Magnetostriction Offset of Fluxgate Sensors

Abstract

Magnetostriction is generally believed to cause excessive offset and noise in fluxgate sensors. We show that although the magnetostrictive core tapes are susceptible for offset instability, there is no simple direct mechanism for generation of 2 nd harmonic signal by magnetostriction. Offset and noise are caused by variation of local core properties and mechanical stresses together with magnetoelastic coupling.