METHOD AND CIRCUIT FOR COMPENSATING BARKHAUSEN SIGNAL MEASUREMENTS IN MAGNETIC MATERIALS HAVING A VARIABLE GEOMETRY

摘要

In one exemplar embodiment, a feedback circuit in a Barkhausen signal measuring system is utilized to reduce variations in the measured Barkhausen signal due to the geometry of the magnetic body. The improvement utilizes a magnetic flux detector disposed in the area adjacent where the Barkhausen signal is measured for detecting the magnetic flux density of the test body. The signal generated by the detector is fed back to a gain control for controlling the gain of the power source providing the time-varying current to the Barkhausen signal measuring system, the gain control controlling the magnitude of the time-varying current in order to maintain the rate of change of the magnetic flux in the body in the area of the detector at a predetermined value.