Design Fluxgate Magnetometer (Fiuxgate Sensor)

Fluxgate magnetometers have been used by robotic space probes to analyze, map and
monitor the magnetic fields of the earth and other planets. They are also used in
geological prospecting, aerospace navigation, underwater navigation, land navigation and
submarine detection.
The objective of this project is to build fluxgate sensor for measuring a magnetic field,
The flux gate sensor has two ferromagnetic core, a primary, electrically conducting coil
arranged around the core for periodical magnetization of the core into magnetic saturation
by an alternating electric current through the primary coil, and a secondary, electrically
conducting coil arranged around two ferromagnetic core.
The Methodology of the project has been carry out with precise decision in order to find a
way to reduce the size, power consumption and cost, hence the author use low saturation
flux density materials.
The design and testing of a fluxgate sensor, which is totally embedded in printed circuit
board, has been presented. The sensor is suitable for sensing currents in the printed circuit
board traces. The sensitivity has been measured at 150 m VI A for 50 kHz excitation. The
power dissipation has been measured at approximately 1.44 W for a sinusoidal excitation.
The power dissipation can almost certainly be reduced by using pulse excitation, or
perhaps by using a saturable inductor in the excitation circuit. It is also possible to
improve the sensitivity and reduce the power consumption by use of an improved
magnetic material. In particular a material with lower saturation flux density and higher
permeability should be possible.
Future work will focus on further characterization of the sensor in terms of bandwidth,
noise level, and minimum current detection level.