Abstract

An electric current monitor utilizing the Faraday effect in an optical fiber, for application to power facilities, has been anticipated because of its inherent features such as small in size, immunity to electromagnetic noise, etc. However, to realize stable characteristics of that, it is indispensable to prevent influence of birefringent effect on light passing the sensing fiber due to photo-elastic effect induced by perturbation from environment. A special single mode fiber manufactured from flint glass with very small photo-elastic constant was developed to solve the problem. Using the fiber, a current monitor was constructed and tested by the authors in cooperation with Hoya corporation.

© 1995 IEEE