A magnetostrictive sensor interrogated by fiber gratings for DC-Current and temperature discrimination

A magnetostrictive sensor head with temperature compensation has been devel oped for measurement of static magnetic fields. The device consists on two different alloys with similar thermal expansion coefficient one of which ha s a giant magnetostriction, the expansion of both materials produced by hea t and magnetism is detected by two fiber gratings. One of the gratings meas ures the temperature of the sensor and the difference between the wavelengt hs reflected by the gratings is a measurement of the magnetically induced s train.