Patent ID: 9618541
Date: 2017-04-11
CPC Classifications: G01R

Claim:
1. An apparatus for sensing D.C. currents comprising: a dual core toroid including a first core defining a first circumference, a first central axis and a first central plane perpendicular to the first central axis, the first core being at least partially wound with a first insulated wire, a second core defining a second circumference, a second central axis and a second central plane perpendicular to the second central axis, wherein the first core and the second core are aligned such that the first central axis and the second central axis are substantially coaxial, the first central plane and the second central plane are substantially parallel and the first circumference and the second circumference define a combined circumference, the second core being at least partially wound with a second insulated wire, and a third insulated wire wound at least partially around the combined circumference of the first core and the second core, wherein the first insulated wire is wound around the first core in a first direction and the second insulated wire is wound around the second core in a second direction and is connected in series with the first insulated wire such that magnetic fluxes in the first core and the second core flow in opposite directions; a coil motor driver developing rectangular pulses coupled to the series connection of the first insulated wire and the second insulated wire; a signal amplifier having an input coupled to the third insulated wire and operative to develop an analog flux profile signal; an analog-to-digital (A/D) converter coupled to an output of the signal amplifier and operative to develop a digital flux profile signal; and a digital processor coupled to the A/D converter and to a non-transitory memory including code segments executable by the digital processor to calculate a sense current flow from variations between a quiescent digital flux profile and a distorted digital flux profile.