Model and Experimental Study on Optical Fiber CT Based on Terfenol-D

Area of Science:

• Materials Science
• Magnetism
• Thermodynamics

Background:

• Terfenol-D exhibits complex magneto-mechanical-thermo coupling behavior.
• Accurate modeling is crucial for advanced material applications.
• Fiber Bragg gratings offer precise strain sensing capabilities.

Purpose of the Study:

• To develop a nonlinear hysteresis model for Terfenol-D materials.
• To design and analyze a fiber current transformer based on Terfenol-D and fiber Bragg gratings.
• To investigate the influence of operational parameters on the current transformer's performance.

Main Methods:

• Utilized Wiss ferromagnetic theory, thermodynamics, and the Jiles-Atherton model for hysteresis modeling.
• Employed numerical calculations and experimental validation.
• Integrated fiber Bragg grating strain sensing with an unbalanced Mach-Zehnder interferometer for demodulation.

Main Results:

• The proposed model effectively captures the magnetostrictive characteristics of Terfenol-D under coupled stress, temperature, and magnetic fields.
• The designed fiber current transformer demonstrated functional principles.
• Analysis revealed the impact of prestressing force and bias current on transformer performance.

Conclusions:

• The developed nonlinear hysteresis model provides a robust framework for Terfenol-D material characterization.
• The Terfenol-D-based fiber current transformer shows promise for practical implementation.
• Understanding parameter influences is vital for optimizing current transformer design and application.