Lead wire DC current sensor with saturated detecting core

Abstract

A DC current sensor, comprising a detecting core consisting of an annular soft magnetic material having a hollow portion extending in a circumferential direction within the core; an excitation coil wound and disposed in a circumferential direction in the hollow portion; a detecting coil toroidally wound around the detecting core; a lead wire through which a DC current for non-contact detection flows, and extended through the center of the detecting core; an AC current supply for applying current to the excitation coil for periodically magnetically saturating the entire detecting core in both the circumferential and a direction perpendicular thereto, whereby the magnetic flux produced in the detecting core can be modulated according to the DC current flowing through the lead wire and being detected upon excitation of the excitation coil; and the detecting coil producing an electromotive force having a frequency twice the excitation current for detecting the DC current flowing through the lead wire.

Dependencies are inferred from the claim text.