The differential magnetic field sensing is proposed to detect the position of the electrode tip for the smelting of
the submerged arc furnace (SAF). The magnetic radiation model is established by the magnetic differences
between the electrode zone and electric arc zone in the industrial field of SAF and the differential magnetic
field sensing system is developed. The experiments are carried out under the environment of industrial field.
When the relative distance between the two probes is appropriately set, the field test curve can accurately
reflect the position of the electrode tip. Theoretical analysis and experimental results show that the difference of
the front end of the system can detect the position of the electrode tip and effectively avoid saturating the system.
Compared with the detection of magnetic field array sensing, the differential magnetic field detection
scheme is more effective for the position information of the electrode tip and has better practical value for
industrial measurement.