CURRENT SENSOR

• Main Authors: UMEZU JUN, OKUYAMA TAKESHI, TOMITA YUJIRO, FUTAKUCHI NAOKI, AKIMOTO KATSUYA
• Format: Patent
• Language: English; Japanese
• Published: 17.01.2019
• Subjects: MEASURING; MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES; PHYSICS; TESTING

To provide a current sensor with which it is possible to reduce hysteresis and detect a current with high accuracy.SOLUTION: The current sensor comprises a busbar 2 in which a current to be measured flows, a first shield plate 41 and a second shield plate 42 arranged so as to sandwich the busbar 2 in the thickness direction of the busbar 2, and a magnetism detection element 3 for detecting the strength of a magnetic field generated by the current flowing in the busbar 2, the distances of the first shield plate 41 and second shield plate 42 from the busbar 2 being equal, the magnetism detection element 3 being arranged so that its magnetism sensing position is shifted to the first shield plate 41 side from the center position in the thickness direction of the busbar 2, the second shield plate 42 consisting of a single magnetic layer 42a or a laminate in which a plurality of magnetic layers are laminated via an insulator, the first shield plate 41 consisting of a laminate in which a plurality of magnetic layers 41a, 41c are laminated via an insulator 41b, with the number of layers of the laminate larger than the second shield plate 42.SELECTED DRAWING: Figure 1 【課題】ヒステリシスを低減し精度よく電流を検出可能な電流センサを提供する。【解決手段】測定対象となる電流が流れるバスバ２と、バスバ２をバスバ２の厚さ方向に挟み込むように配置されている第１シールド板４１及び第２シールド板４２と、バスバ２を流れる電流により発生する磁界の強度を検出する磁気検出素子３と、を備え、第１シールド板４１及び第２シールド板４２のバスバ２からの距離が等しく、磁気検出素子３は、その感磁位置がバスバ２の厚さ方向における中心位置よりも第１シールド板４１側にずれるように配置されており、第２シールド板４２は、単層の磁性体層４２ａ、あるいは絶縁体を介して複数の磁性体層を積層した積層体からなり、第１シールド板４１は、絶縁体４１ｂを介して複数の磁性体層４１ａ，４１ｃを積層した積層体からなり、かつ、当該積層体の層数が第２シールド板４２よりも多い。【選択図】図１