Positiivisen ja negatiivisen viritysvirran vaikutuksesta helposti kyllästyvää magneettista ydintä käytetään saamaan magneettisydämen induktanssi muuttumaan viritysvirran suuruuden mukaan siten, että magneettisydämen magneettivuo muuttuu jatkuvasti.

The fluxgate-virta-anturi uses the non-linear relationship between the magnetic induction intensity and the magnetic field intensity of the high magnetic permeability core in the measured magnetic field under the saturation excitation of the alternating magnetic field to measure the weak magnetic field. This physical phenomenon seems to be a “gate” to the measured ambient magnetic field. Through this “gate”, the corresponding magnetic flux is modulated and an induced electromotive force is generated. This phenomenon is used to measure the magnetic field generated by the current, so as to indirectly achieve the purpose of measuring the current.