| 摘要 |
<p>PURPOSE: To enhance the accuracy of measurement and high frequency characteristics by improving a magnetic circuit. CONSTITUTION: A main conductor 3 penetrates the inner cavity of a magnetic circuit 1 having an air gap 2 arranged with a magnetic detection element, i.e., a Hall element 5. A measuring coil 4 is disposed around magnetic circuit parts 7, 8 having the air gap 2. A yoke 6 serving as a magnetic shunt of the air gap 2 is arranged on a nonmagnetic coil case 9. The yoke 6 has length substantially equal to that of the coil 4. Flux generated from the main conductor 3 is canceled by a current flowing through the measuring coil 4 thus nullifying the flux in the air gap 2. Current flowing through the main conductor 3 can be detected from the current flowing through the measuring coil 4 at that time. Since the yoke 6 is arranged, accuracy of measurement is enhanced and the current can be detected with high accuracy up to a high frequency exceeding 100kHz.</p> |
