Wide Range Orthogonal Fluxgate Sensor Fabricated With Cylinder-Shaped Ferrite Core

Abstract

In this study, we investigate the output properties of the orthogonal fluxgate sensor fabricated with a cylinder-shaped ferrite core, and examine whether it could show both high sensitivity and wide measurement range for the application of magnetic treatment facility for surface vessels and submarines. The excitation coil and pickup coil are 10 turns and 280 turns respectively. To gain the wide measurement range over 30 Oe, we design the shape of magnetic core through FEM analysis. It is found that a stable fundamental mode operation would be possible when an adequate DC bias is adding to alternating excitation current. There is a resonant peak in the operation frequency dependence of output voltage, which is caused by LC resonance of pickup coil and coaxial cable. The maximum sensitivity was ~2 V/Oe at 870 kHz, and the output increased almost linearly by external magnetic field to reach ~30 Oe.