| 摘要 |
<p>PROBLEM TO BE SOLVED: To meet detection of a large current without increasing the number of winds of a coil and a current thereof and, moreover, to attain miniaturization. SOLUTION: When a current Im flows through a conductor 1, a magnetic fluxϕis generated in a ring core 2, a magnetic field is generated in a gap part 2a, a part thereof is impressed on a magnetoelectric element 3 and an electric signal Es corresponding to the strength of the magnetic field is outputted from the magnetoelectric element 3. A control part 9 supplies an exciting current Ic to an exciting winding 5 in accordance with this electric signal Es and a magnetic field generated in the exciting winding 5 so acts as to cancel the magnetic field impressed on the magnetoelectric element 3. Since the exciting current Ic is in proportion to the magnetic fluxϕ, the current Im flowing through the conductor 1 can be detected from the exciting current Ic.</p> |
