A novel model for the detector coil inductance of ring-core fluxgate sensors

• We develop a physical model for detector coil inductance of ring-core fluxgate.
• We develop two kinds of fluxgate sensors with one and two sections detector coil and perform the responding experiments.
• We study the influence of the sections distance and the winding area on the detector coil inductance.

In this paper, we develop a physical model to evaluate the detector coil inductances for ring-core fluxgate sensors. Using realistic magnetization parameters, we study the inductance variation with different excitation currents. We perform the corresponding experiments to measure the detector coil inductances, and find that the average deviation between the calculated and the measured results is less than 5.7%. We also investigate the influence of the distance between coil sections and the winding area on the detector coil inductances. The results reveal that the inductance model can be used to determine the geometry and the size of the sensor.