REDUCING HYSTERESIS IN MAGNETOSTRICTIVE-PIEZOELECTRIC MAGNETIC SENSORS

In this paper, we present a method to avoid hysteresis in magnetostric tive-piezoelectric sensors. It is based on the application of an alter nating magnetic field of a frequency different than the piezoelectric exciting frequency that supplies enough energy to; overcome any domain wall pinning. The signal is filtered with a notch filter synchronized to the magnetic field frequency and thus it does not contribute to th e useful response of the sensor. The results show an appreciable decre ase in the magnetic hysteresis and also a small decrease in the sensib ility of the sensor.