High-frequency oscillation parametric current sensor with feedback loop

This paper deals with a noncontact current sensor that operates from DC to high frequency. This sensor utilizes the phenomenon of parametric oscillation, whereby the parametric oscillation voltage is amplitude-modulated by the magnetic field of the measured current. The proposed sensor has been operated closed loop up to 3 kHz for measured current and as expected has better performance characteristics than the open loop version. In this paper, we describe the features of this novel current sensor and ways to extend the high-frequency limit. Experimental results are given to support the theoretical analysis