| 摘要 |
<p>PURPOSE:To provide a high-sensitivity direct current sensor which has a simple structure and an excellent detecting ability even against a DC earth leakage breaker, etc., especially, against very small current changes. CONSTITUTION:A direct current sensor is constituted by forming hollow sections 52 communicating with each other in the peripheral direction in an annular detecting core 51 composed of a soft magnetic material and arranging exciting coils 53 wound in the peripheral direction in the hollow section 52 and toroidally wound detecting coils 54 on the outer peripheral surface of the core 51. As a result, the core 51 can be constituted in a highly productive structure. In addition, since the coils 53 and 54 are effectively arranged, the influence of the coercive force the soft magnetic material constituting the core 51 essentially has, the influence of leakage magnetic fluxes from the coil 53, etc., can be remarkably reduced. Therefore, a direct current sensor which can detect even such a very small current as 5mA with extremely high sensitivity can be obtained.</p> |
