Type of rotating disc magnetic field probe

Abstract

A type of rotating disk magnetic field probe () comprising: a non-magnetic rotating disk (),N first soft ferromagnetic sectors (), M second soft ferromagnetic sectors (), a reference signal generator, an X-axis magnetoresistive sensor (), a Y-axis magnetoresistive sensor (), and a Z-axis magnetoresistive sensor (). Both the first soft ferromagnetic sectors () and the second soft ferromagnetic sector () are located on the non-magnetic rotating disk (). In operation, the non-magnetic rotating disk () rotates about a Z-axis at a frequency f. An external magnetic field is modulated by the first soft ferromagnetic sector () into an X-axis magnetic field sensed component and a Y-axis magnetic field sensed component having a frequency of 4N×f, and is modulated by the second soft ferromagnetic field sectors into a Z-axis magnetic field sensed component having a frequency of M×f. The X-axis sensed magnetic field component, the Y-axis sensed magnetic field component, and the Z-axis sensed magnetic field component respectively are converted into output signals by means of the X-axis magnetoresistive sensor () the Y-axis magnetoresistive sensor () and the Z-axis magnetoresistive sensor (). The reference signal generator respectively outputs a first reference signal having a frequency of 4N×f and a second reference signal having a frequency of M×f. The first reference signal, the second reference signal, and the measurement signals are demodulated by an external processing circuit to output magnetic field values Hx, Hy and Hz.