| 摘要 |
<p>PURPOSE:To prevent detection of a noise magnetic field by winding coils in such a manner that a spiral coil and a one-turn coil have the same area in a Rogowski coil. CONSTITUTION:A spiral coil is formed of circular coil parts 5a, 5b... along the circumferential direction of a ring form, of extension parts 6... continuing to a circular coil 5 constituted by said coil parts in the direction toward the center of a ring, of small loop coils 7... each of which forms one turn in the shape of a loop intersecting the extension part 6 perpendicularly, and of extension parts 8... continuing to the coils 7 and joining to the starting ends of subsequent coils 5a, 5b..., etc. By this constitution, the spiral coil and a one-turn coil are to have the same area, and noise components in the direction of a measured current are canceled by the coil 5 and the coil 3 wound in the reverse directions and overlapping each other when a high current pulse and the like are measured, while noises caused by the local difference in the change with time of a magnetic field component are not detected. Thus, measurement with the excellent S/N ratio can be performed.</p> |
