnetic field in the calibration signal winding,
When the position of the magnetic sensor is changed, a switch is provided for the user to execute re-correction.
【００１３】[0013]
【発明の効果】本発明の磁気測定器は上記のように構成
されており、磁気測定器内に設けられた校正手段によ
り、磁気センサの配置を変える毎に容易に測定感度の校
正ができ、磁気センサのどのような配置に対しても正確
な測定を行うことができる。また、正負の校正電流を流
して校正することにより、磁気測定器にオフセットが存
在しても正確な測定感度の校正を行うことができる。The magnetometer according to the present invention is configured as described above. Calibration means provided in the magnetometer can easily calibrate the measurement sensitivity every time the arrangement of the magnetic sensor is changed. Accurate measurements can be made for any arrangement of magnetic sensors. Further, by performing the calibration by flowing the positive and negative calibration currents, it is possible to accurately calibrate the measurement sensitivity even if an offset exists in the magnetometer.
【図１】本発明の磁気測定器の実施例の概略図である。FIG. 1 is a schematic view of an embodiment of a magnetometer according to the present invention.
【図２】本発明に係わる磁気センサの概略図である。FIG. 2 is a schematic diagram of a magnetic sensor according to the present invention.
【図３】実施例における磁気センサの配置図である。FIG. 3 is a layout diagram of a magnetic sensor in the embodiment.
【図４】従来の磁気測定器の概略図である。FIG. 4 is a schematic diagram of a conventional magnetometer.
【図５】従来の磁気測定器の磁気センサの配置図であ
る。FIG. 5 is a layout view of a magnetic sensor of a conventional magnetometer.
１、２、１４、１５…磁気センサ １ａ、２ａ…磁気コア １ｂ、２ｂ…励振巻線 １ｃ、２ｃ…信号巻線 １ｄ、２ｄ…校正信号巻線 １ｅ、２ｅ…増幅器 １ｆ、２ｆ…励振電源 ３…測定部 ４、５、１６、１７…ケーブル ６、７…切換えスイッチ ８…直流電流源 ９…Ａ／Ｄ変換器 １０…ＣＰＵ １１…ＤＩＯユニット １２…メモリ １３…再補正実行スイッチ １８…電子回路ユニット １９…表示ランプ 1, 2, 14, 15 ... magnetic sensor 1a, 2a ... magnetic core 1b, 2b ... excitation winding 1c, 2c ... signal winding 1d, 2d ... calibration signal winding 1e, 2e ... amplifier 1f, 2f ... excitation power supply 3 ... Measurement part 4,5,16,17 ... Cable 6,7 ... Changeover switch 8 ... DC current source 9 ... A / D converter 10 ... CPU 11 ... DIO unit 12 ... Memory 13 ... Re-correction execution switch 18 ... Electronic circuit Unit 19: Indicator lamp
Claims (2)
信号を測定する測定部をケーブルで接続し、該磁気セン
サを任意の位置に配置して磁界を測定する磁気測定器に
おいて、該磁気センサに校正信号巻線を、測定部に校正
用の直流電流源を設けると共に、前記直流電流源から基
準磁界を発生させる電流を前記校正信号巻線に流し、そ
の磁界を前記磁気センサにより測定し、測定感度を補正
する測定感度補正手段を備えたことを特徴とする磁気測
定器。A magnetic measuring device for connecting a plurality of magnetic sensors and a measuring unit for measuring an output signal of the magnetic sensors by a cable and arranging the magnetic sensors at an arbitrary position to measure a magnetic field. A calibration signal winding is provided on the sensor, and a DC current source for calibration is provided on the measurement unit.A current for generating a reference magnetic field from the DC current source is supplied to the calibration signal winding, and the magnetic field is measured by the magnetic sensor. And a measuring sensitivity correcting means for correcting the measuring sensitivity.
測定感度を補正するようにしたことを特徴とする請求項
１記載の磁気測定器。2. The magnetometer according to claim 1, wherein a positive / negative calibration current is supplied from a DC current source to correct the measurement sensitivity.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2000201861A JP4310895B2 (en) | 2000-07-04 | 2000-07-04 | Magnetic measuring instrument |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2000201861A JP4310895B2 (en) | 2000-07-04 | 2000-07-04 | Magnetic measuring instrument |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2002022814A true JP2002022814A (en) | 2002-01-23 |
| JP4310895B2 JP4310895B2 (en) | 2009-08-12 |
Family
ID=18699470
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|---|---|---|---|
| JP2000201861A Expired - Lifetime JP4310895B2 (en) | 2000-07-04 | 2000-07-04 | Magnetic measuring instrument |
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| JP2014235086A (en) * | 2013-06-03 | 2014-12-15 | 三菱電機株式会社 | Current detector |
| CN105676151A (en) * | 2016-01-18 | 2016-06-15 | 华东师范大学 | Negative feedback type magnetic field sensor |
| JP2017534063A (en) * | 2014-11-14 | 2017-11-16 | アレグロ・マイクロシステムズ・エルエルシー | Magnetic field sensor with calibration circuit and calibration technique |
| JP2019060717A (en) * | 2017-09-26 | 2019-04-18 | 笹田磁気計測研究所株式会社 | Sensor head module and magnetometric sensor |
| CN111722168A (en) * | 2019-03-22 | 2020-09-29 | 宇能电科技股份有限公司 | Correction magnetic field generating device, magnetic field sensor and correction method thereof |
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2000
- 2000-07-04 JP JP2000201861A patent/JP4310895B2/en not_active Expired - Lifetime
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005182115A (en) * | 2003-12-16 | 2005-07-07 | Sankyo Seiki Mfg Co Ltd | Driving circuit of paper sheet discriminating sensor and paper sheet discriminating device |
| JP4507585B2 (en) * | 2003-12-16 | 2010-07-21 | 日本電産サンキョー株式会社 | Drive circuit for paper sheet identification sensor and paper sheet identification device |
| JP2014235086A (en) * | 2013-06-03 | 2014-12-15 | 三菱電機株式会社 | Current detector |
| JP2017534063A (en) * | 2014-11-14 | 2017-11-16 | アレグロ・マイクロシステムズ・エルエルシー | Magnetic field sensor with calibration circuit and calibration technique |
| CN105676151A (en) * | 2016-01-18 | 2016-06-15 | 华东师范大学 | Negative feedback type magnetic field sensor |
| JP2019060717A (en) * | 2017-09-26 | 2019-04-18 | 笹田磁気計測研究所株式会社 | Sensor head module and magnetometric sensor |
| JP7002112B2 (en) | 2017-09-26 | 2022-01-20 | 笹田磁気計測研究所株式会社 | Sensor head module and magnetic sensor |
| CN111722168A (en) * | 2019-03-22 | 2020-09-29 | 宇能电科技股份有限公司 | Correction magnetic field generating device, magnetic field sensor and correction method thereof |
| CN111722168B (en) * | 2019-03-22 | 2023-04-25 | 宇能电科技股份有限公司 | Correction magnetic field generating device, magnetic field sensor and correction method thereof |
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