We estimated the influence of polarization crosstalk in a Sagnac-type optical current transformer (OCT) against sensor sensitivity, and confirmed that temperature dependence of Faraday effect is canceled out by controlling the extinction ratio of transmission fiber with temperature change. Based on the above evaluation, we developed a temperature compensation element (TCE) consisting of metal-coated PM fiber. Its extinction ratio varies with temperature because of the difference between the linear expansions of metal and fiber. The ratio error of OCT using this TCE in the temperature range from -40°C to 80°C was within 0.1%, and satisfied the required accuracy for IEC 60044-8 class 0.2S.

Date Published: 2 June 2014
PDF: 4 pages
Proc. SPIE 9157, 23rd International Conference on Optical Fibre Sensors, 91571Z (2 June 2014); doi: 10.1117/12.2058754

Published in SPIE Proceedings Vol. 9157:
23rd International Conference on Optical Fibre Sensors
José M. López-Higuera; Julian D. C. Jones; Manuel López-Amo; José Luis Santos, Editor(s)