JPH10332745A - Electric current sensor - Google Patents
Electric current sensorInfo
- Publication number
- JPH10332745A JPH10332745A JP9157852A JP15785297A JPH10332745A JP H10332745 A JPH10332745 A JP H10332745A JP 9157852 A JP9157852 A JP 9157852A JP 15785297 A JP15785297 A JP 15785297A JP H10332745 A JPH10332745 A JP H10332745A
- Authority
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- Japan
- Prior art keywords
- current
- component detection
- component
- core
- coil
- Prior art date
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Abstract
Description
【０００１】[0001]
【発明の属する技術分野】この発明は、被検出導線中に
直流電流及び交流電流が共に流れるような場合におい
て、それらの電流が重畳された状態での出力特性を測定
する必要がある用途、例えば、電気自動車におけるバッ
テリーの充電量、放電量の管理用センサーとして有効で
あり、しかも、比較的小電流から大電流までの広範囲の
電流測定が可能な電流センサーに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an application where it is necessary to measure output characteristics in a state where a direct current and an alternating current flow together in a conductor to be detected, in a state where those currents are superimposed. The present invention relates to a current sensor that is effective as a sensor for managing the amount of charge and discharge of a battery in an electric vehicle, and that can measure a wide range of current from a relatively small current to a large current.
【０００２】[0002]
【従来の技術】最近、電気自動車におけるバッテリーの
充・放電量の管理用センサーなどでは、被検出導線中を
流れる電流の状態をそのまま検出することが要求され、
すなわち、一つの被検出導線中に直流電流及び交流電流
が共に流れるような場合に、それらの電流が重畳された
状態での出力特性（時間当たりの電流量）を測定するこ
とが要求されている。2. Description of the Related Art Recently, sensors for controlling the amount of charge / discharge of a battery in an electric vehicle are required to directly detect the state of a current flowing through a detected wire.
That is, when both a direct current and an alternating current flow in one detected wire, it is required to measure an output characteristic (current amount per time) in a state where those currents are superimposed. .
【０００３】従来から、被検出導線中を流れる直流電流
または交流電流を単独で測定するセンサーは種々提案さ
れており、本願出願人も、構造が比較的簡単であり、微
小な電流から比較的大きな電流までの電流変化（例え
ば、０．２Ａ〜２０Ａ程度）に対して直線性に優れた検
出能力を有する高感度の直流電流センサーを提案した
（特開平７−１２８３７３号）。Hitherto, various sensors have been proposed for independently measuring a direct current or an alternating current flowing through a detection target wire. The applicant of the present application has a relatively simple structure, and a small current to a relatively large current. A highly sensitive DC current sensor having a detection capability with excellent linearity with respect to a current change up to the current (for example, about 0.2 A to 20 A) has been proposed (Japanese Patent Laid-Open No. 7-128373).
【０００４】この直流電流センサーは、環状の軟質磁性
材料からなるコアに、励磁コイル及び検出コイルをトロ
イダル状に巻回配置した最も簡単な構成において、励磁
コイルにコアの保磁力を超える磁場を発生させる三角波
状の励磁電流を流した時、コア内の磁束の向きが反転す
ることに着目し、この反転のタイミングを検出コイルに
発生するパルス状の電圧にて検出し、コア内に貫通配置
される被検出導線に流れる直流電流の絶対値の変化に対
応するこれらのパルス間隔を比較測定することにより、
該被検出導線に流れる直流電流の絶対値を検出する構成
からなるものである。In this DC current sensor, in the simplest configuration in which an exciting coil and a detecting coil are wound in a toroidal shape on a core made of an annular soft magnetic material, a magnetic field exceeding the coercive force of the core is generated in the exciting coil. Focusing on the fact that the direction of the magnetic flux in the core is reversed when a triangular waveform exciting current is passed, the timing of this reversal is detected by a pulse-like voltage generated in the detection coil, and is placed through the core. By comparing and measuring these pulse intervals corresponding to changes in the absolute value of the DC current flowing through the detected conductor,
It is configured to detect the absolute value of the DC current flowing through the detected conductor.
【０００５】[0005]
【発明が解決しようとする課題】本願出願人が先に提案
した上記の構成からなる直流電流センサーは、構造が比
較的簡単であり、比較的広範囲の電流変化に対しても直
線性に優れた検出能力を有する構造であるが、電気自動
車におけるバッテリーの充・放電量の管理用センサー等
では、バッテリー充電時の小電流から走行時の大電流ま
での非常に広い範囲（±４００Ａ程度）を精度良く測定
することが要求される。The DC current sensor having the above configuration proposed by the applicant of the present invention has a relatively simple structure and excellent linearity even in a relatively wide range of current change. Although it has a structure with detection capability, sensors for controlling the amount of charge / discharge of a battery in an electric vehicle, etc. can accurately cover a very wide range (about ± 400 A) from a small current when charging the battery to a large current when traveling. Good measurement is required.
【０００６】しかし、三角波状の励磁電流によって発生
するコア内の磁場と被検出導線に流れる直流電流によっ
て発生するコア内の磁場とが重畳され、これらの磁場に
よってコア内が飽和すると、コア内での磁場変化がなく
なり、結果として飽和している時間域では出力パルスが
得られず、三角波の山側又は谷側で発生するパルス間隔
の一方が非常に小さくなり、高感度の測定が困難とな
る。本願出願人の実験によれば、被検出導線に流れる直
流電流が２０Ａ程度を超えると、前記一方のパルス間隔
が実質的に零となり、目的とする電流測定の実現が困難
となっていた。However, when the magnetic field in the core generated by the triangular excitation current and the magnetic field in the core generated by the direct current flowing through the detected wire are superimposed, and when the core is saturated by these magnetic fields, the core becomes saturated. As a result, no output pulse is obtained in a time region in which the triangular wave is saturated, and one of the pulse intervals generated on the peak side or the valley side of the triangular wave becomes extremely small, and high-sensitivity measurement becomes difficult. According to the experiment conducted by the applicant of the present application, when the DC current flowing through the conductive wire to be detected exceeds about 20 A, the one pulse interval becomes substantially zero, and it has been difficult to achieve the intended current measurement.
【０００７】この発明は、上記のような現状に鑑み提案
するもので、先に本願出願人が提案した構成からなる直
流電流センサーが有する本来的な長所を損なうことな
く、特に、電気自動車等におけるバッテリーの充・放電
量の管理用センサーとして有効であり、小電流から大電
流までの広範囲の直流電流の測定が可能であるととも
に、被検出導線中を流れる交流電流をも重畳した状態で
測定可能とする電流センサーの提案を目的とするもので
ある。SUMMARY OF THE INVENTION The present invention is proposed in view of the above situation, and does not impair the inherent advantages of the DC current sensor having the configuration proposed by the applicant of the present invention. Effective as a sensor for managing the amount of charge / discharge of the battery, it can measure a wide range of DC current from small current to large current, and can also measure AC current flowing through the detected wire in a superimposed state The purpose of the present invention is to propose a current sensor.
【０００８】[0008]
【課題を解決するための手段】発明者は、上記の目的を
達成するために種々の構成を検討した結果、先に本願出
願人が提案した構成からなる直流電流センサーと基本的
な構成が同様である一対の直流電流センサーを効果的に
配置するとともに、フィードバックコイルを用いること
で、広範囲でも安定した直流電流の測定が可能となり、
さらに、交流電流センサーとしても環状軟質磁性材料を
用いた最も簡単な構成を採用することで、予想以上の効
果が得られることを確認した。As a result of studying various configurations to achieve the above object, the inventor has found that the basic configuration is the same as that of the DC current sensor having the configuration proposed by the applicant of the present invention. Along with effectively disposing a pair of DC current sensors and using a feedback coil, stable DC current measurement is possible over a wide range,
Furthermore, it was confirmed that the effect more than expected can be obtained by adopting the simplest configuration using the annular soft magnetic material also for the AC current sensor.
【０００９】すなわち、この発明は、励磁コイルをトロ
イダル状に巻回配置する一対の環状軟質磁性材料からな
る直流成分検出コアと、該一対の直流成分検出コアにま
たがって巻回配置する直流成分検出コイルと、環状軟質
磁性材料からなる交流成分検出コアと、前記一対の直流
成分検出コアと交流成分検出コアとにまたがって巻回配
置するフィードバックコイルとを有し、前記直流成分検
出コアと交流成分検出コアの内側に直流及び交流電流が
流れる被検出導線を貫通配置するとともに、前記一対の
直流成分検出コアに巻回配置する各々の励磁コイルを電
磁気的に逆相になるように接続し、各々の直流成分検出
コア内に該コアの保磁力を超える磁場を発生させる三角
波状の励磁電流を流すことによって発生する磁束と被検
出導線を流れる直流電流によって発生する磁束とに基づ
く直流成分検出コイルの出力を実質的に零とするフィー
ドバックコイルへの印加電流を測定するとともに、被検
出導線を流れる交流電流によって環状軟質磁性材料内に
発生する磁束に基づきフィードバックコイルに発生する
交流電流を測定することによって、被検出導線を流れる
直流及び交流電流を測定することを特徴とする電流セン
サーである。That is, the present invention provides a DC component detecting core made of a pair of annular soft magnetic materials in which an exciting coil is wound and disposed in a toroidal shape, and a DC component detecting coil which is wound and wound over the pair of DC component detecting cores. A coil, an AC component detection core made of an annular soft magnetic material, and a feedback coil wound and arranged over the pair of DC component detection cores and the AC component detection core, and the DC component detection core and the AC component are provided. Along with a detection target wire through which DC and AC currents flow through the inside of the detection core, the respective excitation coils wound around the pair of DC component detection cores are connected so as to be electromagnetically out of phase, A magnetic flux generated by flowing a triangular excitation current that generates a magnetic field exceeding the coercive force of the core in the DC component detection core of the DC component detection core and a direct current flowing through the conductor to be detected. Measure the applied current to the feedback coil that makes the output of the DC component detection coil substantially zero based on the magnetic flux generated by the current and the magnetic flux generated in the annular soft magnetic material by the AC current flowing through the detected wire. A current sensor for measuring a direct current and an alternating current flowing through a detected wire by measuring an alternating current generated in a feedback coil based on the current sensor.
【００１０】さらに、上記の構成において、環状軟質磁
性材料からなる交流成分検出コアが、一対の環状軟質磁
性材料からなる直流成分検出コアを介して、該直流成分
検出コアの両端側に一対配置した構成からなることを特
徴とする電流センサーを併せて提案する。Further, in the above configuration, a pair of AC component detecting cores made of an annular soft magnetic material are disposed at both ends of the DC component detecting core via a pair of DC component detecting cores made of an annular soft magnetic material. A current sensor characterized by having a configuration is also proposed.
【００１１】また、より好ましい構成として、励磁コイ
ルをトロイダル状に巻回配置する一対の環状軟質磁性材
料からなる直流成分検出コアと、該一対の直流成分検出
コアにまたがって巻回配置する直流成分検出コイルとを
シールドケース内に配置した構成からなることを特徴と
する電流センサーをも併せて提案する。Further, as a more preferable configuration, a DC component detecting core made of a pair of annular soft magnetic materials in which the excitation coil is wound in a toroidal shape, and a DC component wound and arranged over the pair of DC component detecting cores A current sensor characterized by a configuration in which a detection coil and a detection coil are arranged in a shield case is also proposed.
【００１２】[0012]
【発明の実施の形態】この発明の電流センサーにおい
て、一対の環状軟質磁性材料からなる直流成分検出コア
は、図示のような所謂リング状になっていることに限定
されるものではなく、その内側に直流電流及び交流電流
が流れる被検出導線を貫通配置でき、該軟質磁性材料が
電磁気的に閉回路を構成できるように接続されていれば
よく、加工性や励磁コイル等のコイル巻線の作業性等を
考慮して矩形枠状等を採用することもできる。DESCRIPTION OF THE PREFERRED EMBODIMENTS In a current sensor according to the present invention, a DC component detecting core made of a pair of annular soft magnetic materials is not limited to a so-called ring shape as shown in FIG. The soft magnetic material may be connected so that a closed circuit can be electromagnetically formed, and workability and work of coil windings such as an exciting coil can be performed. A rectangular frame shape or the like can be adopted in consideration of the properties and the like.
【００１３】直流成分検出コアを構成する軟質磁性材料
は、基本的に透磁率が高く保磁力が小さな材料が好まし
く、要求される検出感度に応じた磁気特性や、加工性等
を考慮して選定することが必要であり、Ｎｉ−Ｆｅ系合
金（パーマロイ）、ケイ素鋼鈑、アモルファス、電磁軟
鉄等の公知の軟質磁性合金材料の使用が好ましい。な
お、一対の直流成分検出コアは、高精度の測定を実現す
るには同一磁気特性、すなわち、同一材質、形状、寸法
を有する必要がある。The soft magnetic material constituting the DC component detecting core is preferably a material having a high magnetic permeability and a small coercive force. The soft magnetic material is selected in consideration of the magnetic characteristics according to the required detection sensitivity, workability, and the like. It is preferable to use a known soft magnetic alloy material such as a Ni—Fe alloy (permalloy), a silicon steel sheet, amorphous, or soft magnetic iron. Note that the pair of DC component detection cores need to have the same magnetic characteristics, that is, the same material, shape, and dimensions in order to achieve high-accuracy measurement.
【００１４】環状軟質磁性材料からなる交流成分検出コ
アは、交流磁気特性が良好な材料を選定することが望ま
しく、Ｍｎ−Ｚｎ系ソフトフェライト、Ｎｉ−Ｚｎ系ソ
フトフェライト、上記軟質磁性合金材料の積層体を用い
ることが望ましい。また、直流成分検出コアに巻回され
る各々励磁コイルの超磁力（アンペア・ターン）は、高
精度の測定を実現するには同一とする必要がある。For the AC component detecting core made of the annular soft magnetic material, it is desirable to select a material having good AC magnetic characteristics, and a Mn-Zn soft ferrite, a Ni-Zn soft ferrite, and a laminate of the above soft magnetic alloy material It is desirable to use the body. In addition, the supermagnetic force (ampere turn) of each exciting coil wound around the DC component detection core needs to be the same in order to realize high-accuracy measurement.
【００１５】この発明の電流センサーの作動原理を、図
１及び図２に基づいて説明する。図１において、１ａ，
１ｂはＮｉ−Ｆｅ系合金等の軟質磁性合金材料からなる
直流成分検出コアであり、２ａ，２ｂは各々直流成分検
出コア１ａ，１ｂに巻回配置される励磁コイルである。
なお、励磁コイル２ａ，２ｂは後述するようにして、各
々が電磁気的に逆相になるように接続される。３は、上
記一対の直流成分検出コアにまたがって巻回配置する直
流成分検出コイルである。The operation principle of the current sensor according to the present invention will be described with reference to FIGS. In FIG. 1, 1a,
Reference numeral 1b denotes a DC component detection core made of a soft magnetic alloy material such as a Ni-Fe alloy, and reference numerals 2a and 2b denote excitation coils wound around the DC component detection cores 1a and 1b, respectively.
The exciting coils 2a and 2b are connected so that they are electromagnetically opposite in phase as described later. Reference numeral 3 denotes a DC component detection coil that is wound around the pair of DC component detection cores.
【００１６】さらに、図１において、４は環状軟質磁性
材料からなる交流成分検出コアであり、前記一対の直流
成分検出コア１ａ，１ｂと該交流成分検出コア４とにま
たがってフィードバックコイル５が巻回配置されてい
る。このように構成した後、前記直流成分検出コア１
ａ，１ｂと交流成分検出コア４の内側に直流及び交流電
流が流れる被検出導線１０を貫通配置する。Further, in FIG. 1, reference numeral 4 denotes an AC component detection core made of an annular soft magnetic material, and a feedback coil 5 is wound over the pair of DC component detection cores 1a and 1b and the AC component detection core 4. Have been placed times. After the above configuration, the DC component detection core 1
Inside the a and 1b and the alternating current component detecting core 4, a detected conducting wire 10 through which a direct current and an alternating current flow is disposed so as to penetrate therethrough.
【００１７】このような構成において、被検出導線１０
を流れる直流電流Ｉを測定する動作原理を説明する。例
えば、被検出導線１０に直流電流Ｉが流れていない状態
にて、直流成分検出コア１ａに巻回配置される励磁コイ
ル２ａに、直流成分検出コア１ａの保磁力を超える磁場
を発生させる三角波状の励磁電流を流すと、直流成分検
出コア１ａ内には図２Ａの実線にて示す磁束が発生し、
その磁束変化に基づき直流成分検出コイル３に図２Ｂの
実線にて示す波形の出力が検出される。すなわち、出力
波形の幅寸法が同一となる（ｂ1＝ｂ2）。In such a configuration, the detected conductor 10
The principle of operation for measuring the direct current I flowing through the device will be described. For example, in a state where the DC current I does not flow through the detection target wire 10, a triangular wave shape that generates a magnetic field exceeding the coercive force of the DC component detection core 1 a in the excitation coil 2 a wound around the DC component detection core 1 a. 2A, a magnetic flux indicated by a solid line in FIG. 2A is generated in the DC component detection core 1a.
Based on the change in the magnetic flux, an output having a waveform indicated by a solid line in FIG. 2B is detected by the DC component detection coil 3. That is, the width dimensions of the output waveforms are the same (b 1 = b 2 ).
【００１８】ここで、被検出導線１０に直流電流Ｉが流
れると、直流成分検出コア１ａ内において、該直流電流
Ｉによって発生する磁場と前記励磁コイル２ａに印加さ
れる三角波状の励磁電流によって発生する磁場が重畳さ
れて一点鎖線位置までシフトし、図２Ａの破線にて示す
磁束が発生し、その磁束変化に基づき直流成分検出コイ
ル３に図２Ｃの破線にて示す波形の出力が検出される。
すなわち、幅寸法が＋側と−側とで異なる出力波形とな
る（ｃ1＜ｃ2）。Here, when the DC current I flows through the detected conductor 10, the DC component detection core 1a generates a magnetic field generated by the DC current I and a triangular excitation current applied to the excitation coil 2a. The magnetic field is superimposed and shifted to the position indicated by the dashed line, and a magnetic flux indicated by a broken line in FIG. 2A is generated. Based on the change in the magnetic flux, an output having a waveform indicated by the broken line in FIG. .
That is, the output waveforms have different width dimensions on the + side and the − side (c 1 <c 2 ).
【００１９】この出力波形に基づき＋側の出力波形と−
側の出力波形を積分・演算することにより、被検出導線
１０を流れる直流電流Ｉの向き（極性）とともに、電流
量を求めることができる。Based on this output waveform, the output waveform on the + side and-
By integrating and calculating the output waveform on the side, the direction (polarity) of the DC current I flowing through the detected conductor 10 and the current amount can be obtained.
【００２０】直流成分検出コア１ｂ、励磁コイル２ｂの
組み合わせにおいても、上記と同様な測定ができる。被
検出導線１０に流れる電流を高感度に測定するために
は、予め増幅度（ゲイン）を大きくしておく必要がある
が、これらを単独で用いると絶えず励磁コイル２ａまた
は２ｂからの励磁電流に基づく出力波形が検出コイル３
に出力されるため、その出力だけで飽和してしまい、増
幅度を大きくすることができない。With the combination of the DC component detecting core 1b and the exciting coil 2b, the same measurement as described above can be performed. In order to measure the current flowing through the detection target wire 10 with high sensitivity, it is necessary to increase the amplification degree (gain) in advance. However, if these are used alone, the excitation current from the excitation coil 2a or 2b is constantly reduced. The output waveform based on the detection coil 3
Therefore, the output alone saturates, and the amplification cannot be increased.
【００２１】本願出願人は、上記の問題を、これら各々
の励磁コイル２ａ，２ｂを電磁気的に逆相になるように
接続することで解消できることを確認した。すなわち、
検出導線１０に流れる電流が零の時には出力信号を零と
することによって、増幅度を大きくすることが可能とな
るのである。なお、励磁コイル２ａ，２ｂの巻き線方向
を互いに反対方向にするか、印加する三角波状の励磁電
流を逆相とする等の手段が採用できる。従って、被検出
導線１０に直流電流Ｉが流れていない状態では、図２Ｂ
における＋側、−側に全く反対の出力波形が出力される
こととなり、これらを合わせると実質的に検出コイルか
らの出力は零となる。The applicant of the present application has confirmed that the above problem can be solved by connecting the respective exciting coils 2a and 2b so as to be electromagnetically opposite in phase. That is,
By setting the output signal to zero when the current flowing through the detection conductor 10 is zero, the amplification degree can be increased. It is to be noted that the winding directions of the exciting coils 2a and 2b may be opposite to each other, or that the applied triangular exciting current may be reversed in phase. Therefore, in a state where the direct current I is not flowing through the detected conductor 10, FIG.
The output waveforms are completely opposite to the + side and the − side in the above, and when these are combined, the output from the detection coil becomes substantially zero.
【００２２】さらに、直流成分検出コア１ｂと励磁コイ
ル２ｂについて説明すると、上記の被検出導線１０に直
流電流Ｉが流れている状態にて励磁コイル２ｂを励磁コ
イル２ａに対して電磁気的に逆相になるように接続する
と、直流成分検出コア１ｂ内に図２Ａの二点鎖線にて示
す磁束が発生し、その磁束変化に基づき直流成分検出コ
イル３に図２Ｄの２点鎖線にて示す波形の出力が検出さ
れる。すなわち、幅寸法が＋側と−側とで異なる出力波
形となる（ｄ1＜ｄ2 ただし、ｃ1＝ｄ1、ｃ2＝ｄ2）。Further, the DC component detecting core 1b and the exciting coil 2b will be described. When the DC current I is flowing through the detected wire 10, the exciting coil 2b is electromagnetically opposite in phase to the exciting coil 2a. 2A, a magnetic flux indicated by a two-dot chain line in FIG. 2A is generated in the DC component detection core 1b, and the DC component detection coil 3 has a waveform having a waveform indicated by a two-dot chain line in FIG. Output is detected. That is, the output waveforms have different widths on the + side and the − side (d 1 <d 2 , where c 1 = d 1 and c 2 = d 2 ).
【００２３】従って、直流成分検出コイル３には、図２
Ｃの破線にて示す波形の出力と図２Ｄの２点鎖線にて示
す波形の出力との和が出力されることとなり、結果とし
て、図２Ｅの実線にて示す波形の出力が得られる。この
出力波形が＋側にあるか−側にあるかによって被検出導
線１０を流れる直流電流Ｉの向き（極性）が確認でき、
この出力波形の面積を求める、すなわち電気的に積分す
ることで被検出導線１０を流れる直流電流Ｉの電流量が
確認できる。Therefore, the DC component detecting coil 3 has the configuration shown in FIG.
The sum of the output of the waveform indicated by the broken line C and the output of the waveform indicated by the two-dot chain line in FIG. 2D is output, and as a result, the output of the waveform indicated by the solid line in FIG. 2E is obtained. The direction (polarity) of the DC current I flowing through the wire 10 to be detected can be confirmed depending on whether this output waveform is on the + side or the-side.
By calculating the area of the output waveform, that is, by electrically integrating the output waveform, the amount of the DC current I flowing through the detected conductor 10 can be confirmed.
【００２４】しかし、被検出導線１０を流れる直流電流
Ｉの絶対値が大きくなると、従来例でも説明したよう
に、三角波状の励磁電流によって発生するコア内の磁場
と被検出導線に流れる直流電流によって発生するコア内
の磁場とが重畳され、これらの磁場によってコア内が飽
和し、コア内での磁場変化がなくなり、結果として上記
のような出力波形を得ることができず、目的とする測定
が困難となる。However, when the absolute value of the DC current I flowing through the conductor 10 to be detected increases, as described in the conventional example, the magnetic field in the core generated by the triangular excitation current and the DC current flowing through the conductor to be detected. The generated magnetic field in the core is superimposed, the inside of the core is saturated by these magnetic fields, and the change in the magnetic field in the core disappears.As a result, the output waveform as described above cannot be obtained. It will be difficult.
【００２５】本願出願人は、さらに、上記の構成にて、
検出コイル３にて検出される出力が零になるまで、すな
わち、被検出導線１０を流れる直流電流Ｉに基づき直流
成分検出コア１ａ，１ｂ内に発生する磁束が零になるま
で該磁束を打ち消す方向の磁束を発生するようフィード
バックコイル５に所定の直流電流ｉを流し、その電流値
を測定することで、結果として被検出導線１０を流れる
直流電流Ｉの絶対値を知ることができる（ｉ＝Ｉ／Ｎｆ
Ｎｆ：フィードバックコイル５の卷数）ことを確認し
た。The applicant of the present application further has the above-mentioned configuration,
Direction until the output detected by the detection coil 3 becomes zero, that is, until the magnetic flux generated in the DC component detection cores 1a and 1b based on the DC current I flowing through the detected wire 10 becomes zero. A predetermined DC current i is caused to flow through the feedback coil 5 so as to generate the magnetic flux, and the current value is measured. As a result, the absolute value of the DC current I flowing through the conductor 10 to be detected can be known (i = I / Nf
Nf: number of turns of the feedback coil 5).
【００２６】上記のフィードバックコイル５を用いるこ
とによって、直流成分検出コア１ａ，１ｂ内に発生する
磁束が実質的に零の状態で測定を実施することから、直
流成分検出コア１ａ，１ｂの磁気的特性の最も安定した
領域を用いることとなり、小電流から大電流までの広範
囲において直線性に優れた測定を実現できることとな
る。By using the feedback coil 5, the measurement is performed with the magnetic flux generated in the DC component detection cores 1a and 1b being substantially zero, and therefore the magnetic components of the DC component detection cores 1a and 1b are Since the region having the most stable characteristics is used, measurement with excellent linearity can be realized in a wide range from a small current to a large current.
【００２７】以上に説明した被検出導線１０を流れる直
流電流Ｉを測定している際にも、被検出導線１０には交
流電流が流れている。しかし、交流電流が流れていても
該交流電流によって発生する各々の直流成分検出コア１
ａ、直流成分検出コア１ｂ、交流成分検出コア４内の磁
束に基づいてフィードバックコイル５に起電力が発生
し、所定の電流が流れる。該電流は前記各々の直流成分
検出コア１ａ、直流成分検出コア１ｂ、交流成分検出コ
ア４内の磁束を打ち消す方向の磁束を発生するため、実
質的に各々コア内の磁束はキャンセルされ、上記の直流
電流Ｉの測定に影響を及ぼさない。ただし、このような
作用効果を得るためには通常数１０００ターン以上のフ
ィードバックコイル５を巻回するのが望ましい。Even when the DC current I flowing through the detected conductor 10 described above is measured, an AC current is flowing through the detected conductor 10. However, even if an alternating current is flowing, each of the DC component detecting cores 1 generated by the alternating current.
a, an electromotive force is generated in the feedback coil 5 based on the magnetic flux in the DC component detection core 1b and the AC component detection core 4, and a predetermined current flows. Since the current generates a magnetic flux in a direction to cancel the magnetic flux in each of the DC component detecting core 1a, the DC component detecting core 1b, and the AC component detecting core 4, the magnetic flux in each core is substantially canceled, and It does not affect the measurement of the DC current I. However, it is usually desirable to wind the feedback coil 5 of several thousand turns or more in order to obtain such an effect.
【００２８】また、被検出導線１０を流れる交流電流に
ついては、該交流電流によって環状軟質磁性材料内に発
生する（交番）磁束に基づきフィードバックコイル５に
発生する交流電流を測定することによって電流波形を求
めることができる。The alternating current flowing through the conductive wire 10 to be detected is measured by measuring the alternating current generated in the feedback coil 5 based on the (alternating) magnetic flux generated in the annular soft magnetic material by the alternating current. You can ask.
【００２９】なお、フィードバックコイル５は先に説明
したように、被検出導線１０を流れる直流電流Ｉを測定
するために、所定の直流電流（帰還電流）を流しなが
ら、上記の交流電流の測定をも実施することとなるが、
直流電流Ｉ自体は帰還電流の値から求め、該帰還電流は
交流電流に対して零点をシフトするだけであり、交流電
流の電流波形を測定するには、なんら影響を及ぼさな
い。従って、フィードバックコイル５の出力波形を観察
することによって、被検出導線１０を流れる直流電流と
ともに交流電流とが重畳された状態での諸特性を測定す
ることが可能となる。As described above, the feedback coil 5 performs the above-described measurement of the AC current while flowing a predetermined DC current (feedback current) in order to measure the DC current I flowing through the wire 10 to be detected. Will also be implemented,
The DC current I itself is obtained from the value of the feedback current, which only shifts the zero point with respect to the AC current, and has no influence on the measurement of the current waveform of the AC current. Therefore, by observing the output waveform of the feedback coil 5, it is possible to measure various characteristics in a state where the DC current flowing through the detected conductor 10 and the AC current are superimposed.
【００３０】図１においては、環状軟質磁性材料からな
る交流成分検出コア４が、一対の環状軟質磁性材料から
なる直流成分検出コア１ａ，１ｂの一方端側にのみ配置
した構成を示したが、特に、一対の環状軟質磁性材料か
らなる直流成分検出コア１ａ，１ｂを介して、該直流成
分検出コア４の両端側に一対配置することによって、こ
れらのコア内を貫通する被検出導線１０とフィードバッ
クコイル５とが平行に配置されていない場合に発生する
磁束の不平衡による誤差を低減でき一層、安定した測定
を実現することができる。FIG. 1 shows a configuration in which an AC component detection core 4 made of an annular soft magnetic material is disposed only at one end of a pair of DC component detection cores 1a and 1b made of an annular soft magnetic material. In particular, by providing a pair of DC component detection cores 1a and 1b made of a pair of annular soft magnetic materials at both ends of the DC component detection core 4, the detected conductor 10 penetrating through these cores and the feedback conductor 10 are provided. Errors due to imbalance of magnetic flux generated when the coil 5 is not arranged in parallel can be reduced, and more stable measurement can be realized.
【００３１】また、環状軟質磁性材料からなる交流成分
検出コア４の配置は、被検出導線１０を流れる交流電流
の測定を可能とするだけでなく、いわゆる該コア４が電
流トランス（ＣＴ）と同様な機能を有することとなり、
周波数特性を改善し、電流センサー全体としての応答速
度を向上することにも寄与する。The arrangement of the AC component detecting core 4 made of a ring-shaped soft magnetic material not only enables the measurement of the AC current flowing through the conductive wire 10 to be detected, but also allows the core 4 to be similar to a current transformer (CT). Functions.
It also contributes to improving the frequency characteristics and improving the response speed of the current sensor as a whole.
【００３２】さらに、上記の構成において励磁コイル２
ａ，２ｂをトロイダル状に巻回配置する一対の環状軟質
磁性材料からなる直流成分検出コア１ａ，１ｂと、該一
対の直流成分検出コア１ａ，１ｂにまたがって巻回配置
する直流成分検出コイル３とをシールドケース内に配置
することによって、フィードバックコイル５によって発
生する本来の被検出導線１０を流れる直流電流Ｉに基づ
き直流成分検出コア１ａ，１ｂ内に発生する磁場を打ち
消す磁場以外の磁場による影響を低減することができ、
高精度の測定を実現するのに好ましい構成となる。Further, in the above configuration, the exciting coil 2
DC component detecting cores 1a and 1b made of a pair of annular soft magnetic materials in which a and 2b are wound in a toroidal shape, and DC component detecting coil 3 wound and disposed over the pair of DC component detecting cores 1a and 1b. Are arranged in the shield case, so that the magnetic field other than the magnetic field that cancels the magnetic field generated in the DC component detection cores 1a and 1b based on the DC current I that flows through the original detection target wire 10 and is generated by the feedback coil 5 Can be reduced,
This is a preferable configuration for realizing highly accurate measurement.
【００３３】[0033]
【実施例】この発明の効果を確認するために、図１に示
す電流センサーを作成した。直流成分検出コア１ａ，１
ｂは、それぞれ厚さ０．３５ｍｍのパーマロイＣ（７８
％Ｎｉ−５％Ｍｏ−４％Ｃｕ−ｂａｌＦｅ）を外径４５
ｍｍ、内径３３ｍｍに打ち抜き、所定の熱処理を施し
た。EXAMPLE In order to confirm the effect of the present invention, a current sensor shown in FIG. 1 was prepared. DC component detection cores 1a, 1
b is a 0.35 mm thick permalloy C (78
% Ni-5% Mo-4% Cu-balFe)
mm and an inner diameter of 33 mm, and was subjected to a predetermined heat treatment.
【００３４】さらに、これらの直流成分検出コア１ａ，
１ｂに電気的な絶縁を確保して、励磁コイル２ａ，２
ｂ、検出コイル３を巻回配置した。さらに、外径４５ｍ
ｍ、内径３３ｍｍ、厚さ５ｍｍからなるＭｎ−Ｚｎ系ソ
フトフェライトの交流成分検出コア４を直流成分検出コ
ア１ａ，１ｂとの電気的な絶縁を確保して一方端側に配
置した後、図示のように直流成分検出コア１ａ，１ｂ及
び交流成分検出コアをまたがるようにしてフィードバッ
クコイル５を巻回配置した。Further, these DC component detection cores 1a, 1a,
1b to ensure electrical insulation, and the excitation coils 2a, 2b
b, the detection coil 3 was wound and arranged. Furthermore, outside diameter 45m
After the AC component detection core 4 of Mn-Zn soft ferrite having an inner diameter of 33 mm and a thickness of 5 mm is arranged on one end side while ensuring electrical insulation from the DC component detection cores 1a and 1b, as shown in FIG. As described above, the feedback coil 5 is wound and disposed so as to straddle the DC component detection cores 1a and 1b and the AC component detection core.
【００３５】なお、励磁コイル２ａ，２ｂは、それぞれ
外径０．１２ｍｍのホルマル線１０００ターン巻回し、
検出コイル３は外径０．１２ｍｍのホルマル線を１００
０ターン巻回し、フィードバックコイル５は外径３．０
ｍｍのホルマル線を４０００ターン巻回した構成からな
る。The excitation coils 2a and 2b are each wound with a formal wire having an outer diameter of 0.12 mm for 1000 turns.
The detection coil 3 has a formal wire having an outer diameter of 0.12 mm
0 turns, the feedback coil 5 has an outer diameter of 3.0
It consists of a formal wire having a length of 4,000 turns.
【００３６】直流成分検出コア１ａ，１ｂ及び交流成分
検出コア４の内側に外径１６ｍｍのビニル被覆からなる
被検出導線１０を貫通配置するとともに、先に直流成分
検出コア１ａ，１ｂに独立して巻回配置した励磁コイル
２ａ，２ｂを所定の方法にて電磁気的に逆相になるよう
に接続し、これらの励磁コイル、検出コイル、及びフィ
ードバックコイルを所定の電子回路を接続して、本発明
の電流センサーを完成した。なお、励磁コイル２ａ，２
ｂに印加する三角波状の励磁電流はｆ＝４ｋＨｚ、Ｉｐ
＝±１５ｍＡとした。A conductive wire 10 made of vinyl coating having an outer diameter of 16 mm is penetrated inside the direct current component detecting cores 1a and 1b and the alternating current component detecting core 4, and is independent of the direct current component detecting cores 1a and 1b. The excitation coils 2a and 2b wound and connected are connected in a predetermined manner so as to be electromagnetically opposite in phase, and the excitation coil, the detection coil, and the feedback coil are connected to a predetermined electronic circuit. Completed the current sensor. Note that the exciting coils 2a, 2
The excitation current having a triangular waveform applied to b is f = 4 kHz, Ip
= ± 15 mA.
【００３７】ここで、被検出導線１０に±４００Ａの範
囲で直流電流を流した場合の、この発明の電流センサー
における入・出力特性を図３に示す。図３より広範囲で
リニアの特性が得られることが確認できた。FIG. 3 shows the input / output characteristics of the current sensor according to the present invention when a direct current is applied to the detected conductor 10 in a range of ± 400 A. It was confirmed from FIG. 3 that linear characteristics were obtained over a wide range.
【００３８】図４は、被検出導線１０に所定交流電流
を、５００ｍＡｒｍｓ、１Ａｒｍｓ、５Ａｒｍｓ、１０
Ａｒｍｓ、２０Ａｒｍｓ流した時の、この発明の電流セ
ンサーにおける周波数特性を示すものであり、図中、ａ
は５００ｍＡｒｍｓ、ｂは１Ａｒｍｓ、ｃは５Ａｒｍ
ｓ、ｄは１０Ａｒｍｓ、ｅは２０Ａｒｍｓを示す。図４
より、周波数の変動によっても出力変動が少ないことが
確認できた。FIG. 4 shows that a predetermined alternating current is applied to the detected conductor 10 by 500 m Arms, 1 Arms, 5 Arms, 10 Arms,
FIG. 10 shows frequency characteristics of the current sensor of the present invention when Arms and 20 Arms are flown.
Is 500 Arms, b is 1 Arms, c is 5 Arms
s and d indicate 10 Arms, and e indicates 20 Arms. FIG.
Thus, it was confirmed that the output fluctuation was small even by the frequency fluctuation.
【００３９】図５Ｂは、被検出導線１０に所定の周波数
からなる矩形状（１ｋＨｚ、１Ａｐ−ｐ）を流した時の
フィードバックコイル出力端の電圧を示す。図５より被
検出導線に流した電流と同一の変化がフィードバックコ
イル出力電圧として表れていることが確認できた。従っ
て、被検出導線の流れる電流に応じて同様な出力が追従
性良く表れることが明らかとなった。FIG. 5B shows the voltage at the output terminal of the feedback coil when a rectangular shape (1 kHz, 1 Ap-p) having a predetermined frequency is passed through the conductive wire 10 to be detected. From FIG. 5, it was confirmed that the same change as the current flowing through the detected wire appeared as the feedback coil output voltage. Therefore, it has been clarified that a similar output appears with good followability in accordance with the current flowing through the detected conductor.
【００４０】[0040]
【発明の効果】以上に示すように、この発明の電流セン
サーにおいては、本願出願人が先に提案した構成からな
る直流電流センサーとともに、交流成分検出コア、フィ
ードバックコイルを効果的に配置することによって、構
造が比較的簡単であり、広範囲の電流変化に対しても直
線性に優れた検出能力を有する、すなわち、±０．１Ａ
〜４００Ａ程度の範囲までを測定可能とした構造であ
り、電気自動車におけるバッテリーの充・放電量の管理
用センサー等に有効な電流センサーの提供を実現するも
のである。As described above, in the current sensor of the present invention, the AC component detection core and the feedback coil are effectively arranged together with the DC current sensor having the configuration proposed by the applicant of the present invention. Has a relatively simple structure and has excellent linearity detection capability even in a wide range of current change, that is, ± 0.1 A
It has a structure capable of measuring a range up to about 400 A, and realizes the provision of a current sensor that is effective as a sensor for managing the charge / discharge amount of a battery in an electric vehicle.
【図１】この発明の直流電流センサーの構成を示す斜視
説明図である。FIG. 1 is an explanatory perspective view showing a configuration of a DC current sensor of the present invention.
【図２】Ａは直流成分検出コア内に発生する磁束を示す
グラフ、Ｂ，Ｃ，Ｄは直流成分検出コイルに発生する出
力を示すグラフ、ＥはＣとＤと合算した直流成分検出コ
イルに得られる出力を示すグラフである。FIG. 2A is a graph showing a magnetic flux generated in a DC component detection core, B, C, and D are graphs showing outputs generated in a DC component detection coil, and E is a graph showing a DC component detection coil obtained by adding C and D. 5 is a graph showing the output obtained.
【図３】被測定電流と出力電流との関係を示すグラフで
ある。FIG. 3 is a graph showing a relationship between a measured current and an output current.
【図４】被測定電流の周波数と出力変動との関係を示す
グラフであり、ａは５００ｍＡｒｍｓ、ｂは１Ａｒｍ
ｓ、ｃは５Ａｒｍｓ、ｄは１０Ａｒｍｓ、ｅは２０Ａｒ
ｍｓの場合を示すFIG. 4 is a graph showing the relationship between the frequency of a measured current and output fluctuation, wherein a is 500 mArms, and b is 1 Arm.
s and c are 5 Arms, d is 10 Arms, e is 20 Ars
ms
【図５】Ａは被検出導線に流れる貫通電流の応答波形、
Ｂはフィードバックコイルの出力電圧の応答波形を示す
グラフである。FIG. 5A is a response waveform of a through current flowing through a detected wire,
B is a graph showing a response waveform of the output voltage of the feedback coil.
１ａ，１ｂ 直流成分検出コア ２ａ，２ｂ 励磁コイル ３ 直流成分検出コイル ４ 交流成分検出コア ５ フィードバックコイル １０ 被検出導線 1a, 1b DC component detection core 2a, 2b Excitation coil 3 DC component detection coil 4 AC component detection core 5 Feedback coil 10 Detected conductor
Claims (3)
る一対の環状軟質磁性材料からなる直流成分検出コア
と、該一対の直流成分検出コアにまたがって巻回配置す
る直流成分検出コイルと、環状軟質磁性材料からなる交
流成分検出コアと、前記一対の直流成分検出コアと交流
成分検出コアとにまたがって巻回配置するフィードバッ
クコイルとを有し、前記直流成分検出コアと交流成分検
出コアの内側に直流及び交流電流が流れる被検出導線を
貫通配置するとともに、前記一対の直流成分検出コアに
巻回配置する各々の励磁コイルを電磁気的に逆相になる
ように接続し、各々の直流成分検出コア内に該コアの保
磁力を超える磁場を発生させる三角波状の励磁電流を流
すことによって発生する磁束と被検出導線を流れる直流
電流によって発生する磁束とに基づく直流成分検出コイ
ルの出力を実質的に零とするフィードバックコイルへの
印加電流を測定するとともに、被検出導線を流れる交流
電流によって環状軟質磁性材料内に発生する磁束に基づ
きフィードバックコイルに発生する交流電流を測定する
ことによって、被検出導線を流れる直流及び交流電流を
測定することを特徴とする電流センサー。A DC component detecting core formed of a pair of annular soft magnetic materials in which an exciting coil is wound in a toroidal shape; a DC component detecting coil wound and disposed over the pair of DC component detecting cores; An AC component detection core made of a soft magnetic material, and a feedback coil wound and disposed over the pair of DC component detection cores and the AC component detection core, inside the DC component detection core and the AC component detection core And a plurality of excitation coils wound around the pair of DC component detection cores are connected so as to be electromagnetically opposite in phase, and each DC component is detected. It is generated by a magnetic flux generated by flowing a triangular wave-like exciting current that generates a magnetic field exceeding the coercive force of the core and a DC current flowing through the detected wire. Measure the applied current to the feedback coil that makes the output of the DC component detection coil based on the magnetic flux substantially zero, and apply the feedback coil based on the magnetic flux generated in the annular soft magnetic material by the AC current flowing through the detected wire. A current sensor for measuring a direct current and an alternating current flowing through a detected wire by measuring an generated alternating current.
らなる交流成分検出コアが、一対の環状軟質磁性材料か
らなる直流成分検出コアを介して、該直流成分検出コア
の両端側に一対配置した構成からなることを特徴とする
電流センサー。2. The device according to claim 1, wherein a pair of AC component detection cores made of an annular soft magnetic material are disposed at both ends of the DC component detection core via a pair of DC component detection cores made of an annular soft magnetic material. A current sensor comprising a configuration.
ダル状に巻回配置する一対の環状軟質磁性材料からなる
直流成分検出コアと、該一対の直流成分検出コアにまた
がって巻回配置する直流成分検出コイルとをシールドケ
ース内に配置した構成からなることを特徴とする電流セ
ンサー。3. A DC component detecting core formed of a pair of annular soft magnetic materials in which an exciting coil is wound and disposed in a toroidal shape, and a DC component wound and disposed over the pair of DC component detecting cores according to claim 1. A current sensor comprising a configuration in which a detection coil and a detection coil are arranged in a shield case.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9157852A JPH10332745A (en) | 1997-05-29 | 1997-05-29 | Electric current sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP9157852A JPH10332745A (en) | 1997-05-29 | 1997-05-29 | Electric current sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH10332745A true JPH10332745A (en) | 1998-12-18 |
Family
ID=15658788
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP9157852A Pending JPH10332745A (en) | 1997-05-29 | 1997-05-29 | Electric current sensor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH10332745A (en) |
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006300583A (en) * | 2005-04-18 | 2006-11-02 | Nec Lighting Ltd | Discharge lamp current measuring device |
| US7218092B2 (en) | 2002-06-18 | 2007-05-15 | Loyal Port Company Limited | Magnetic bridge type current sensor, magnetic bridge type current detecting method, and magnetic bridge for use in that sensor and detecting method |
| JP2008519269A (en) * | 2004-11-05 | 2008-06-05 | ダンフィシク アクティーゼルスカブ | Detection circuit for current measurement |
| WO2010041340A1 (en) | 2008-10-10 | 2010-04-15 | 有限会社ワイワイオフィス | Magnetic bridge for sensor using magnetic fluid, and current sensor and magnetic sensor using the magnetic bridge |
| WO2014080609A1 (en) * | 2012-11-21 | 2014-05-30 | パナソニック株式会社 | Current detecting device |
| JP2015068725A (en) * | 2013-09-30 | 2015-04-13 | 東日本旅客鉄道株式会社 | Current detector and substation facility including the same |
| JP2015533424A (en) * | 2012-10-31 | 2015-11-24 | リ，サンチョル | Fluxgate non-contact current measuring instrument |
| KR102274949B1 (en) * | 2020-01-09 | 2021-07-07 | 공주대학교 산학협력단 | Electromagnetic coil system having a triangular structure |
| JP2021530683A (en) * | 2018-07-02 | 2021-11-11 | フルークコーポレイションFluke Corporation | Current transformer |
-
1997
- 1997-05-29 JP JP9157852A patent/JPH10332745A/en active Pending
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7218092B2 (en) | 2002-06-18 | 2007-05-15 | Loyal Port Company Limited | Magnetic bridge type current sensor, magnetic bridge type current detecting method, and magnetic bridge for use in that sensor and detecting method |
| JP2008519269A (en) * | 2004-11-05 | 2008-06-05 | ダンフィシク アクティーゼルスカブ | Detection circuit for current measurement |
| JP4842275B2 (en) * | 2004-11-05 | 2011-12-21 | リエゾン エレクトロニク・メカニク レム ソシエテ アノニム | Detection circuit for current measurement |
| JP2006300583A (en) * | 2005-04-18 | 2006-11-02 | Nec Lighting Ltd | Discharge lamp current measuring device |
| WO2010041340A1 (en) | 2008-10-10 | 2010-04-15 | 有限会社ワイワイオフィス | Magnetic bridge for sensor using magnetic fluid, and current sensor and magnetic sensor using the magnetic bridge |
| JP2015533424A (en) * | 2012-10-31 | 2015-11-24 | リ，サンチョル | Fluxgate non-contact current measuring instrument |
| WO2014080609A1 (en) * | 2012-11-21 | 2014-05-30 | パナソニック株式会社 | Current detecting device |
| JP2014122879A (en) * | 2012-11-21 | 2014-07-03 | Panasonic Corp | Current detector |
| US9841442B2 (en) | 2012-11-21 | 2017-12-12 | Panasonic Intellectual Property Management Co., Ltd. | Current detecting device |
| JP2015068725A (en) * | 2013-09-30 | 2015-04-13 | 東日本旅客鉄道株式会社 | Current detector and substation facility including the same |
| JP2021530683A (en) * | 2018-07-02 | 2021-11-11 | フルークコーポレイションFluke Corporation | Current transformer |
| KR102274949B1 (en) * | 2020-01-09 | 2021-07-07 | 공주대학교 산학협력단 | Electromagnetic coil system having a triangular structure |
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