Study of Winding Optical Fiber in Fiber-optical Current Transducer

Winding optical fiber system in fiber-optical current transducer is proposed in order to research the fiber-optical current transducer based on magnetochiral effect. In the system, the sensing fiber is wound on the straight wire, and the laser is coupled into the sensing fiber after through the polarizer. When the current, whose value is determined by Faraday Effect, is loaded in the wire, the output optical power is measured by power meter to achieve the study on the measurement of current in high voltage transmission line based on magnetochiral effect. In the experiment, by comparing the depolarization to linearly polarized light by single-mode fiber and multimode fiber, single-mode fiber is more suitable for sensing material in this study; At the same time, by changing the radius of single mode winding optical fiber, the smaller the radius of winding optical fiber, after linearly polarized light through optical fibers, the more serious the depolarization, that is the birefringence effect has greater impact on the measurement accuracy; But being affected by the wire diameter and the surrounding magnetic field strength, as the fiber wound radius increases, the birefringence effect of the system decreases and then increases, showing the parabola opening upwards. The system is verified experimentally the different wound radius of fiber impact on testing of the system, and is of theoretical significance to research optical current transformer based on magnetochiral effect and practical application. It is verified by testing that when radius of 5m and 150m of single mode fiber are at 6 cm, 9.5 cm respectively, the Faraday Effect is the most obvious and has the highest precision.