JP4873348B2

JP4873348B2 - Current sensor and current detection device

Info

Publication number: JP4873348B2
Application number: JP2007114827A
Authority: JP
Inventors: 信幸新地; 章岡田
Original assignee: Kohshin Electric Corp
Current assignee: Kohshin Electric Corp
Priority date: 2007-03-27
Filing date: 2007-03-27
Publication date: 2012-02-08
Anticipated expiration: 2027-03-27
Also published as: JP2008241678A

Description

この発明は、被測定電流が印加される一次導体のＵ字型形状部の近傍において、被測定電流を測定する電流センサおよび電流検出装置に関するものである。 The present invention relates to a current sensor and a current detection device that measure a current to be measured in the vicinity of a U-shaped portion of a primary conductor to which the current to be measured is applied.

従来の電流センサあるいは磁気センサとして、複数の磁気抵抗効果素子からなるブリッジ回路を、絶縁体を介して所定の間隔を離してＵ字型の一次導体に配置したものがある（例えば、特許文献１参照）。 As a conventional current sensor or magnetic sensor, there is one in which a bridge circuit composed of a plurality of magnetoresistive elements is arranged on a U-shaped primary conductor via an insulator with a predetermined interval (for example, Patent Document 1). reference).

特開平８−２１１１３８公報 Japanese Patent Laid-Open No. 8-21138

上記特許文献１に開示されている電流センサまたは磁気センサの一次導体は、左右対称的なＵ字型構造で、磁気抵抗効果素子で構成するブリッジ回路の左右の各ハーフブリッジに逆方向磁界が印加され、一様な外部磁界を除去する利点がある。また上記特許文献では一次導体から絶縁体を介して所定の間隔を離してブリッジ回路を配置する構成をとっており、小容量測定の場合はプリント基板のような絶縁体の一面に一次導体を設置した構成でも、一次導体を含めた電流センサとしての寸法がそれほど大型化することはない。しかしながら、小容量と同一の磁気抵抗効果素子（同一のブリッジ回路）を用いて大電流を測定する場合、小容量の場合と同程度の磁束密度を磁気抵抗効果素子に印加する必要があるため、Ｕ字型構造を構成する左右の一次導体を離間するとともに、一次導体から磁気抵抗効果素子をある程度離して設置しなければならず、一次導体を含めた電流センサとしての寸法が大型化するという問題点があった。 The primary conductor of the current sensor or magnetic sensor disclosed in Patent Document 1 has a symmetrical U-shaped structure, and a reverse magnetic field is applied to each of the left and right half bridges of a bridge circuit composed of magnetoresistive elements. And has the advantage of removing a uniform external magnetic field. In the above-mentioned patent document, the bridge circuit is arranged at a predetermined distance from the primary conductor through the insulator. In the case of small capacity measurement, the primary conductor is installed on one surface of the insulator such as a printed circuit board. Even with this configuration, the size of the current sensor including the primary conductor does not increase so much. However, when measuring a large current using the same magnetoresistive effect element (same bridge circuit) as the small capacity, it is necessary to apply a magnetic flux density of the same level as that of the small capacity to the magnetoresistive effect element. The left and right primary conductors constituting the U-shaped structure must be separated from each other, and the magnetoresistive effect element must be installed to some extent away from the primary conductor, resulting in an increase in the size of the current sensor including the primary conductor. There was a point.

この発明は上記のような課題を解決するためになされたもので、一様な外部磁界を除去すると共に、大電流の測定が可能な、小型かつ測定レンジを拡大した電流センサを得ることを目的とする。また、多相電流の検出時に他相電流の影響を低減し、より正確な電流を検出できる電流検出装置を得ることを目的とする。 The present invention has been made to solve the above-described problems, and an object of the present invention is to obtain a small-sized current sensor with an expanded measurement range capable of removing a uniform external magnetic field and measuring a large current. And Another object of the present invention is to obtain a current detection device that can detect the current more accurately by reducing the influence of the other-phase current when detecting the multiphase current.

この発明に係る電流センサは、設置基板上に４つの磁気抵抗効果素子で、設置基板の中心線に対して分けられた一方の領域に第１のハーフブリッジ回路が配置されると共に、他方の領域に第２のハーフブリッジ回路が配置された電流検知デバイス部と、少なくとも１つのＵ字型形状部を有する一次導体で構成され、上記電流検知デバイスがＵ字型形状を形成して上記一次導体に囲まれた空間内の少なくとも一箇所に、上記設置基板の中心線とＵ字型形状の対称軸が略一致するように配置されるようにしたものである。 The current sensor according to the present invention includes four magnetoresistive elements on the installation board, the first half bridge circuit is arranged in one area separated from the center line of the installation board, and the other area. And a primary conductor having at least one U-shaped portion, and the current detecting device forms a U-shape to form the primary conductor. The center line of the installation board and the U-shaped symmetry axis are arranged so as to substantially coincide with each other in at least one place in the enclosed space.

以上のように、この発明によれば、設置基板上に４つの磁気抵抗効果素子で、設置基板の中心線に対して分けられた一方の領域に第１のハーフブリッジ回路が配置されると共に、他方の領域に第２のハーフブリッジ回路が配置され、それぞれのハーフブリッジ回路に逆方向の磁界が印加される構造のため、一様な外部磁界を除去する効果がある。
また、電流検知デバイス部がＵ字型形状を形成した一次導体に囲まれた空間内の少なくとも一箇所に設置され、一次導体に発生する磁界の主たる方向と異なる方向に磁気抵抗効果素子の感磁方向を配置する構造としたため、小型で大電流の測定が可能となる。
さらにまた、１つのＵ字型形状の一次導体に囲まれた空間内に異なる磁束密度が生じるため、同じ特性の電流検知デバイス部を複数個設置して、小型で、かつ測定レンジを拡大できる効果がある。もしくは１つの一次導体に設置した複数のＵ字型形状の、一次導体に囲まれたそれぞれの空間内に、少なくとも１つの同じ特性の電流検知デバイス部を設置して、小型で、かつ測定レンジを拡大できる効果がある。また、複数の一次導体を略平行になるように並列設置したため、多相の電流検出時に他相の電流により発生する磁界の影響を受けず、より正確に電流検出できる効果がある。As described above, according to the present invention, the first half-bridge circuit is arranged in one region divided with respect to the center line of the installation board by four magnetoresistive elements on the installation board, Since the second half bridge circuit is arranged in the other region and a magnetic field in the opposite direction is applied to each half bridge circuit, there is an effect of removing a uniform external magnetic field.
In addition, the current sensing device is installed in at least one place in the space surrounded by the U-shaped primary conductor, and the magnetoresistive element is sensitive to a direction different from the main direction of the magnetic field generated in the primary conductor. Due to the structure in which the directions are arranged, it is possible to measure a large current with a small size.
Furthermore, since different magnetic flux densities are generated in a space surrounded by a single U-shaped primary conductor, a plurality of current sensing device parts having the same characteristics can be installed to reduce the size and extend the measurement range. There is. Alternatively, at least one current detection device unit having the same characteristics is installed in each space surrounded by the primary conductors in a plurality of U-shapes installed on one primary conductor, so that the measurement range is small. There is an effect that can be expanded. Further, since the plurality of primary conductors are arranged in parallel so as to be substantially parallel, there is an effect that current detection can be performed more accurately without being affected by the magnetic field generated by the current of the other phase at the time of detecting the multiphase current.

実施の形態１．
図１は、この発明の実施の形態１による電流センサの斜視図を示すもので、図２は図１の平面図、図３は図１または図２におけるＡＡ断面（ＸＺ面）の一部を示す断面図である。図において、電流センサ１は、電流検知デバイス部６、センサ回路部７を有するセンサ基板２と、一次導体３により構成される。
本実施の形態１では、一次導体３は長手方向に向かって略垂直に曲げ加工が施されて１つのＵ字形状部５を形成し、Ｕ字形状部５内の一次導体に囲まれた空間部１０に１つの電流検知デバイス部６を配置する。
まず、電流検知デバイス部６の構成について説明する。
図５は電流検知デバイス部６の平面図を示すもので、設置基板１５上において、設置基板１５の中心線９によって２つの領域に分けられ、それぞれの領域に磁気抵抗効果素子１２ａ、１２ｂ、磁気抵抗効果素子１２ｃ、１２ｄが線対称に等しく配置される。ここで、磁気抵抗効果素子１２の感磁方向はＸ方向とする。４つの磁気抵抗効果素子１２ａ〜１２ｄは、設置基板１５の中心線９に対して相互に平行方向に配置され、磁気抵抗効果素子１２ａ、１２ｄは、互いに逆方向の磁界の増加に応じて抵抗値が共に増加する磁気抵抗効果特性を有するように、また、磁気抵抗効果素子１２ｂ、１２ｃは、互いに逆方向の磁界の増加に応じて抵抗値が共に減少する磁気抵抗効果特性を有するように、図には省略したが、磁気抵抗効果素子上にはバーバーポール電極構造が形成されている。なお、４つの磁気抵抗効果素子１２はそれぞれ１本で構成したが、クランク形状に複数の磁気抵抗効果素子を接続し、線路長を長く構成してもよい。また、中心線９上の中心点に対して点対称に構成してもよい。接続電流線１３は、４つの磁気抵抗効果素子１２間を接続することにより、ブリッジ回路１６を構成するものであり、接続エリア１４は、外部とブリッジ回路１６の入出力用の端子部として用いる。Embodiment 1 FIG.
1 is a perspective view of a current sensor according to Embodiment 1 of the present invention, FIG. 2 is a plan view of FIG. 1, and FIG. 3 is a partial AA cross section (XZ plane) in FIG. 1 or FIG. It is sectional drawing shown. In the figure, the current sensor 1 includes a sensor substrate 2 having a current detection device unit 6 and a sensor circuit unit 7, and a primary conductor 3.
In the first embodiment, the primary conductor 3 is bent substantially perpendicularly in the longitudinal direction to form one U-shaped portion 5, and the space surrounded by the primary conductor in the U-shaped portion 5. One current detection device unit 6 is arranged in the unit 10.
First, the configuration of the current detection device unit 6 will be described.
FIG. 5 shows a plan view of the current detection device unit 6, which is divided into two regions on the installation substrate 15 by the center line 9 of the installation substrate 15, and the magnetoresistive effect elements 12 a, 12 b, Resistive effect elements 12c and 12d are arranged equally in line symmetry. Here, the magnetic sensing direction of the magnetoresistive effect element 12 is the X direction. The four magnetoresistive effect elements 12a to 12d are arranged in parallel to each other with respect to the center line 9 of the installation substrate 15, and the magnetoresistive effect elements 12a and 12d have a resistance value corresponding to an increase in the magnetic field in the opposite direction. The magnetoresistive effect elements 12b and 12c have a magnetoresistive effect characteristic in which the resistance value decreases together with an increase in the magnetic field in the opposite direction. Although not shown, a barber pole electrode structure is formed on the magnetoresistive element. The four magnetoresistive effect elements 12 are each configured as one, but a plurality of magnetoresistive effect elements may be connected in a crank shape to increase the line length. Further, it may be configured symmetrically with respect to the center point on the center line 9. The connection current line 13 forms a bridge circuit 16 by connecting the four magnetoresistive effect elements 12, and the connection area 14 is used as an input / output terminal portion of the bridge circuit 16.

図６はこの発明の実施の形態１による電流センサ１の電流検知デバイス部６を示す構成概略図であり、図６において、４つの磁気抵抗効果素子１２間を接続電流線１３で接続することにより、磁気抵抗効果素子１２ａ、１２ｂの直列接続からなるハーフブリッジ回路（第１のハーフブリッジ回路）１７ａと、磁気抵抗効果素子１２ｃ、１２ｄの直列接続からなるハーフブリッジ回路（第２のハーフブリッジ回路）１７ｂとの並列接続からなるブリッジ回路１６を構成するものである。
接続エリア（第１の接続エリア）１４ａは、ブリッジ回路１６の磁気抵抗効果素子１２ａ、１２ｃ間の接続電流線１３に接続され、もう一方の接続エリア（第２の接続エリア）１４ｂは、ブリッジ回路１６の磁気抵抗効果素子１２ｂ、１２ｄ間の接続電流線１３に接続されており、接続エリア１４ａ、１４ｂからブリッジ回路１６に電圧が供給されるものである。接続エリア（第３の接続エリア）１４ｃは、ブリッジ回路１６の磁気抵抗効果素子１２ａ、１２ｂ間の接続電流線１３に接続され、もう一方の接続エリア（第４の接続エリア）１４ｄは、ブリッジ回路１６の磁気抵抗効果素子１２ｃ、１２ｄ間の接続電流線１３に接続されており、接続エリア１４ｃ、１４ｄからブリッジ回路１６の出力電圧が検出されるものである。FIG. 6 is a schematic configuration diagram showing the current detection device unit 6 of the current sensor 1 according to the first embodiment of the present invention. In FIG. 6, the four magnetoresistive elements 12 are connected by the connection current line 13. A half bridge circuit (first half bridge circuit) 17a composed of series connection of magnetoresistive effect elements 12a and 12b, and a half bridge circuit (second half bridge circuit) composed of series connection of magnetoresistive effect elements 12c and 12d The bridge circuit 16 is formed by parallel connection with 17b.
The connection area (first connection area) 14a is connected to the connection current line 13 between the magnetoresistive effect elements 12a and 12c of the bridge circuit 16, and the other connection area (second connection area) 14b is the bridge circuit. The magnetoresistive effect elements 12b and 12d are connected to a connection current line 13, and a voltage is supplied to the bridge circuit 16 from the connection areas 14a and 14b. The connection area (third connection area) 14c is connected to the connection current line 13 between the magnetoresistive effect elements 12a and 12b of the bridge circuit 16, and the other connection area (fourth connection area) 14d is the bridge circuit. It is connected to the connection current line 13 between the 16 magnetoresistive effect elements 12c and 12d, and the output voltage of the bridge circuit 16 is detected from the connection areas 14c and 14d.

なお、図５および図６には示していないが、設置基板１５上の４つの磁気抵抗効果素子１２ａ〜１２ｄの上方、または下方、またはその両方に絶縁層を介して補償導電線１８を配置し、ブリッジ回路１６の出力電圧に基づいて、それらの補償導電線１８に４つの磁気抵抗効果素子１２の近傍に発生する磁界を打ち消すような電流を供給する磁気補償型の構成としてもよい。 Although not shown in FIGS. 5 and 6, the compensation conductive line 18 is disposed above or below the four magnetoresistive elements 12 a to 12 d on the installation substrate 15, or both via an insulating layer. A magnetic compensation type configuration may be employed in which a current that cancels out the magnetic field generated in the vicinity of the four magnetoresistive elements 12 is supplied to the compensation conductive lines 18 based on the output voltage of the bridge circuit 16.

次に、電流センサ１の全体構成について説明する。
図１に示すように、被測定電流を印加する一次導体３の一部には、長手方向に向かって略垂直に曲げ加工が施され、Ｚ方向から見てＵ字の形状となるように１つのＵ字形状部５が形成される。なお本実施の形態１に示した図では、Ｕ字形状の底部の両脇部分が直角形状に構成されているが、電流検知デバイス部６に両側のＵ字部形成一次導体４から安定して逆方向の磁界が印加される構造であれば丸みを帯びた形状などでもよく、これに限るものではないが、安定して逆方向の磁界を印加するためにはＵ字形状が少なくとも電流検知デバイス部６の近傍において左右対称であることが望ましい。
図２に示すように、Ｕ字形状部５の対称軸、および電流検知デバイス部６の中心線９が略一致するようにセンサ基板２はＵ字形状部５の下面に設置されている。本実施の形態においては、センサ基板２をＵ字形状部５の下面に設置した例を示したが、設置位置は下面に限るものではない。
空間部１０内の電流検知デバイス部６の設置位置（特にＺ方向）は、磁気抵抗効果素子１２に付与したい磁界、つまりは被測定電流の大きさに応じて決定するが、Ｚ方向における１次導体３の中央となる位置（図３破線Ｏ）では感磁方向の付与磁界が０となるため、中央からずらして設置するのがよい。また、一次導体３の断面積は、印加する被測定電流値の大きさに応じて決定される。このような一次導体３は、例えば銅などの金属による直線状導体バー形状から、Ｕ字形状部５の曲げ加工等により作製される。
センサ基板２上には、電流検知デバイス部６とともにセンサ回路部７を配置する。センサ回路部７は、電流検知デバイス部６の接続エリア１４ａ、１４ｂにブリッジ回路１６の電圧を供給すると共に、ブリッジ回路１６の出力電圧を適度な増幅を施して出力するが、電流センサ１の外部への入出力には、外部端子８を利用する。
センサ基板２と１次導体３は、特に図示しないが接着剤や取付部材等を用いて固定する。取付部材は特に材料を限定しないが、非磁性で経時劣化の少ないものが望ましく、絶縁性や耐圧の効果を上げるために全体、あるいは一部を樹脂モールドしてもよい。Next, the overall configuration of the current sensor 1 will be described.
As shown in FIG. 1, a part of the primary conductor 3 to which the current to be measured is applied is bent substantially perpendicularly in the longitudinal direction, so that it is U-shaped when viewed from the Z direction. Two U-shaped portions 5 are formed. In the figure shown in the first embodiment, both side portions of the U-shaped bottom portion are formed in a right-angle shape. However, the current detection device portion 6 is stably provided with U-shaped portion forming primary conductors 4 on both sides. As long as it has a structure to which a magnetic field in the reverse direction is applied, it may have a rounded shape or the like, but is not limited to this, but in order to stably apply a magnetic field in the reverse direction, the U-shape is at least a current detection device. In the vicinity of the portion 6, it is desirable that it is bilaterally symmetrical.
As shown in FIG. 2, the sensor substrate 2 is installed on the lower surface of the U-shaped part 5 so that the symmetry axis of the U-shaped part 5 and the center line 9 of the current detection device part 6 substantially coincide. In the present embodiment, an example in which the sensor substrate 2 is installed on the lower surface of the U-shaped portion 5 is shown, but the installation position is not limited to the lower surface.
The installation position (especially in the Z direction) of the current detection device unit 6 in the space 10 is determined according to the magnetic field to be applied to the magnetoresistive element 12, that is, the magnitude of the current to be measured. Since the applied magnetic field in the magnetosensitive direction is 0 at the position that is the center of the conductor 3 (broken line O in FIG. 3), it is preferable that the conductor 3 be installed shifted from the center. The cross-sectional area of the primary conductor 3 is determined according to the magnitude of the measured current value to be applied. Such a primary conductor 3 is produced from a linear conductor bar shape made of a metal such as copper, for example, by bending the U-shaped portion 5 or the like.
On the sensor substrate 2, the sensor circuit unit 7 is arranged together with the current detection device unit 6. The sensor circuit unit 7 supplies the voltage of the bridge circuit 16 to the connection areas 14a and 14b of the current detection device unit 6 and outputs the output voltage of the bridge circuit 16 with appropriate amplification. An external terminal 8 is used for input / output to / from.
The sensor substrate 2 and the primary conductor 3 are fixed using an adhesive, a mounting member or the like, although not particularly shown. The mounting member is not particularly limited in material, but is preferably non-magnetic and less deteriorated with time, and may be entirely or partially resin-molded in order to increase the effect of insulation and pressure resistance.

次に、電流センサ１の動作について、図３、図４、図５により説明する。
一次導体３に被測定電流を印加すると、例えば第１のＵ字部形成一次導体４ａには電流の方向に対して図３の破線に示すように左回転の磁界が、また第２のＵ字部形成一次導体４ｂには電流の方向に対して図３の破線に示すように右回転の磁界が、印加される被測定電流の大きさに応じて発生する。図には簡単のために各１次導体あたり２本の磁束線によって発生磁界を示した。その結果、電流検知デバイス部６を空間部１０の下面近傍に設置した場合、電流検知デバイス部６の右側に位置する磁気抵抗効果素子１２ｃ、１２ｄには、図４（ａ）に示す磁界ベクトル１１が印加され、磁気抵抗効果素子１２ｃ、１２ｄの感磁方向（Ｘ方向）には分解ベクトル１１ａが加わることになる。それぞれの分解ベクトルの大きさは、１１ａ＜１１ｂの関係が成立するため、Ｘ方向とＺ方向で比較した場合、Ｚ方向の１１ｂが主たる磁界の方向となる。つまり、電流検知デバイス部６のＸＹ面における、図５に示した磁気抵抗効果素子１２ａ、１２ｂには、中心線９より紙面左側の向きに磁界が加わり、磁気抵抗効果素子１２ｃ、１２ｄには、中心線９より紙面右側の向きに磁界が加わる。
一方、特許文献１に示されるように電流検知デバイス部６ａを空間部１０の外に設置した場合、電流検知デバイス部６ａの右側に位置する磁気抵抗効果素子１２ｃ、１２ｄには、図４（ｂ）に示す磁界ベクトル１１が印加され、磁気抵抗効果素子１２ｃ、１２ｄの感磁方向（Ｘ方向）には分解ベクトル１１ｃが加わることになる。それぞれの分解ベクトルの大きさは、１１ｄ＜１１ｃの関係が成立するため、Ｘ方向とＺ方向で比較した場合、Ｘ方向の１１ｃが主たる磁界の方向となる。ここで図４（ａ）に示す磁界ベクトル１１と図４（ｂ）に示す磁界ベクトル１１は大きさがほぼ等しく方向の異なるベクトルであり、図のようにそれぞれの感磁方向の分解ベクトルの大きさは、１１ａ＜１１ｃの関係が成立する。Next, the operation of the current sensor 1 will be described with reference to FIGS. 3, 4, and 5.
When a current to be measured is applied to the primary conductor 3, for example, the first U-shaped primary conductor 4a has a left-rotating magnetic field as shown by a broken line in FIG. In the part-forming primary conductor 4b, a clockwise magnetic field is generated according to the magnitude of the current to be measured, as shown by the broken line in FIG. For the sake of simplicity, the generated magnetic field is shown by two magnetic flux lines for each primary conductor. As a result, when the current detection device unit 6 is installed in the vicinity of the lower surface of the space unit 10, the magnetoresistive effect elements 12c and 12d positioned on the right side of the current detection device unit 6 have a magnetic field vector 11 shown in FIG. Is applied to the magnetoresistive effect elements 12c and 12d in the magnetosensitive direction (X direction). Since the relationship of 11a <11b holds for the magnitudes of the respective decomposition vectors, when compared in the X direction and the Z direction, 11b in the Z direction is the main magnetic field direction. That is, a magnetic field is applied to the magnetoresistive effect elements 12a and 12b shown in FIG. 5 on the XY plane of the current detection device unit 6 in the direction of the left side of the drawing with respect to the center line 9, and the magnetoresistive effect elements 12c and 12d have A magnetic field is applied in the direction of the right side of the drawing from the center line 9.
On the other hand, when the current detection device unit 6a is installed outside the space portion 10 as shown in Patent Document 1, the magnetoresistive effect elements 12c and 12d positioned on the right side of the current detection device unit 6a are shown in FIG. ) Is applied, and the decomposition vector 11c is added in the magnetosensitive direction (X direction) of the magnetoresistive elements 12c and 12d. Since the relationship of 11d <11c holds for the magnitudes of the respective decomposition vectors, when compared in the X direction and the Z direction, 11c in the X direction is the main magnetic field direction. Here, the magnetic field vector 11 shown in FIG. 4 (a) and the magnetic field vector 11 shown in FIG. 4 (b) are vectors having substantially the same magnitude and different directions. That is, the relationship of 11a <11c is established.

このように、図３に示す電流検知デバイス部６の位置では、一次導体に近い位置であるにもかかわらず、それぞれの磁気抵抗効果素子１２の感磁方向には、主たる方向と異なる方向の低められた磁界が印加されることになる。そのため、被測定電流が大電流であっても磁気抵抗効果素子１２に印加される磁界が抑制され、出力の飽和などを気にすることなく、かつ電流センサとしての外形寸法を大型化することなく、大電流の計測が容易に行える。
なお、磁気抵抗効果素子１２ａ、１２ｄでは、共に磁界の増加に応じて抵抗値が増加すると共に、磁界の減少に応じて抵抗値が減少する磁気抵抗効果特性を有するように、また、磁気抵抗効果素子１２ｂ、１２ｃでは、逆に磁界の増加に応じて抵抗値が減少すると共に、磁界の減少に応じて抵抗値が増加する磁気抵抗効果特性を有するように構成されている。
よって、一次導体３に流れる電流の増加に応じて磁気抵抗効果素子１２ａ、１２ｄの抵抗値が増加すると共に、磁気抵抗効果素子１２ｂ、１２ｃの抵抗値が減少し、一次導体３に流れる電流の減少に応じて磁気抵抗効果素子１２ａ、１２ｄの抵抗値が減少すると共に、磁気抵抗効果素子１２ｂ、１２ｃの抵抗値が増加する。このように、一次導体３に印加される被測定電流の大きさに応じてブリッジ回路１６の平衡が崩れ、これが電流検知デバイス部６のブリッジ回路１６の出力となる。As described above, in the position of the current detection device unit 6 shown in FIG. 3, although the position is close to the primary conductor, the magnetosensitive effect direction of each magnetoresistive effect element 12 is lower in the direction different from the main direction. The applied magnetic field is applied. Therefore, even if the current to be measured is a large current, the magnetic field applied to the magnetoresistive effect element 12 is suppressed, without worrying about output saturation, etc., and without increasing the external dimensions of the current sensor. , Large current can be easily measured.
The magnetoresistive elements 12a and 12d both have a magnetoresistive effect characteristic in which the resistance value increases as the magnetic field increases and the resistance value decreases as the magnetic field decreases. In contrast, the elements 12b and 12c are configured to have a magnetoresistive effect characteristic in which the resistance value decreases as the magnetic field increases and the resistance value increases as the magnetic field decreases.
Therefore, as the current flowing through the primary conductor 3 increases, the resistance values of the magnetoresistive elements 12a and 12d increase, and the resistance values of the magnetoresistive elements 12b and 12c decrease, and the current flowing through the primary conductor 3 decreases. Accordingly, the resistance values of the magnetoresistive effect elements 12a and 12d are decreased, and the resistance values of the magnetoresistive effect elements 12b and 12c are increased. Thus, the balance of the bridge circuit 16 is lost in accordance with the magnitude of the current to be measured applied to the primary conductor 3, and this becomes the output of the bridge circuit 16 of the current detection device unit 6.

さらに、電流センサ１の動作について、補償導電線１８を有する場合について説明する。補償導電線１８を配置した電流検知デバイス部６とセンサ回路部７の概略構成を図７に示す。
一次導体３に印加される被測定電流の大きさに応じてブリッジ回路１６の平衡が崩れる。このとき、センサ回路部７に設置された増幅回路部（例えばオペアンプ１９）では、電流検知デバイス部６の接続エリア１４ｃ、１４ｄから検出される出力電圧に基づいて、磁気抵抗効果素子１２ａ〜１２ｄ近傍に発生する磁界を打ち消すような電流（制御電流）を補償導電線１８に供給する。具体的には接続エリア１４ｃ、１４ｄの出力電圧が０になるように、制御電流の大きさを調整する。補償導電線１８は、その制御電流の大きさに応じて４つの磁気抵抗効果素子１２ａ〜１２ｄ近傍に発生する磁界、すなわち一次導体３に印加される被測定電流の大きさに応じた磁界を相殺するような磁界を発生する。
したがって、一次導体３に印加される被測定電流の大きさに応じたブリッジ回路１６の平衡の崩れを、センサ回路部７から供給される制御電流により修復することができる。ゆえに、センサ回路部７から供給した制御電流の大きさが、一次導体３に印加される被測定電流の大きさに相関のある値として検出することができる。
なお、一次導体３以外において発生させた外部磁界（外乱磁界）は、磁気抵抗効果素子１２ａ、１２ｂと磁気抵抗効果素子１２ｃ、１２ｄ（ブリッジ回路１６の左右の各ハーフブリッジ回路１７）に同相の影響となるため相殺され、測定精度に影響を与えない。Further, the operation of the current sensor 1 will be described in the case where the compensation conductive line 18 is provided. FIG. 7 shows a schematic configuration of the current detection device unit 6 and the sensor circuit unit 7 in which the compensation conductive line 18 is arranged.
The bridge circuit 16 is unbalanced according to the magnitude of the current to be measured applied to the primary conductor 3. At this time, in the amplification circuit unit (for example, the operational amplifier 19) installed in the sensor circuit unit 7, the vicinity of the magnetoresistive effect elements 12a to 12d based on the output voltage detected from the connection areas 14c and 14d of the current detection device unit 6. A current (control current) that cancels the generated magnetic field is supplied to the compensation conductive line 18. Specifically, the magnitude of the control current is adjusted so that the output voltage of the connection areas 14c and 14d becomes zero. The compensation conductive line 18 cancels out the magnetic field generated in the vicinity of the four magnetoresistive elements 12a to 12d according to the magnitude of the control current, that is, the magnetic field according to the magnitude of the current to be measured applied to the primary conductor 3. Generate a magnetic field.
Therefore, the collapse of the balance of the bridge circuit 16 according to the magnitude of the current to be measured applied to the primary conductor 3 can be repaired by the control current supplied from the sensor circuit unit 7. Therefore, the magnitude of the control current supplied from the sensor circuit unit 7 can be detected as a value correlated with the magnitude of the current to be measured applied to the primary conductor 3.
The external magnetic field (disturbance magnetic field) generated outside the primary conductor 3 has the same effect on the magnetoresistive effect elements 12a and 12b and the magnetoresistive effect elements 12c and 12d (the left and right half bridge circuits 17 of the bridge circuit 16). Therefore, it is offset and does not affect the measurement accuracy.

以上のように、この実施の形態１によれば、設置基板上に４つの磁気抵抗効果素子で、設置基板の中心線に対して分けられた一方の領域に第１のハーフブリッジ回路が配置されると共に、他方の領域に第２のハーフブリッジ回路が配置され、それぞれのハーフブリッジ回路に逆方向の磁界が印加される構造のため、一様な外部磁界を除去することができる。 As described above, according to the first embodiment, the first half-bridge circuit is arranged in one region divided with respect to the center line of the installation board by four magnetoresistive elements on the installation board. In addition, since the second half bridge circuit is arranged in the other region and a magnetic field in the opposite direction is applied to each half bridge circuit, a uniform external magnetic field can be removed.

また、磁気抵抗効果素子の感磁方向への印加磁界を抑制する構成としたため、大電流の測定が容易に可能となり、さらに電流検知デバイス部６を空間部１０内に設置したため、一次導体を含めた電流センサの構造が小型となる効果がある。 In addition, since the magnetic field applied in the magnetosensitive direction of the magnetoresistive effect element is suppressed, it is possible to easily measure a large current. Further, since the current detection device unit 6 is installed in the space 10, the primary conductor is included. In addition, there is an effect that the structure of the current sensor is reduced in size.

実施の形態２．
図８は、この発明の実施の形態２による電流センサのＡＡ断面（ＸＺ面）の一部を示す断面図である。本実施の形態２は、図１に示した電流センサ１のＵ字形状部５における空間部１０に、電流検知デバイス部６に加えてさらに第２の電流検知デバイス部６ｂを設置したものである。図には省略したが、第２の電流検知デバイス部６ｂは、電流検知デバイス部６と同様にセンサ回路部とともにセンサ基板に設置されるものとする。
実施の形態２は、実施の形態１に新たに電流検知デバイス部６ｂを付加した構成であり、その他の構成で重複する部分は省略する。実施の形態２は、一次導体３の空間部１０において、印加した被測定電流に応じて発生する磁界を２箇所で計測するようにしたものである。Embodiment 2. FIG.
FIG. 8 is a cross-sectional view showing a part of the AA cross section (XZ plane) of the current sensor according to Embodiment 2 of the present invention. In the second embodiment, in addition to the current detection device unit 6, a second current detection device unit 6 b is further installed in the space 10 in the U-shaped unit 5 of the current sensor 1 shown in FIG. 1. . Although not shown in the drawing, the second current detection device unit 6b is installed on the sensor substrate together with the sensor circuit unit in the same manner as the current detection device unit 6.
The second embodiment is a configuration in which a current detection device unit 6b is newly added to the first embodiment, and the overlapping portions in other configurations are omitted. In the second embodiment, in the space 10 of the primary conductor 3, the magnetic field generated according to the applied current to be measured is measured at two locations.

実施の形態２における電流センサ１の全体構成について説明する。
Ｕ字形状部５の対称軸、および電流検知デバイス部６の中心線９が略一致するように電流検知デバイス部６は空間部１０内の端部近傍に設置され、かつＵ字形状部５の対称軸、および第２の電流検知デバイス部６ｂの中心線９が略一致するように第２の電流検知デバイス部６ｂは空間部１０内の電流検知デバイス部６に比較してＺ方向の中央よりに設置される。２つの電流検知デバイス部６、６ｂの設置位置（特にＺ方向）は、磁気抵抗効果素子１２に付与したい磁界に応じて決定する。
各電流検知デバイス部における磁気抵抗効果素子等の構成は実施の形態１に示した電流検知デバイス部６と同一構成とし、重複を避けるため記述しない。
それぞれのセンサ回路部は、それぞれの電流検知デバイス部の接続エリア１４ａ、１４ｂにブリッジ回路１６の電圧を供給すると共に、ブリッジ回路１６の出力電圧を適度な増幅を施して出力するが、異なる部分の磁界を計測するため、増幅率等の各センサ回路部の構成は異なる場合がある。
なお、本実施の形態においては、各電流検知デバイス部を空間部１０の下側に設置した例を示したが、空間部１０の上側に設置してもよく、あるいは２つに限ったものではなくさらに複数個設置してもよい。The overall configuration of the current sensor 1 in the second embodiment will be described.
The current detection device unit 6 is installed near the end in the space 10 so that the symmetry axis of the U-shaped unit 5 and the center line 9 of the current detection device unit 6 substantially coincide with each other. Compared with the current detection device unit 6 in the space 10, the second current detection device unit 6 b is closer to the center in the Z direction so that the axis of symmetry and the center line 9 of the second current detection device unit 6 b substantially coincide. Installed. The installation positions (particularly in the Z direction) of the two current detection device units 6 and 6b are determined according to the magnetic field to be applied to the magnetoresistive effect element 12.
The configuration of the magnetoresistive effect element and the like in each current detection device unit is the same as that of the current detection device unit 6 shown in the first embodiment, and is not described in order to avoid duplication.
Each sensor circuit unit supplies the voltage of the bridge circuit 16 to the connection areas 14a and 14b of the respective current detection device units and outputs the output voltage of the bridge circuit 16 with appropriate amplification. In order to measure a magnetic field, the configuration of each sensor circuit unit such as an amplification factor may be different.
In the present embodiment, the example in which each current detection device unit is installed on the lower side of the space unit 10 is shown. However, the current detection device unit may be installed on the upper side of the space unit 10, or the current detection device unit is not limited to two. There may be more than one.

次に、実施の形態２における電流センサ１の動作について、図８により説明する。
一次導体３に被測定電流を印加すると、例えば第１のＵ字部形成一次導体４ａには電流の方向に対して図８の破線に示すように左回転の磁界が、また第２のＵ字部形成一次導体４ｂには電流の方向に対して図８の破線に示すように右回転の磁界が、印加される被測定電流の大きさに応じて発生する。図には簡単のために各１次導体あたり２本の磁束線によって発生磁界を示した。その結果、電流検知デバイス部６を空間部１０の下面近傍に設置した場合、電流検知デバイス部６の右側に位置する磁気抵抗効果素子１２ｃ、１２ｄには、図９（ａ）に示す磁界ベクトル１１が印加され、磁気抵抗効果素子１２ｃ、１２ｄの感磁方向（Ｘ方向）には分解ベクトル１１ａが加わることになる。それぞれの分解ベクトルの大きさは、１１ａ＜１１ｂの関係が成立するため、Ｘ方向とＺ方向で比較した場合、Ｚ方向の１１ｂが主たる磁界の方向となる。つまり、電流検知デバイス部６のＸＹ面における、図５に示した磁気抵抗効果素子１２ａ、１２ｂには、中心線９より紙面左側の向きに磁界が加わり、磁気抵抗効果素子１２ｃ、１２ｄには、中心線９より紙面右側の向きに磁界が加わる。
第２の電流検知デバイス部６ｂを空間部１０内の電流検知デバイス部６に比較してＺ方向の中央よりに設置した場合、電流検知デバイス部６ｂの右側に位置する磁気抵抗効果素子１２ｃ、１２ｄには、図９（ｂ）に示す磁界ベクトル１１が印加され、磁気抵抗効果素子１２ｃ、１２ｄの感磁方向（Ｘ方向）には分解ベクトル１１ｃが加わることになる。それぞれの分解ベクトルの大きさは、１１ｃ＜１１ｄの関係が成立するため、Ｘ方向とＺ方向で比較した場合、Ｚ方向の１１ｄが主たる磁界の方向となる。ここで図９（ａ）に示す磁界ベクトル１１と図９（ｂ）に示す磁界ベクトル１１は方向の異なるベクトルであり、図のようにそれぞれの感磁方向の分解ベクトルの大きさは、１１ｃ＜１１ａの関係が成立する。Next, the operation of the current sensor 1 in the second embodiment will be described with reference to FIG.
When a current to be measured is applied to the primary conductor 3, for example, the first U-shaped primary conductor 4a has a left-rotating magnetic field as shown by a broken line in FIG. In the part-forming primary conductor 4b, a clockwise magnetic field is generated according to the magnitude of the current to be measured as shown by the broken line in FIG. For the sake of simplicity, the generated magnetic field is shown by two magnetic flux lines for each primary conductor. As a result, when the current detection device unit 6 is installed in the vicinity of the lower surface of the space unit 10, the magnetoresistive effect elements 12 c and 12 d located on the right side of the current detection device unit 6 include the magnetic field vector 11 shown in FIG. Is applied to the magnetoresistive effect elements 12c and 12d in the magnetosensitive direction (X direction). Since the relationship of 11a <11b holds for the magnitudes of the respective decomposition vectors, when compared in the X direction and the Z direction, 11b in the Z direction is the main magnetic field direction. That is, a magnetic field is applied to the magnetoresistive effect elements 12a and 12b shown in FIG. 5 on the XY plane of the current detection device unit 6 in the direction of the left side of the drawing with respect to the center line 9, and the magnetoresistive effect elements 12c and 12d have A magnetic field is applied in the direction of the right side of the drawing from the center line 9.
When the second current detection device unit 6b is installed from the center in the Z direction as compared with the current detection device unit 6 in the space 10, the magnetoresistive effect elements 12c and 12d located on the right side of the current detection device unit 6b. Is applied with the magnetic field vector 11 shown in FIG. 9B, and the decomposition vector 11c is added in the magnetosensitive direction (X direction) of the magnetoresistive effect elements 12c and 12d. Since the relationship of 11c <11d is established for the magnitudes of the respective decomposition vectors, 11d in the Z direction is the main magnetic field direction when compared in the X direction and the Z direction. Here, the magnetic field vector 11 shown in FIG. 9 (a) and the magnetic field vector 11 shown in FIG. 9 (b) are vectors having different directions, and the magnitude of the decomposition vector in each magnetic sensitive direction is 11c < 11a is established.

このように、図８に示す電流検知デバイス部６ならびに第２電流検知デバイス部６ｂの位置では、一次導体に近い位置であるにもかかわらず、それぞれの磁気抵抗効果素子１２の感磁方向には、主たる方向と異なる方向の低められた磁界が印加されることになる。そのため、被測定電流が大電流であっても磁気抵抗効果素子１２に印加される磁界が抑制され、出力の飽和などを気にすることなく、かつ電流センサとしての外形寸法を大型化することなく、大電流の計測が容易に行える。かつ、電流検知デバイス部６と第２電流検知デバイス部６ｂの位置で比較すると、より中央に近い第２電流検知デバイス部６ｂの位置で、より低められた磁界が印加されることになる。
つまり、第２の電流検知デバイス部６ｂの位置では、被測定電流が大電流であっても磁気抵抗効果素子１２に印加される磁界がさらに抑制され、出力の飽和などを気にすることなく、かつ電流センサとしての外形寸法を大型化することなく、大電流の計測が容易に行え、電流検知デバイス部６の位置では、被測定電流がやや小容量の電流になっても磁気抵抗効果素子１２に印加される磁界の抑制度は小さく、出力の低下によるＳ／Ｎの悪化などを気にすることなく、やや小容量の電流の計測が容易に行える。
例えば、各電流検知デバイス部６、６ｂのハーフブリッジ部分（例えば１７ｂ）に被測定電流値に対して付与される磁界は、図１０のように示され、やや小容量の電流の計測時は電流検知デバイス部６、大電流の測定時は電流検知デバイス部６ｂを利用するように構成すれば、同じ特性の電流検知デバイス部を用いても、各センサ回路部の増幅率等の若干の調整で、図１１に示すように測定レンジの拡大した精度の良い電流センサを構築することが可能となる。As described above, in the positions of the current detection device unit 6 and the second current detection device unit 6b shown in FIG. A lowered magnetic field in a direction different from the main direction is applied. Therefore, even if the current to be measured is a large current, the magnetic field applied to the magnetoresistive effect element 12 is suppressed, without worrying about output saturation, etc., and without increasing the external dimensions of the current sensor. , Large current can be easily measured. In addition, when compared at the positions of the current detection device unit 6 and the second current detection device unit 6b, a lower magnetic field is applied at the position of the second current detection device unit 6b closer to the center.
That is, at the position of the second current detection device unit 6b, even if the current to be measured is a large current, the magnetic field applied to the magnetoresistive effect element 12 is further suppressed without worrying about output saturation, In addition, a large current can be easily measured without increasing the outer dimensions of the current sensor, and the magnetoresistive effect element 12 can be measured at the position of the current detection device section 6 even if the current to be measured becomes a small capacity current. The degree of suppression of the magnetic field applied to the capacitor is small, and it is possible to easily measure a slightly small current without worrying about the deterioration of S / N due to a decrease in output.
For example, the magnetic field applied to the current value to be measured in the half-bridge portion (for example, 17b) of each of the current detection device units 6 and 6b is shown in FIG. 10, and the current is measured when measuring a slightly small current. If the detection device unit 6 is configured to use the current detection device unit 6b when measuring a large current, even if a current detection device unit having the same characteristics is used, the amplification factor of each sensor circuit unit can be slightly adjusted. As shown in FIG. 11, it is possible to construct an accurate current sensor with an expanded measurement range.

なお、実施の形態１と同様に、磁気抵抗効果素子１２ａ、１２ｄでは、共に磁界の増加に応じて抵抗値が増加すると共に、磁界の減少に応じて抵抗値が減少する磁気抵抗効果特性を有するように、また、磁気抵抗効果素子１２ｂ、１２ｃでは、逆に磁界の増加に応じて抵抗値が減少すると共に、磁界の減少に応じて抵抗値が増加する磁気抵抗効果特性を有するように構成されているため、一次導体３に流れる電流の増加に応じて磁気抵抗効果素子１２ａ、１２ｄの抵抗値が増加すると共に、磁気抵抗効果素子１２ｂ、１２ｃの抵抗値が減少し、一次導体３に流れる電流の減少に応じて磁気抵抗効果素子１２ａ、１２ｄの抵抗値が減少すると共に、磁気抵抗効果素子１２ｂ、１２ｃの抵抗値が増加する。このように、一次導体３に印加される被測定電流の大きさに応じてブリッジ回路１６の平衡が崩れ、これが各電流検知デバイス部６、６ｂのブリッジ回路１６の出力となる。 As in the first embodiment, the magnetoresistive effect elements 12a and 12d both have a magnetoresistive effect characteristic in which the resistance value increases as the magnetic field increases and the resistance value decreases as the magnetic field decreases. Similarly, the magnetoresistive effect elements 12b and 12c are configured to have a magnetoresistive effect characteristic in which the resistance value decreases as the magnetic field increases and the resistance value increases as the magnetic field decreases. Therefore, as the current flowing through the primary conductor 3 increases, the resistance values of the magnetoresistive elements 12a and 12d increase, and the resistance values of the magnetoresistive elements 12b and 12c decrease, so that the current flowing through the primary conductor 3 As the resistance decreases, the resistance values of the magnetoresistive effect elements 12a and 12d decrease and the resistance values of the magnetoresistive effect elements 12b and 12c increase. Thus, the balance of the bridge circuit 16 is lost in accordance with the magnitude of the current to be measured applied to the primary conductor 3, and this becomes the output of the bridge circuit 16 of each of the current detection device sections 6 and 6b.

以上のように、この実施の形態２によれば、設置基板上に４つの磁気抵抗効果素子で、設置基板の中心線に対して分けられた一方の領域に第１のハーフブリッジ回路が配置されると共に、他方の領域に第２のハーフブリッジ回路が配置され、それぞれのハーフブリッジ回路に逆方向の磁界が印加される構造のため、一様な外部磁界を除去することができる。 As described above, according to the second embodiment, the first half-bridge circuit is arranged in one region divided with respect to the center line of the installation board by four magnetoresistive elements on the installation board. In addition, since the second half bridge circuit is arranged in the other region and a magnetic field in the opposite direction is applied to each half bridge circuit, a uniform external magnetic field can be removed.

また、磁気抵抗効果素子の感磁方向への印加磁界を抑制する構成としたため、大電流の測定が容易に可能となり、さらに電流検知デバイス部６、６ｂを空間部１０内に設置したため、一次導体を含めた電流センサの構造が小型となる効果がある。
また、一次導体の空間部１０内に異なる磁束密度が生じる構造のため、同じ特性の電流検知デバイス部を複数個設置して、小型で、かつ測定レンジを精度良く拡大できる効果がある。さらにまた、同じ特性の電流検知デバイス部が利用できるため、複数の異なる特性の電流検知デバイス部を用意する必要がなく、低コスト化となる効果がある。In addition, since the configuration in which the magnetic field applied in the magnetosensitive direction of the magnetoresistive effect element is suppressed, a large current can be easily measured, and the current detection device portions 6 and 6b are installed in the space portion 10, so that the primary conductor There is an effect that the structure of the current sensor including is reduced in size.
In addition, since different magnetic flux densities are generated in the space portion 10 of the primary conductor, there is an effect that a plurality of current detection device portions having the same characteristics can be installed, and the measurement range can be accurately expanded. Furthermore, since the current detection device portions having the same characteristics can be used, it is not necessary to prepare a plurality of current detection device portions having different characteristics, and the cost can be reduced.

実施の形態３．
図１２は、この発明の実施の形態３による電流センサの平面図を示すもので、図１３は図１２のＡＡ断面（ＸＺ面）の一部を示す断面図である。本実施の形態３では、一次導体３は長手方向に向かって略垂直に曲げ加工が施され、幅の異なる２つのＵ字形状部５、５ａを形成し、Ｕ字形状部５、５ａ内である一次導体に囲まれた空間部１０、１０ａのそれぞれに１つの電流検知デバイス部６、６ｃを配置し、それぞれにおいて、印加した被測定電流に応じて発生する磁界を計測するようにしたものである。
実施の形態３は、実施の形態１に新たにＵ字形状部５ａおよび電流検知デバイス部６ｃを付加した構成であり、その他の構成で重複する部分は省略する。Embodiment 3 FIG.
12 is a plan view of a current sensor according to Embodiment 3 of the present invention, and FIG. 13 is a cross-sectional view showing a part of the AA cross section (XZ plane) of FIG. In the third embodiment, the primary conductor 3 is bent substantially vertically in the longitudinal direction to form two U-shaped portions 5 and 5a having different widths. One current detection device section 6 and 6c is arranged in each of the space sections 10 and 10a surrounded by a certain primary conductor, and in each of them, a magnetic field generated according to an applied current to be measured is measured. is there.
The third embodiment is a configuration in which a U-shaped portion 5a and a current detection device portion 6c are newly added to the first embodiment, and overlapping portions in other configurations are omitted.

実施の形態３における電流センサ１の全体構成について説明する。
Ｕ字形状部５の対称軸、および電流検知デバイス部６の中心線９が略一致するように電流検知デバイス部６は空間部１０内の下面近傍に設置され、かつＵ字形状部５ａの対称軸、および第２の電流検知デバイス部６ｃの中心線９が略一致するように第２の電流検知デバイス部６ｃは空間部１０ａ内の下面近傍に設置される。２つの電流検知デバイス部６、６ｃの設置位置（特にＺ方向）は、磁気抵抗効果素子１２に付与したい磁界に応じて決定する。本実施の形態においては、同一のセンサ基板２上に２つの電流検知デバイス部を配置したため、各電流検知デバイス部のＹ方向、Ｚ方向の位置は同一構成であるが、これに限るものでなく、異なる座標軸上に設置するために別のセンサ基板に配置してもよい。
各電流検知デバイス部における磁気抵抗効果素子等の構成は実施の形態１に示した電流検知デバイス部６と同一構成とし、重複を避けるため記述しない。
それぞれのセンサ回路部は、それぞれの電流検知デバイス部の接続エリア１４ａ、１４ｂにブリッジ回路１６の電圧を供給すると共に、ブリッジ回路１６の出力電圧を適度な増幅を施して出力するが、異なる部分の磁界を計測するため、増幅率等の各センサ回路部の構成は異なる場合がある。
なお、本実施の形態においては、各電流検知デバイス部を空間部１０、１０ａの下側に設置した例を示したが、空間部１０、１０ａの上側や中央以外の内部に設置してもよく、あるいは２つに限ったものではなくさらに複数個設置してもよい。The overall configuration of the current sensor 1 in the third embodiment will be described.
The current detection device unit 6 is installed near the lower surface in the space 10 so that the symmetry axis of the U-shaped unit 5 and the center line 9 of the current detection device unit 6 substantially coincide with each other, and the U-shaped unit 5a is symmetrical. The second current detection device portion 6c is installed in the vicinity of the lower surface in the space portion 10a so that the axis and the center line 9 of the second current detection device portion 6c substantially coincide. The installation positions (particularly in the Z direction) of the two current detection device units 6 and 6c are determined according to the magnetic field to be applied to the magnetoresistive effect element 12. In the present embodiment, since two current detection device units are arranged on the same sensor substrate 2, the positions of the current detection device units in the Y direction and the Z direction are the same, but the present invention is not limited to this. It may be arranged on a separate sensor board for installation on different coordinate axes.
The configuration of the magnetoresistive effect element and the like in each current detection device unit is the same as that of the current detection device unit 6 shown in the first embodiment, and is not described in order to avoid duplication.
Each sensor circuit unit supplies the voltage of the bridge circuit 16 to the connection areas 14a and 14b of the respective current detection device units and outputs the output voltage of the bridge circuit 16 with appropriate amplification. In order to measure a magnetic field, the configuration of each sensor circuit unit such as an amplification factor may be different.
In the present embodiment, an example is shown in which each current detection device unit is installed below the space units 10 and 10a. However, the current detection device units may be installed inside the space units 10 and 10a other than the center and the center. Alternatively, the number is not limited to two and more may be provided.

次に、実施の形態３における電流センサ１の動作について、図１３により説明する。
一次導体３に被測定電流を印加すると、例えば第１のＵ字部形成一次導体４ａには電流の方向に対して図１３の破線に示すように左回転の磁界が、また第２のＵ字部形成一次導体４ｂには電流の方向に対して図１３の破線に示すように右回転の磁界が、また第３のＵ字部形成一次導体４ｃには電流の方向に対して図１３の破線に示すように右回転の磁界が、印加される被測定電流の大きさに応じて発生する。図には簡単のために各１次導体あたり１本の磁束線によって発生磁界を示した。
その結果、電流検知デバイス部６を空間部１０の下面近傍に設置した場合、電流検知デバイス部６の右側に位置する磁気抵抗効果素子１２ｃ、１２ｄには、図１４（ａ）に示す磁界ベクトル１１が印加され、磁気抵抗効果素子１２ｃ、１２ｄの感磁方向（Ｘ方向）には分解ベクトル１１ａが加わることになる。それぞれの分解ベクトルの大きさは、１１ａ＜１１ｂの関係が成立するため、Ｘ方向とＺ方向で比較した場合、Ｚ方向の１１ｂが主たる磁界の方向となる。つまり、電流検知デバイス部６のＸＹ面における、図５に示した磁気抵抗効果素子１２ａ、１２ｂには、中心線９より紙面左側の向きに磁界が加わり、磁気抵抗効果素子１２ｃ、１２ｄには、中心線９より紙面右側の向きに磁界が加わる。
第２の電流検知デバイス部６ｃを空間部１０ａ内の下面近傍に設置した場合、電流検知デバイス部６ｃの右側に位置する磁気抵抗効果素子１２ｃ、１２ｄには、図１４（ｂ）に示す磁界ベクトル１１が印加され、磁気抵抗効果素子１２ｃ、１２ｄの感磁方向（Ｘ方向）には分解ベクトル１１ｃが加わることになる。それぞれの分解ベクトルの大きさは、１１ｃ＜１１ｄの関係が成立するため、Ｘ方向とＺ方向で比較した場合、Ｚ方向の１１ｄが主たる磁界の方向となる。ここで図１４（ａ）に示す磁界ベクトル１１と図１４（ｂ）に示す磁界ベクトル１１は方向、および大きさの異なるベクトルであり、図のようにそれぞれの感磁方向の分解ベクトルの大きさは、１１ｃ＜１１ａの関係が成立する。Next, the operation of the current sensor 1 in the third embodiment will be described with reference to FIG.
When a current to be measured is applied to the primary conductor 3, for example, the first U-shaped primary conductor 4a has a left-rotating magnetic field as shown by a broken line in FIG. The part-forming primary conductor 4b has a clockwise magnetic field as shown by a broken line in FIG. 13 with respect to the direction of current, and the third U-shaped primary conductor 4c has a broken line in FIG. 13 with respect to the direction of current. As shown in the figure, a clockwise magnetic field is generated according to the magnitude of the current to be measured. For the sake of simplicity, the generated magnetic field is shown by one magnetic flux line for each primary conductor.
As a result, when the current detection device section 6 is installed in the vicinity of the lower surface of the space section 10, the magnetoresistive effect elements 12c and 12d positioned on the right side of the current detection device section 6 have a magnetic field vector 11 shown in FIG. Is applied to the magnetoresistive effect elements 12c and 12d in the magnetosensitive direction (X direction). Since the relationship of 11a <11b holds for the magnitudes of the respective decomposition vectors, when compared in the X direction and the Z direction, 11b in the Z direction is the main magnetic field direction. That is, a magnetic field is applied to the magnetoresistive effect elements 12a and 12b shown in FIG. 5 on the XY plane of the current detection device unit 6 in the direction of the left side of the drawing with respect to the center line 9, and the magnetoresistive effect elements 12c and 12d have A magnetic field is applied in the direction of the right side of the drawing from the center line 9.
When the second current detection device portion 6c is installed near the lower surface in the space portion 10a, the magnetoresistive effect elements 12c and 12d positioned on the right side of the current detection device portion 6c include magnetic field vectors shown in FIG. 11 is applied, and the decomposition vector 11c is added in the magnetosensitive direction (X direction) of the magnetoresistive effect elements 12c and 12d. Since the relationship of 11c <11d is established for the magnitudes of the respective decomposition vectors, 11d in the Z direction is the main magnetic field direction when compared in the X direction and the Z direction. Here, the magnetic field vector 11 shown in FIG. 14 (a) and the magnetic field vector 11 shown in FIG. 14 (b) are vectors having different directions and magnitudes, and the magnitudes of the decomposition vectors in the respective magnetic sensitive directions as shown in the figure. Holds the relationship 11c <11a.

このように、図１３に示す電流検知デバイス部６ならびに第２電流検知デバイス部６ｃの位置では、一次導体に近い位置であるにもかかわらず、それぞれの磁気抵抗効果素子１２の感磁方向には、主たる方向と異なる方向の低められた磁界が印加されることになる。そのため、被測定電流が大電流であっても磁気抵抗効果素子１２に印加される磁界が抑制され、出力の飽和などを気にすることなく、かつ電流センサとしての外形寸法を大型化することなく、大電流の計測が容易に行える。かつ、電流検知デバイス部６と第２電流検知デバイス部６ｃの位置で比較すると、Ｕ字形状の幅が広い、言い換えるとＵ字部形成一次導体の間隔が広い第２の電流検知デバイス部６ｃの位置で、より低められた磁界が印加されることになる。
つまり、第２の電流検知デバイス部６ｃの位置では、被測定電流が大電流であっても磁気抵抗効果素子１２に印加される磁界がさらに抑制され、出力の飽和などを気にすることなく、かつ電流センサとしての外形寸法をＺ軸方向に拡大することなく、大電流の計測が容易に行え、電流検知デバイス部６の位置では、被測定電流がやや小容量の電流になっても磁気抵抗効果素子１２に印加される磁界の抑制度は小さく、出力の低下によるＳ／Ｎの悪化などを気にすることなく、やや小容量の電流の計測が容易に行える。
例えば、各電流検知デバイス部６、６ｃのハーフブリッジ部分（例えば１７ｂ）に被測定電流値に対して付与される磁界は、図１５のように示され、やや小容量の電流の計測時は電流検知デバイス部６、大電流の測定時は電流検知デバイス部６ｃを利用するように構成すれば、各センサ回路部の増幅率等の若干の調整で、同じ特性の電流検知デバイス部を用いて、図１６に示すように測定レンジの拡大した精度の良い電流センサを構築することが可能となる。As described above, in the positions of the current detection device unit 6 and the second current detection device unit 6c shown in FIG. A lowered magnetic field in a direction different from the main direction is applied. Therefore, even if the current to be measured is a large current, the magnetic field applied to the magnetoresistive effect element 12 is suppressed, without worrying about output saturation, etc., and without increasing the external dimensions of the current sensor. , Large current can be easily measured. In addition, when compared at the position of the current detection device unit 6 and the second current detection device unit 6c, the U-shaped width is wide, in other words, the second current detection device unit 6c has a wide interval between the U-shaped primary conductors. In position, a lower magnetic field will be applied.
That is, at the position of the second current detection device unit 6c, even if the current to be measured is a large current, the magnetic field applied to the magnetoresistive effect element 12 is further suppressed without worrying about output saturation, In addition, it is possible to easily measure a large current without enlarging the outer dimensions of the current sensor in the Z-axis direction, and at the position of the current detection device unit 6, even if the current to be measured becomes a slightly small current, the magnetoresistance The degree of suppression of the magnetic field applied to the effect element 12 is small, and it is possible to easily measure a small capacity current without worrying about the deterioration of S / N due to a decrease in output.
For example, the magnetic field applied to the current value to be measured for the half-bridge portion (for example, 17b) of each of the current detection device units 6 and 6c is shown in FIG. 15, and the current is measured when measuring a slightly small current. If the detection device unit 6 is configured to use the current detection device unit 6c at the time of measuring a large current, the current detection device unit having the same characteristics can be used by slightly adjusting the amplification factor of each sensor circuit unit. As shown in FIG. 16, it is possible to construct an accurate current sensor with an expanded measurement range.

なお、実施の形態１と同様に、磁気抵抗効果素子１２ａ、１２ｄでは、共に磁界の増加に応じて抵抗値が増加すると共に、磁界の減少に応じて抵抗値が減少する磁気抵抗効果特性を有するように、また、磁気抵抗効果素子１２ｂ、１２ｃでは、逆に磁界の増加に応じて抵抗値が減少すると共に、磁界の減少に応じて抵抗値が増加する磁気抵抗効果特性を有するように構成されているため、一次導体３に流れる電流の増加に応じて磁気抵抗効果素子１２ａ、１２ｄの抵抗値が増加すると共に、磁気抵抗効果素子１２ｂ、１２ｃの抵抗値が減少し、一次導体３に流れる電流の減少に応じて磁気抵抗効果素子１２ａ、１２ｄの抵抗値が減少すると共に、磁気抵抗効果素子１２ｂ、１２ｃの抵抗値が増加する。このように、一次導体３に印加される被測定電流の大きさに応じてブリッジ回路１６の平衡が崩れ、これが各電流検知デバイス部６、６ｃのブリッジ回路１６の出力となる。本実施の形態３では２つのＵ字形状部を２つ有する構成としたが、これに限るものではなく、さらに複数のＵ字形状部を有する構成としてもよい。 As in the first embodiment, the magnetoresistive effect elements 12a and 12d both have a magnetoresistive effect characteristic in which the resistance value increases as the magnetic field increases and the resistance value decreases as the magnetic field decreases. Similarly, the magnetoresistive effect elements 12b and 12c are configured to have a magnetoresistive effect characteristic in which the resistance value decreases as the magnetic field increases and the resistance value increases as the magnetic field decreases. Therefore, as the current flowing through the primary conductor 3 increases, the resistance values of the magnetoresistive elements 12a and 12d increase, and the resistance values of the magnetoresistive elements 12b and 12c decrease, so that the current flowing through the primary conductor 3 As the resistance decreases, the resistance values of the magnetoresistive effect elements 12a and 12d decrease and the resistance values of the magnetoresistive effect elements 12b and 12c increase. Thus, the balance of the bridge circuit 16 is lost in accordance with the magnitude of the current to be measured applied to the primary conductor 3, and this becomes the output of the bridge circuit 16 of each of the current detection device sections 6 and 6c. In the third embodiment, the configuration has two U-shaped portions. However, the configuration is not limited to this, and a configuration having a plurality of U-shaped portions may be used.

以上のように、この実施の形態３によれば、設置基板上に４つの磁気抵抗効果素子で、設置基板の中心線に対して分けられた一方の領域に第１のハーフブリッジ回路が配置されると共に、他方の領域に第２のハーフブリッジ回路が配置され、それぞれのハーフブリッジ回路に逆方向の磁界が印加される構造のため、一様な外部磁界を除去することができる。 As described above, according to the third embodiment, the first half-bridge circuit is arranged in one region divided with respect to the center line of the installation board by four magnetoresistive elements on the installation board. In addition, since the second half bridge circuit is arranged in the other region and a magnetic field in the opposite direction is applied to each half bridge circuit, a uniform external magnetic field can be removed.

また、磁気抵抗効果素子の感磁方向への印加磁界を抑制する構成としたため、大電流の測定が容易に可能となり、さらに各電流検知デバイス部を空間部内に設置したため、一次導体を含めた電流センサの構造が小型となる効果がある。
また、一次導体の空間部１０、１０ａ内に異なる磁束密度が生じる構造のため、同じ特性の電流検知デバイス部を複数個設置して、小型で、かつ測定レンジを精度良く拡大できる効果がある。さらにまた、同じ特性の電流検知デバイス部が利用できるため、複数の異なる特性の電流検知デバイス部を用意する必要がなく、低コスト化となる効果がある。In addition, since the magnetic field applied in the magnetosensitive direction of the magnetoresistive effect element is suppressed, it is possible to easily measure a large current, and each current detection device is installed in the space, so that the current including the primary conductor is included. This has the effect of reducing the size of the sensor structure.
In addition, the structure in which different magnetic flux densities are generated in the space portions 10 and 10a of the primary conductor has an effect that a plurality of current detection device portions having the same characteristics can be installed to reduce the size and the measurement range with high accuracy. Furthermore, since the current detection device portions having the same characteristics can be used, it is not necessary to prepare a plurality of current detection device portions having different characteristics, and the cost can be reduced.

また、１枚のセンサ基板に複数の電流検知デバイス部を設置できる構成のため、センサ基板が１枚となるだけでなく、電流検知デバイス部の位置決めも容易となり、低コスト化となる効果がある。 In addition, since a plurality of current detection device units can be installed on a single sensor substrate, not only the sensor substrate is one, but also the current detection device unit can be easily positioned, resulting in cost reduction. .

実施の形態４．
図１７は、この発明の実施の形態４による電流検出装置２０の平面図を示すもので、図１８は図１７のＢＢ断面（ＹＺ面）を示す断面図である。本実施の形態４では、三相交流電流において、それぞれの相電流を３つの電流センサを用いて検出する電流検出装置２０を示したものである。
実施の形態４は、実施の形態１に示した電流センサを複数個用いた構成であり、その他の構成で重複する部分は省略する。Embodiment 4 FIG.
FIG. 17 shows a plan view of a current detection device 20 according to Embodiment 4 of the present invention, and FIG. 18 is a cross-sectional view showing a BB cross section (YZ plane) of FIG. In the fourth embodiment, a current detection device 20 for detecting each phase current using three current sensors in a three-phase alternating current is shown.
The fourth embodiment is a configuration using a plurality of current sensors shown in the first embodiment, and the redundant portions in other configurations are omitted.

実施の形態４における電流検出装置２０の全体構成について説明する。
電流センサ１、１ａ、１ｂがそれぞれ構成される３本の一次導体３、３ａ、３ｂは、長手方向（Ｘ方向）が略平行となり、かつそれぞれのＵ字形状部５、５ａ、５ｂが同一平面上に並列配置される。各一次導体に被測定電流が印加されたとき、発生する主な磁界の方向は、図１９の矢印に示すようにＸＹ平面において、全てＸ方向またはＹ方向となる。ここで、センサ基板２、２ａ、２ｂ上に設置された磁気抵抗効果素子（図には省略）の感磁方向はＸ方向であり、磁界検出部となるＵ字形状部５、５ａ、５ｂのＵ字部形成一次導体にて挟まれた部分に一次導体から付与される磁界の方向は、検出部のＸ方向磁界２１または検出部のＹ方向磁界２２となり、感磁方向と直角方向であるＹ方向の磁界の影響は受けない。それ以外において発生する非検出部の磁界方向２３は、磁気抵抗効果素子の感磁方向と直角方向であるＹ方向となるため、磁気抵抗効果素子は磁界検出部以外で発生する磁界の影響も受けることはない。
なお、本実施の形態においては、実施の形態１に示した電流センサを用いた例を示したが、他の実施の形態に示した電流センサを用いてもよく、複数個、あるいは組み合わせて設置しても構わない。また三相に限らず、さらに複数相、複数の一次導体を設置してもよい。The overall configuration of the current detection device 20 in the fourth embodiment will be described.
The three primary conductors 3, 3 a, 3 b that constitute the current sensors 1, 1 a, 1 b are substantially parallel in the longitudinal direction (X direction), and the U-shaped portions 5, 5 a, 5 b are on the same plane. Arranged in parallel on top. When a current to be measured is applied to each primary conductor, the direction of the main magnetic field generated is all in the X direction or the Y direction on the XY plane as shown by the arrows in FIG. Here, the magneto-sensitive effect element (not shown in the figure) installed on the sensor substrates 2, 2a, 2b is in the X direction, and the U-shaped portions 5, 5a, 5b serving as the magnetic field detection units are arranged in the X direction. The direction of the magnetic field applied from the primary conductor to the portion sandwiched between the U-shaped primary conductors is the X-direction magnetic field 21 of the detection unit or the Y-direction magnetic field 22 of the detection unit, and Y is perpendicular to the magnetic sensing direction. Unaffected by the magnetic field in the direction. The magnetic field direction 23 of the non-detection part that occurs elsewhere is the Y direction that is perpendicular to the magnetic sensing direction of the magnetoresistive effect element, so that the magnetoresistive effect element is also affected by the magnetic field generated outside the magnetic field detection part. There is nothing.
In this embodiment, an example using the current sensor shown in Embodiment 1 is shown, but the current sensor shown in other embodiments may be used, and a plurality or a combination of the current sensors may be used. It doesn't matter. Further, not only three phases but also a plurality of phases and a plurality of primary conductors may be installed.

以上のようにこの実施の形態４によれば、磁界検出部となる磁気抵抗効果素子部に、一次導体から付与される感磁方向の磁界以外に発生する磁界の方向が、感磁方向から直角方向となる構成のため、それらの磁界の影響を受けることがなく測定精度を高める効果がある。 As described above, according to the fourth embodiment, the direction of the magnetic field generated in the magnetoresistive effect element unit serving as the magnetic field detection unit other than the magnetic field in the magnetosensitive direction applied from the primary conductor is perpendicular to the magnetosensitive direction. Due to the configuration in the direction, there is an effect of improving measurement accuracy without being affected by the magnetic field.

この発明の実施形態１による電流センサの斜視図である。It is a perspective view of the current sensor by Embodiment 1 of this invention. この発明の実施形態１による電流センサの平面図である。It is a top view of the current sensor by Embodiment 1 of this invention. この発明の実施形態１による電流センサの断面図である。It is sectional drawing of the current sensor by Embodiment 1 of this invention. この発明の実施形態１による電流センサの電流検知デバイス部近傍の磁界ベクトルと分解ベクトルを示す図である。It is a figure which shows the magnetic field vector and decomposition | disassembly vector of the current detection device part vicinity of the current sensor by Embodiment 1 of this invention. この発明の実施形態１による電流センサの電流検知デバイス部を示す平面図である。It is a top view which shows the current detection device part of the current sensor by Embodiment 1 of this invention. この発明の実施形態１による電流センサの電流検知デバイス部を示す構成概略図である。It is a structure schematic diagram which shows the current detection device part of the current sensor by Embodiment 1 of this invention. この発明の実施形態１による補償導電線を配置した構成図である。It is a block diagram which has arrange | positioned the compensation electrically conductive line by Embodiment 1 of this invention. この発明の実施形態２による電流センサの断面図である。It is sectional drawing of the current sensor by Embodiment 2 of this invention. この発明の実施形態２による電流センサの電流検知デバイス部近傍の磁界ベクトルと分解ベクトルを示す図である。It is a figure which shows the magnetic field vector and decomposition | disassembly vector of the current detection device part vicinity of the current sensor by Embodiment 2 of this invention. この発明の実施形態２による電流センサの電流検知デバイス部の一部における被測定電流値−磁界関係図である。It is a measured current value-magnetic field relationship figure in a part of current detection device part of the current sensor by Embodiment 2 of this invention. この発明の実施形態２による電流センサの被測定電流値−センサ出力関係図である。It is a measured current value-sensor output relationship figure of the current sensor by Embodiment 2 of this invention. この発明の実施形態３による電流センサの平面図である。It is a top view of the current sensor by Embodiment 3 of this invention. この発明の実施形態３による電流センサの断面図である。It is sectional drawing of the current sensor by Embodiment 3 of this invention. この発明の実施形態３による電流センサの電流検知デバイス部近傍の磁界ベクトルと分解ベクトルを示す図である。It is a figure which shows the magnetic field vector and decomposition | disassembly vector of the current detection device part vicinity of the current sensor by Embodiment 3 of this invention. この発明の実施形態３による電流センサの電流検知デバイス部の一部における被測定電流値−磁界関係図である。It is a measured current value-magnetic field relationship figure in a part of current detection device part of the current sensor by Embodiment 3 of this invention. この発明の実施形態３による電流センサの被測定電流値−センサ出力関係図である。It is a measured current value-sensor output relationship figure of the current sensor by Embodiment 3 of this invention. この発明の実施形態４による電流検出装置の平面図である。It is a top view of the electric current detection apparatus by Embodiment 4 of this invention. この発明の実施形態４による電流検出装置の断面図である。It is sectional drawing of the electric current detection apparatus by Embodiment 4 of this invention. この発明の実施形態４による電流検出装置の一次導体近傍に発生する磁界の方向を示す図である。It is a figure which shows the direction of the magnetic field which generate | occur | produces near the primary conductor of the electric current detection apparatus by Embodiment 4 of this invention.

符号の説明Explanation of symbols

１電流センサ、２センサ基板、３一次導体、４Ｕ字部形成一次導体、５Ｕ字形状部、６電流検知デバイス部、７センサ回路部、８外部端子、９中心線、１０空間部、１１磁界ベクトル、１２磁気抵抗効果素子、１３接続電流線、１４接続エリア、１５設置基板、１６ブリッジ回路、１７ハーフブリッジ回路、１８補償導電線、１９オペアンプ、２０電流検出装置、２１検出部のＸ方向磁界、２２検出部のＹ方向磁界、２３非検出部の磁界方向DESCRIPTION OF SYMBOLS 1 Current sensor, 2 Sensor board | substrate, 3 Primary conductor, 4 U-shaped formation primary conductor, 5 U-shaped part, 6 Current detection device part, 7 Sensor circuit part, 8 External terminal, 9 Center line, 10 Space part, 11 Magnetic field vector, 12 magnetoresistive effect element, 13 connection current line, 14 connection area, 15 installation board, 16 bridge circuit, 17 half bridge circuit, 18 compensation conductive line, 19 operational amplifier, 20 current detection device, 21 X direction of detection unit Magnetic field, 22 Y-direction magnetic field of the detector, 23 Non-detector magnetic field direction

Claims

設置基板上に配置され、互いに逆方向の磁界の増加に応じて抵抗値が共に増加する磁気抵抗効果特性を有する第１および第４の磁気抵抗効果素子と、上記設置基板上に配置され、互いに逆方向の上記磁界の増加に応じて抵抗値が共に減少する磁気抵抗効果特性を有する第２および第３の磁気抵抗効果素子と、上記設置基板上に配置され、上記第１から第４の磁気抵抗効果素子を接続することにより、上記第１および第２の磁気抵抗効果素子による第１のハーフブリッジ回路、および上記第３および第４の磁気抵抗効果素子による第２のハーフブリッジ回路からなるブリッジ回路を構成する接続電流線とを備え、上記設置基板の中心線に対して分けられた一方の領域に上記第１のハーフブリッジ回路が配置されると共に、他方の領域に上記第２のハーフブリッジ回路が配置された電流検知デバイス部と、少なくとも１つのＵ字型形状を有する一次導体を備え、Ｕ字型形状を形成した上記一次導体に囲まれた空間内の少なくとも一箇所に、上記設置基板の中心線とＵ字型形状の対称軸が略一致するように上記電流検知デバイス部が配置されたことを特徴とする電流センサ。First and fourth magnetoresistive elements arranged on the installation board and having magnetoresistive effect characteristics in which the resistance value increases together with an increase in the magnetic field in the opposite direction, and arranged on the installation board, Second and third magnetoresistive elements having magnetoresistive effect characteristics that both decrease in resistance value as the magnetic field increases in the reverse direction, and disposed on the installation substrate, the first to fourth magnetic elements A bridge comprising a first half-bridge circuit composed of the first and second magnetoresistive elements and a second half-bridge circuit composed of the third and fourth magnetoresistive elements by connecting resistive elements. A connection current line constituting a circuit, and the first half bridge circuit is arranged in one area separated from the center line of the installation board, and the second area is arranged in the other area. A current sensing device unit half-bridge circuit is arranged, comprising a primary conductor having at least one U-shaped configuration, the at least one location in a space surrounded by the primary conductor to form a U-shaped configuration, the A current sensor, wherein the current detection device unit is arranged so that a center line of an installation board and a U-shaped symmetry axis substantially coincide with each other.

上記一次導体のＵ字型形状を形成する部分において、Ｕ字型形状の対称軸に直角方向の断面で、対称軸に相対する一次導体断面形状が同一形状であることを特徴とする請求項１に記載の電流センサ。2. The section of the primary conductor forming the U-shape is a cross section perpendicular to the symmetry axis of the U-shape, and the cross-sectional shape of the primary conductor facing the symmetry axis is the same shape. The current sensor described in 1.

少なくとも１つのＵ字型形状を有する上記一次導体において、長手方向に垂直な断面が長方形であることを特徴とする請求項１に記載の電流センサ。 The current sensor according to claim 1, wherein the primary conductor having at least one U-shape has a rectangular cross section perpendicular to the longitudinal direction.

上記電流検知デバイス部はセンサ回路部とともにセンサ基板に設置され、上記センサ基板はＵ字型形状を形成した上記一次導体に囲まれた空間内の少なくとも一箇所に、上記設置基板の中心線とＵ字型形状の対称軸が略一致するように配置されたことを特徴とする請求項２または３に記載の電流センサ。The current detection device unit is installed on the sensor substrate together with the sensor circuit unit, and the sensor substrate is disposed at least in one space in the space surrounded by the U-shaped primary conductor and the center line of the installation substrate and U The current sensor according to claim 2 or 3, wherein the shape-shaped symmetry axes are arranged so as to substantially coincide with each other.

請求項１から４いずれか記載の電流センサを、電流検出する相毎に配置して多相回路の電A current sensor according to any one of claims 1 to 4 is arranged for each phase for current detection, and the current of a multiphase circuit is set. 流を検出する電流検出装置であって、検出電流をそれぞれに印加する少なくとも１つのＵA current detection device for detecting a current, wherein at least one U for applying a detection current to each 字型形状を有した複数の一次導体を、一次導体の長手方向が略平行となるとともに各Ｕ字A plurality of primary conductors having a letter shape are formed so that the longitudinal direction of the primary conductors is substantially parallel and each U-shaped 型形状が同一平面にあるように並列配置したことを特徴とする電流検出装置。A current detection device, wherein the mold shapes are arranged in parallel so that they are on the same plane.