Birefrigence Optimization Algorithm of the Polarimetric CT System

We developed a fiber-optic current sensor system for the over-current protection relay. A spun fiber was employed to eliminate linear birefringence effect, and to compare the efficiency a twisted and a Flint glass fiber were also tested. From the experimental results, we obtained less than 2% of linear error with spun fiber output according to current increases. The SNR at 60 Hz is measured to be more than 55 dB. The spun fiber sensor coil showed the sensitivity of about 6 and 35 dB better than the Flint glass fiber and twisted fiber, respectively.