| 摘要 |
<p>PURPOSE:To detect an electric current under test with high accuracy even when an external conductor in which a large electric current flows exists in its neighborhood by a method wherein a connecting conductor which connects ends of the same polarity of shield windings is formed as a ring-shaped body with which the outer circumference of an iron core is covered and whose width is prescribed. CONSTITUTION:A first connecting plate 7 is formed to be ring-shaped; it is installed at the outside of shield windings 4a to 4d in such a way that they are covered. A ring-shaped body 8 which is a second connecting plate and which is provided with both sidewalls is installed at the outside of the first connecting plate 7 so as to be concentric with the first connecting plate 7. Thereby, a leakage inductance is small and an induced current flows easily. Since the outer circumference of an iron core 2 is covered with the connecting conductors 7, 8, a magnetic flux by an electric current flowing in an external conductor 6 creeps into the iron core through the connecting conductors 7, 8. However, the connecting conductors 7, 8 can make the induced current sufficient to offset the flux density flow easily. Consequently, even when the external conductor in which a large electric current flows exists in its neighborhood, an electric current under test can be detected with high accuracy.</p> |
