Hysteretic Interference of Magnetic Field of a Moving Linear Inductor

Abstract

Coordinate distributions U(x) were calculated for the electric voltage across a magnetic field sensor scanning a magnetic carrier with recordings of pulsed magnetic fields from a linear inductor moved discretely with a given pitch above the magnetic carrier surface. The magnetic carrier was acted upon with pulses of one direction and with oppositely directed pulses. The characteristics of the magnetic field sensors used in experimental studies were expressed as analytical arctangent functions. An arctangent initial curve and hysteresis branches of the dependence of electric voltage U(H) across the magnetic field sensor on magnetic field strength when the sensor scans a magnetic carrier are presented. These curves correspond to the distribution of remanent magnetization in the magnetic carrier in a pulsed magnetic field. The sensitivity of the magnetic field sensors used in the calculations was $${{\gamma }_{{{\text{max}}1}}} = $$ 1.0 mV cm/A, $${{\gamma }_{{{\text{max}}2}}} = $$ 0.26 mV cm/A, $${{\gamma }_{{{\text{max}}3}}} = $$ 2.8 mV cm/A. Sequences are established in which the remanent magnetization changes in the magnetic carrier exposed to unipolar and bipolar magnetic-field pulses. Hysteretic interference is represented as the interference of the distributions of the electric voltage across the sensor in a pulsed magnetic field U(x) along the coordinate x. The results of calculations of the magnitude of electric voltage U across the sensor are presented for layers of aluminum foil with a thickness on the order of 0.05 mm by hysteretic and anhysteretic methods. It is shown that the use of hysteretic interference can increase threefold or more the sensitivity of measuring instruments.