Abstract: In response to the demand for higher precision and higher resolution magnetic measurement technology, especially for the improvement of the performance index of weak magnetic measurement technology, based on the principle of magnetic induction electromagnetic, using integrated fluxgate chip, a sensor component structure which can be used in weak magnetic three-dimensional vector field is designed. The influence of coil current, temperature and environment circuit of generating device of weak magnetic field is studied. The three- dimensional distribution characteristics of the magnetic field coil are analyzed and calculated by Ansys simulation software, and the magnetic field intensity and direction of the random space test point are determined. The heat dissipation of coil current is analyzed by COMSOL physical field calculation software. The experimental results show that the test data is basically consistent with the simulation results, so the excitation current condition of the weak magnetic field generator is determined. The system accurately measures the distribution and change of magnetic field vector of geomagnetic field with different latitudes and longitudes. The magnetic vector integral of 20 000 space points for the vector of any closed curve are realized, the curl theorem of static magnetic field is verified experimentally. 

Key words: weak magnetic field vector, flux sensor assembly, geomagnetic field vector, curl theor