JP2011159668A - Active magnetic shield device - Google Patents

Active magnetic shield device Download PDF

Info

Publication number
JP2011159668A
JP2011159668A JP2010017927A JP2010017927A JP2011159668A JP 2011159668 A JP2011159668 A JP 2011159668A JP 2010017927 A JP2010017927 A JP 2010017927A JP 2010017927 A JP2010017927 A JP 2010017927A JP 2011159668 A JP2011159668 A JP 2011159668A
Authority
JP
Japan
Prior art keywords
magnetic field
compensation coil
control signal
field compensation
signal
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.)
Withdrawn
Application number
JP2010017927A
Other languages
Japanese (ja)
Inventor
Masahiko Nakajima
雅彦 中島
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Seiko Epson Corp
Original Assignee
Seiko Epson Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Seiko Epson Corp filed Critical Seiko Epson Corp
Priority to JP2010017927A priority Critical patent/JP2011159668A/en
Publication of JP2011159668A publication Critical patent/JP2011159668A/en
Withdrawn legal-status Critical Current

Links

Images

Abstract

<P>PROBLEM TO BE SOLVED: To reduce a power consumption of a large-sized active magnetic shield device. <P>SOLUTION: The active magnetic shield device 1 includes: magnetic field compensation coils 101, 102; a magnetic sensor 200 which measures an environmental magnetic field; a control signal generation portion 300 which generates a control signal Vc based upon a measurement signal Vb from the magnetic sensor 200; and a driving signal generation portion 400 which generates a driving signal Ib for driving the magnetic field compensation coils 101, 102 based upon the control signal Vc, wherein the control signal generation portion 300 outputs the control signal Vc with a pulse-width modulation signal when variation of the measurement signal Vb is within a predetermined range and outputs the control signal Vc with a voltage signal when variation of the measurement signal Vb is not within the predetermined range. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

本発明は、環境磁場を打ち消す補償磁場発生用の補償コイルが配置されたアクティブ磁気シールド装置に関する。   The present invention relates to an active magnetic shield device in which a compensation coil for generating a compensation magnetic field that cancels an environmental magnetic field is arranged.

地磁気に比べて微小な心臓磁場や脳磁場などを測定するための超電導量子干渉素子（ＳＱＵＩＤ；Ｓｕｐｅｒｃｏｎｄｕｃｔｉｎｇ Ｑｕａｎｔｕｍ ｉｎｔｅｒｆｅｒｅｎｃｅ Ｄｅｖｉｃｅ）装置などは、建物周囲の環境磁場（磁気ノイズ）の影響を極力遮蔽する必要がある。そのため、ＳＱＵＩＤ装置などは、環境磁場から遮蔽するための透磁率の高い電磁鋼板・パーマロイ等の磁性材料板で囲まれたパッシブ（受動）磁気シールド室の中に設置する必要がある。   A superconducting quantum interference device (SQUID) device that measures a minute heart magnetic field, brain magnetic field, and the like compared to geomagnetism needs to shield the influence of environmental magnetic field (magnetic noise) around the building as much as possible. is there. For this reason, the SQUID device or the like needs to be installed in a passive magnetic shield chamber surrounded by a magnetic material plate such as an electromagnetic steel plate or permalloy having a high magnetic permeability for shielding from an environmental magnetic field.

しかしながら、このようなパッシブ磁気シールド室では、建物のそばを、自動車や電車が通過する等により発生する、急峻な外部からの強い環境磁場に対して、対処できないという問題がある。   However, such a passive magnetic shield room has a problem that it cannot cope with a steep external strong magnetic field generated by a car or a train passing by a building.

この問題を解決するために、例えば特許文献１には、環境磁場の変動に応じて同振幅・逆位相の補償磁場を、補償コイルにより発生させて環境磁場の変動を打ち消すアクティブ（能動）磁気シールドの方法が記載されている。   In order to solve this problem, for example, Patent Document 1 discloses an active magnetic shield in which a compensation magnetic field having the same amplitude and antiphase is generated by a compensation coil in accordance with a change in the environmental magnetic field to cancel the change in the environmental magnetic field. The method is described.

特開２００２−２３２１８２号公報（図１）Japanese Patent Laying-Open No. 2002-232182 (FIG. 1)

しかしながら、従来の方法では、補償コイルが大型の場合、常に大量の駆動電流を流す必要があり、アクティブ磁気シールド装置の低消費電力化ができないという課題がある。   However, in the conventional method, when the compensation coil is large, it is necessary to always flow a large amount of drive current, and there is a problem that the power consumption of the active magnetic shield device cannot be reduced.

本発明は、上述の課題の少なくとも一部を解決するためになされたものであり、以下の形態または適用例として実現することが可能である。   SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

［適用例１］本適用例のアクティブ磁気シールド装置は、磁場補償コイルと、環境磁場を計測する磁気センサーと、前記磁気センサーからの計測信号に基づいて制御信号を発生する制御信号発生部と、前記磁場補償コイルを駆動するための駆動信号を前記制御信号に基づき発生する駆動信号発生部と、を含み、前記制御信号発生部は、前記計測信号の変動が所定の範囲以内の場合は前記制御信号をパルス幅変調信号で出力し、前記計測信号の変動が前記所定の範囲にない場合は前記制御信号を電圧信号で出力する、ことを特徴とする。   Application Example 1 An active magnetic shield device according to this application example includes a magnetic field compensation coil, a magnetic sensor that measures an environmental magnetic field, a control signal generator that generates a control signal based on a measurement signal from the magnetic sensor, A drive signal generator for generating a drive signal for driving the magnetic field compensation coil based on the control signal, and the control signal generator is configured to control the control signal when a variation in the measurement signal is within a predetermined range. The signal is output as a pulse width modulation signal, and the control signal is output as a voltage signal when the variation of the measurement signal is not within the predetermined range.

この構成によれば、駆動信号発生部を１００％幅の電圧信号で制御する場合の消費電力に比べ、１００％未満のデューティー比のパルス幅変調信号で制御することにより、消費電力をデューティー比に応じて低く抑えることができる。従って、地磁気のような安定した環境磁場をキャンセルするためにパルス幅変調信号で駆動信号発生部を制御することにより、消費電力を低減することができる。   According to this configuration, the power consumption is changed to the duty ratio by controlling with the pulse width modulation signal having a duty ratio of less than 100%, compared to the power consumption when the drive signal generator is controlled with the voltage signal having a width of 100%. It can be kept low accordingly. Therefore, the power consumption can be reduced by controlling the drive signal generator with the pulse width modulation signal in order to cancel a stable environmental magnetic field such as geomagnetism.

［適用例２］上記に記載のアクティブ磁気シールド装置において、前記アクティブ磁気シールド装置は、前記磁場補償コイルから構成される第１の磁場補償コイル及び第２の磁場補償コイルを備え、前記第１の磁場補償コイルを含む面と前記第２の磁場補償コイルを含む面とは互いに並行に配置され、前記第１の磁場補償コイルと前記第２の磁場補償コイルとは、電気的に直列に接続されている、ことを特徴とする。   Application Example 2 In the active magnetic shield device described above, the active magnetic shield device includes a first magnetic field compensation coil and a second magnetic field compensation coil configured by the magnetic field compensation coil. The surface including the magnetic field compensation coil and the surface including the second magnetic field compensation coil are arranged in parallel to each other, and the first magnetic field compensation coil and the second magnetic field compensation coil are electrically connected in series. It is characterized by that.

この構成によれば、第１の磁場補償コイルと第２の磁場補償コイルとによりヘルムホルツコイルを構成することができるので、勾配磁場の少ない磁場環境を実現できる。   According to this configuration, since the Helmholtz coil can be configured by the first magnetic field compensation coil and the second magnetic field compensation coil, a magnetic field environment with a small gradient magnetic field can be realized.

［適用例３］上記に記載のアクティブ磁気シールド装置において、前記磁場補償コイルから構成される第１の磁場補償コイル及び第２の磁場補償コイルをＸ軸，Ｙ軸，Ｚ軸に構成したことが好ましい。   Application Example 3 In the active magnetic shield device described above, the first magnetic field compensation coil and the second magnetic field compensation coil configured from the magnetic field compensation coil are configured on the X axis, the Y axis, and the Z axis. preferable.

第１実施形態に係るアクティブ磁気シールド装置の構成を示す概略図。Schematic which shows the structure of the active magnetic shielding apparatus which concerns on 1st Embodiment. 第１実施形態に係るアクティブ磁気シールド装置の動作を示すタイミング図。The timing diagram which shows operation | movement of the active magnetic shielding apparatus which concerns on 1st Embodiment.

以下、アクティブ磁気シールド装置の実施形態について図面に従って説明する。   Hereinafter, embodiments of an active magnetic shield device will be described with reference to the drawings.

（第１実施形態）
＜アクティブ磁気シールド装置の構成＞
先ず、第１実施形態に係るアクティブ磁気シールド装置の構成について、図１を参照して説明する。図１は、第１実施形態に係るアクティブ磁気シールド装置の構成を示す概略図である。 (First embodiment)
<Configuration of active magnetic shield device>
First, the configuration of the active magnetic shield device according to the first embodiment will be described with reference to FIG. FIG. 1 is a schematic diagram showing the configuration of the active magnetic shield device according to the first embodiment.

図１に示すように、アクティブ磁気シールド装置１は、第１の磁場補償コイル１０１と、第２の磁場補償コイル１０２と、磁気センサー２００と、制御信号発生部３００と、駆動信号発生部４００と、から構成されている。第１の磁場補償コイル１０１及び第２の磁場補償コイル１０２は、各々、銅などの配線材を２次元的に例えば円形に複数回巻いて作られている。   As shown in FIG. 1, the active magnetic shield device 1 includes a first magnetic field compensation coil 101, a second magnetic field compensation coil 102, a magnetic sensor 200, a control signal generator 300, and a drive signal generator 400. , Is composed of. Each of the first magnetic field compensation coil 101 and the second magnetic field compensation coil 102 is formed by winding a wiring material such as copper two-dimensionally, for example, a plurality of times in a circular shape.

磁気センサー２００は、フラックス・ゲートセンサーや磁気インピーダンス素子、ホール素子、磁気抵抗効果素子などで構成され、環境磁場を電圧値などに変換して計測信号Ｖｂを出力する。制御信号発生部３００は、計測信号Ｖｂに基づいて制御信号Ｖｃを発生する。駆動信号発生部４００は、制御信号Ｖｃに基づき第１の磁場補償コイル１０１と第２の磁場補償コイル１０２を駆動するための電流量を制御し駆動信号Ｉｂとして出力する。   The magnetic sensor 200 includes a flux gate sensor, a magnetic impedance element, a Hall element, a magnetoresistive effect element, and the like, converts an environmental magnetic field into a voltage value, and outputs a measurement signal Vb. The control signal generator 300 generates a control signal Vc based on the measurement signal Vb. The drive signal generator 400 controls the amount of current for driving the first magnetic field compensation coil 101 and the second magnetic field compensation coil 102 based on the control signal Vc, and outputs it as a drive signal Ib.

第１の磁場補償コイル１０１を含む面と第２の磁場補償コイル１０２を含む面とは、それぞれＸ軸上にコイル中心が来るように向き合って、互いに並行に配置されている。また、第１の磁場補償コイル１０１と第２の磁場補償コイル１０２とは、駆動信号発生部４００の駆動信号Ｉｂが直列に流れるように接続されている。第１の磁場補償コイル１０１と第２の磁場補償コイル１０２とをこのように配置することにより、Ｘ軸上にヘルムホルツコイルが構成される。磁気センサー２００は、Ｘ軸上において、第１の磁場補償コイル１０１と第２の磁場補償コイル１０２との中央に配置されている。   The surface including the first magnetic field compensation coil 101 and the surface including the second magnetic field compensation coil 102 are arranged in parallel so as to face each other so that the coil center comes on the X axis. The first magnetic field compensation coil 101 and the second magnetic field compensation coil 102 are connected so that the drive signal Ib of the drive signal generator 400 flows in series. By arranging the first magnetic field compensation coil 101 and the second magnetic field compensation coil 102 in this way, a Helmholtz coil is configured on the X axis. The magnetic sensor 200 is disposed at the center of the first magnetic field compensation coil 101 and the second magnetic field compensation coil 102 on the X axis.

＜アクティブ磁気シールド装置の動作＞
次に、第１実施形態に係るアクティブ磁気シールド装置の動作について、図２を参照して説明する。図２は、第１実施形態に係るアクティブ磁気シールド装置の動作を示すタイミング図である。 <Operation of active magnetic shield device>
Next, the operation of the active magnetic shield device according to the first embodiment will be described with reference to FIG. FIG. 2 is a timing chart showing the operation of the active magnetic shield device according to the first embodiment.

図２は、計測信号Ｖｂと制御信号Ｖｃと駆動信号Ｉｂとの変化を時間軸に沿って示している。なお、磁気センサー２００は、図１のＸ軸において、正（Ｘ軸の矢印方向）の向きに磁束密度が発生している場合には正の電圧値の計測信号Ｖｂを出力し、負の向きに磁束密度が発生している場合には負の電圧値の計測信号Ｖｂを出力するものとする。また、制御信号発生部３００は、計測信号Ｖｂが正の電圧値の場合には負の方向に磁束密度を発生するように、第１の磁場補償コイル１０１と第２の磁場補償コイル１０２とを駆動する駆動信号Ｉｂを駆動信号発生部４００が発生するように制御信号Ｖｃを発生し、計測信号Ｖｂが負の電圧値の場合には正の方向に磁束密度を発生するように、第１の磁場補償コイル１０１と第２の磁場補償コイル１０２とを駆動する駆動信号Ｉｂを駆動信号発生部４００が発生するように制御信号Ｖｃを発生する。   FIG. 2 shows changes in the measurement signal Vb, the control signal Vc, and the drive signal Ib along the time axis. The magnetic sensor 200 outputs a measurement signal Vb having a positive voltage value in the negative direction when the magnetic flux density is generated in the positive (X-axis arrow direction) direction on the X axis in FIG. When a magnetic flux density is generated in the negative signal, a measurement signal Vb having a negative voltage value is output. Further, the control signal generator 300 causes the first magnetic field compensation coil 101 and the second magnetic field compensation coil 102 to generate a magnetic flux density in the negative direction when the measurement signal Vb has a positive voltage value. The control signal Vc is generated so that the drive signal generator 400 generates the drive signal Ib to be driven. When the measurement signal Vb has a negative voltage value, the first magnetic flux density is generated in the positive direction. A control signal Vc is generated so that the drive signal generator 400 generates a drive signal Ib for driving the magnetic field compensation coil 101 and the second magnetic field compensation coil 102.

図２において、時点ｔ０では、環境磁場である地磁気の影響でＸ軸の負の方向に磁束密度が発生している例を示し、計測信号Ｖｂは負の電圧値ｖ１を出力している。   FIG. 2 shows an example in which the magnetic flux density is generated in the negative direction of the X axis due to the influence of geomagnetism, which is an environmental magnetic field, at time t0, and the measurement signal Vb outputs a negative voltage value v1.

時点ｔ１において、制御信号発生部３００は計測信号Ｖｂが０Ｖになるように、駆動信号Ｉｂの電流値として正の電流値ｉ１を駆動信号発生部４００が発生するように、制御信号Ｖｃを正の電圧信号ｃ１で出力する。これに伴い、計測信号Ｖｂは０Ｖに遷移する。   At time t1, the control signal generator 300 sets the control signal Vc to a positive value so that the drive signal generator 400 generates a positive current value i1 as the current value of the drive signal Ib so that the measurement signal Vb becomes 0V. Output with voltage signal c1. Along with this, the measurement signal Vb transits to 0V.

時点ｔ２において、制御信号発生部３００は、計測信号Ｖｂの変動が所定の範囲（例えば−０．０１Ｖから＋０．０１Ｖの範囲）以内であると判定し、制御信号Ｖｃを計測信号Ｖｂが０Ｖを保つために必要なデューティー比のパルス幅変調信号に切り換え、計測信号Ｖｂの変動が所定の範囲を超えるまでの期間（時点ｔ２〜ｔ３）、制御信号Ｖｃを出力し続ける。   At time t2, the control signal generator 300 determines that the fluctuation of the measurement signal Vb is within a predetermined range (for example, a range of −0.01V to + 0.01V), and the control signal Vc is set to 0V. The control is switched to the pulse width modulation signal having a duty ratio necessary for maintaining, and the control signal Vc is continuously output until the fluctuation of the measurement signal Vb exceeds a predetermined range (time t2 to t3).

時点ｔ３において、外部の影響によりＸ軸の正の方向の外乱磁場が発生し、計測信号Ｖｂの電圧値がｖ２に跳ね上がったので、制御信号発生部３００は計測信号Ｖｂが０Ｖになるように、駆動信号Ｉｂの電流値として負の電流値ｉ２を駆動信号発生部４００が発生するように、制御信号Ｖｃを負の電圧信号ｃ２で出力する。これに伴い、計測信号Ｖｂは０Ｖに遷移する。   At time t3, a disturbance magnetic field in the positive direction of the X axis is generated due to an external influence, and the voltage value of the measurement signal Vb jumps up to v2, so that the control signal generator 300 causes the measurement signal Vb to be 0V. The control signal Vc is output as a negative voltage signal c2 so that the drive signal generator 400 generates a negative current value i2 as the current value of the drive signal Ib. Along with this, the measurement signal Vb transits to 0V.

時点ｔ４において、制御信号発生部３００は、計測信号Ｖｂの変動が所定の範囲以内であると判定し、制御信号Ｖｃを計測信号Ｖｂが０Ｖを保つために必要なデューティー比のパルス幅変調信号に切り換え、計測信号Ｖｂの変動が所定の範囲を超えるまでの期間（時点ｔ４〜ｔ５）、制御信号Ｖｃを出力し続ける。   At time t4, the control signal generator 300 determines that the variation of the measurement signal Vb is within a predetermined range, and converts the control signal Vc to a pulse width modulation signal having a duty ratio necessary for the measurement signal Vb to keep 0V. The control signal Vc is continuously output during the period (time t4 to t5) until the change of the measurement signal Vb exceeds the predetermined range.

時点ｔ５では、環境磁場に外部の影響によりＸ軸の負の方向の外乱磁場が発生し、計測信号Ｖｂの電圧値がｖ３に下がったので、制御信号発生部３００は計測信号Ｖｂが０Ｖになるように、駆動信号Ｉｂの電流値として正の電流値ｉ３を駆動信号発生部４００が発生するように、制御信号Ｖｃを正の電圧信号ｃ１で出力する。これに伴い、計測信号Ｖｂは０Ｖに遷移する。   At time t5, a disturbance magnetic field in the negative direction of the X axis is generated due to the external influence on the environmental magnetic field, and the voltage value of the measurement signal Vb has dropped to v3. As described above, the control signal Vc is output as the positive voltage signal c1 so that the drive signal generator 400 generates the positive current value i3 as the current value of the drive signal Ib. Along with this, the measurement signal Vb transits to 0V.

時点ｔ６において、制御信号発生部３００は、計測信号Ｖｂの変動が所定の範囲以内であると判定し、制御信号Ｖｃを計測信号Ｖｂが０Ｖを保つために必要なデューティー比のパルス幅変調信号に切り換え、計測信号Ｖｂの変動が所定の範囲を超えるまでの期間（時点ｔ４〜ｔ５）、制御信号Ｖｃを出力し続ける。   At time t6, the control signal generator 300 determines that the variation of the measurement signal Vb is within a predetermined range, and converts the control signal Vc to a pulse width modulation signal having a duty ratio necessary for the measurement signal Vb to keep 0V. The control signal Vc is continuously output during the period (time t4 to t5) until the change of the measurement signal Vb exceeds the predetermined range.

以上に述べた本実施形態によれば、以下の効果が得られる。   According to the present embodiment described above, the following effects can be obtained.

本実施形態では、駆動信号発生部４００を１００％幅の電圧信号で制御する場合の消費電力に比べ、１００％未満のデューティー比のパルス幅変調信号で制御することにより消費電力をデューティー比に応じて低く抑えることができる。従って、地磁気のような安定した環境磁場をキャンセルするためにパルス幅変調信号で駆動信号発生部４００を制御することにより、消費電力を低減することができる。   In the present embodiment, the power consumption is controlled according to the duty ratio by controlling with the pulse width modulation signal having a duty ratio of less than 100%, compared to the power consumption when the drive signal generator 400 is controlled with a voltage signal having a width of 100%. Can be kept low. Therefore, the power consumption can be reduced by controlling the drive signal generator 400 with the pulse width modulation signal in order to cancel a stable environmental magnetic field such as geomagnetism.

以上、アクティブ磁気シールド装置の実施形態を説明したが、こうした実施の形態に何ら限定されるものではなく、趣旨を逸脱しない範囲内において様々な形態で実施し得ることができる。以下、変形例を挙げて説明する。   As mentioned above, although embodiment of the active magnetic shield apparatus was described, it is not limited to such embodiment at all, It can implement in various forms within the range which does not deviate from the meaning. Hereinafter, a modification will be described.

（変形例１）
アクティブ磁気シールド装置の変形例について説明する。前述の実施形態では、Ｘ軸に第１の磁場補償コイル１０１と第２の磁場補償コイル１０２とで構成されるヘルムホルツコイルを配置したが、Ｙ軸、Ｚ軸にも構成し、Ｘ，Ｙ，Ｚ軸の３軸用の磁気センサー２００で構成すれば、Ｘ，Ｙ，Ｚすべての方向に対して地磁気や外乱磁場をキャンセルできる。 (Modification 1)
A modification of the active magnetic shield device will be described. In the above-described embodiment, the Helmholtz coil composed of the first magnetic field compensation coil 101 and the second magnetic field compensation coil 102 is arranged on the X axis, but it is also constructed on the Y axis and the Z axis. If the three-axis magnetic sensor 200 for the Z axis is used, the geomagnetism and the disturbance magnetic field can be canceled in all X, Y, and Z directions.

１…アクティブ磁気シールド装置、１０１…第１の磁場補償コイル、１０２…第２の磁場補償コイル、２００…磁気センサー、３００…制御信号発生部、４００…駆動信号発生部。   DESCRIPTION OF SYMBOLS 1 ... Active magnetic shield apparatus, 101 ... 1st magnetic field compensation coil, 102 ... 2nd magnetic field compensation coil, 200 ... Magnetic sensor, 300 ... Control signal generation part, 400 ... Drive signal generation part.

Claims (3)

磁場補償コイルと、
環境磁場を計測する磁気センサーと、
前記磁気センサーからの計測信号に基づいて制御信号を発生する制御信号発生部と、
前記磁場補償コイルを駆動するための駆動信号を前記制御信号に基づき発生する駆動信号発生部と、
を含み、
前記制御信号発生部は、前記計測信号の変動が所定の範囲以内の場合は前記制御信号をパルス幅変調信号で出力し、前記計測信号の変動が前記所定の範囲にない場合は前記制御信号を電圧信号で出力する、
ことを特徴とするアクティブ磁気シールド装置。 A magnetic field compensation coil;
A magnetic sensor that measures the environmental magnetic field;
A control signal generator for generating a control signal based on a measurement signal from the magnetic sensor;
A drive signal generator for generating a drive signal for driving the magnetic field compensation coil based on the control signal;
Including
The control signal generator outputs the control signal as a pulse width modulation signal when the variation of the measurement signal is within a predetermined range, and outputs the control signal when the variation of the measurement signal is not within the predetermined range. Output with voltage signal,
An active magnetic shield device. 請求項１に記載のアクティブ磁気シールド装置において、前記磁場補償コイルから構成される第１の磁場補償コイル及び第２の磁場補償コイルを備え、前記第１の磁場補償コイルを含む面と前記第２の磁場補償コイルを含む面とは互いに並行に配置され、前記第１の磁場補償コイルと前記第２の磁場補償コイルとは、電気的に直列に接続されている、
ことを特徴とするアクティブ磁気シールド装置。 2. The active magnetic shield device according to claim 1, comprising a first magnetic field compensation coil and a second magnetic field compensation coil configured by the magnetic field compensation coil, and a surface including the first magnetic field compensation coil and the second magnetic field compensation coil. Are arranged in parallel with each other, and the first magnetic field compensation coil and the second magnetic field compensation coil are electrically connected in series.
An active magnetic shield device. 請求項２に記載のアクティブ磁気シールド装置において、前記磁場補償コイルから構成される第１の磁場補償コイル及び第２の磁場補償コイルをＸ軸，Ｙ軸，Ｚ軸に構成したことを特徴とするアクティブ磁気シールド装置。   3. The active magnetic shield device according to claim 2, wherein the first magnetic field compensation coil and the second magnetic field compensation coil configured from the magnetic field compensation coil are configured in an X axis, a Y axis, and a Z axis. Active magnetic shield device.
JP2010017927A 2010-01-29 2010-01-29 Active magnetic shield device Withdrawn JP2011159668A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2010017927A JP2011159668A (en) 2010-01-29 2010-01-29 Active magnetic shield device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2010017927A JP2011159668A (en) 2010-01-29 2010-01-29 Active magnetic shield device

Publications (1)

Publication Number Publication Date
JP2011159668A true JP2011159668A (en) 2011-08-18

Family

ID=44591399

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2010017927A Withdrawn JP2011159668A (en) 2010-01-29 2010-01-29 Active magnetic shield device

Country Status (1)

Country Link
JP (1) JP2011159668A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013162065A (en) * 2012-02-08 2013-08-19 Seiko Epson Corp Magnetic shield device, magnetic shield device demagnetizing method, and program
US20200350106A1 (en) * 2019-05-03 2020-11-05 Hi Llc Magnetic field generator for a magnetic field measurement system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2013162065A (en) * 2012-02-08 2013-08-19 Seiko Epson Corp Magnetic shield device, magnetic shield device demagnetizing method, and program
US20200350106A1 (en) * 2019-05-03 2020-11-05 Hi Llc Magnetic field generator for a magnetic field measurement system

Similar Documents

Publication Publication Date Title
EP3143420B1 (en) Bipolar chopping for i/f noise and offset reduction in magnetic field sensors
JP6672259B2 (en) Current converter with fluxgate detector
JP2009222179A (en) Shock buffering device
US10744531B2 (en) Multi-core, multi-dimension electromagnet
JP5758450B2 (en) Magnetic sensor driving circuit, magnetic sensor, current sensor, and magnetic sensor driving method
Hu et al. 1/f noise suppression of giant magnetoresistive sensors with vertical motion flux modulation
JP2008282983A (en) Magnetic shield equipment
JP3905039B2 (en) MRI equipment
JP2011159668A (en) Active magnetic shield device
JP2011146621A (en) Active magnetic shielding device
US20190113544A1 (en) Magnetic sensor and current sensor including the same
CN109411181A (en) Integral demagnetization method of small multilayer combined magnetic shielding system
JP2014228418A (en) Current sensor
EP3450987A2 (en) Speed detecting device and stray magnetic field suppressing method
WO2013147207A1 (en) Measurement method for magnetic field strength, flux-gate magnetic element, and magnetic sensor
JPS59230117A (en) Electromagnetic force generating device
JPS5814056B2 (en) Vehicle demagnetizer
JP2019211450A (en) Magnetic field sensor
KR20150116353A (en) Electromagnetic actuator
JP2005147947A (en) Core for magnetic sensor, magnetic sensor, and flux gate magnetometer
JPH11330768A (en) Magnetic shielding device
JP2009261422A (en) Magnetic resonance imaging apparatus
Angelopoulos et al. Design and development of a high-sensitivity, portable, and low-cost fluxgate magnetometer
JP3693165B2 (en) Magnetic shield characteristic measuring device
JP2019181041A (en) Active magnetic shield system and magnetocardiograph system using the same

Legal Events

Date Code Title Description
A300 Withdrawal of application because of no request for examination

Free format text: JAPANESE INTERMEDIATE CODE: A300

Effective date: 20130402