Fiber-Optic Current Sensor Head Based on the Giant Magnetostrictive Materials

Abstract

A current sensing method based on giant magnetostrictive material (GMM) and fiber Bragg grating (FBG) was proposed, which not only combines the advantages of FBG such as wavelength encoding, compatibility with fiber and distributed measurement system realization, but also the advantages of GMM as large flexible coefficient, high electromechanical coupling coefficient and short response time. The minimal residual method was put forward to effectively identify the Jiles-Atherton model parameters of ferro-magnetic material. The parameters of the giant magnetostrictive ( Terfenol-D bar ) and the Jiles-Atherton model was established and optimized by using the Mathematica software. Then the optical fiber current test system with ferromagnetic loop was set up to investigate the current sensing properties of the sensor. The relationship between current excitation and GMM-FBG reflected wavelength was obtained, which provides basic support for further current sensing experiment research.