Experimental study on fiber Bragg grating electric current sensor

A new electric current sensor based on fiber Bragg grating tuned by giant magnetostrictive material rod is demonstrated in this paper. A fiber Bragg grating is firmly clung on a giant magnetostrictive rod that is put into the central part of a solenoid. The Bragg wavelength of the fiber grating will shift when the uniform magnetic field in the solenoid changes. The rod will have elastic lengthening along the direction of the magnetic field. The grating resonant wavelength of fiber grating will shift as consequence of the rod lengthening The relationship between the electric current and the wavelength shift is basically linear. The wavelength range of linear tuning is about 0.9nm. The tuning sensitivity is about 0.001nm/mA.