20150331015 | FLUX-GATE TYPE NON-CONTACT CURRENT MEASURING DEVICE - The present invention relates to a flux-gate type non-contact current measuring device for measuring a current to be measured by detecting an electromagnetic field around a conducting wire into which the current to be measured flows, wherein the present invention can detect a direct current component through a change of an oscillating signal by applying the oscillating signal for magnetizing two cores in mutually opposite polarities, wherein: an LC oscillation circuit is formed by using the inductance of a coil wound on one core, and the direct current component is detected by applying an LC-oscillating signal to a coil wound on the other core; an alternating current component is detected by using another core; compensated currents corresponding to the detected direct current and alternating current components are converged under a condition of offsetting a magnetic flux by the current to be measured so that the current to be measured can be measured by measuring the compensated currents in the converged state thereof; and the present invention can normally measure a current by automatically demagnetizing an LC oscillating core even in a circumstance that the LC oscillating core is saturated by the current to be measured. | 11-19-2015 |