Use of fiber optic sensor techniques for monitoring and diagnostics of large ac generators

Abstract

A method for monitoring the operating conditions of an electric generator for mechanical strain and temperature includes means of distributive fiber optic sensors based on both Rayleigh back scattering techniques and Brillouin frequency shift fiber optic sensor analysis as both Rayleigh and Brillouin scans and allow accurate strain and temperature determinations at all points along standard fiber optic cables of considerable length, which effectively yields thousands of sensors throughout the entire standard fiber optic cable. Raman distributive temperature sensing also has a limited application. Single mode and polarizing maintaining fibers can both be analyzed and read with any Rayleigh or Brillouin distributive fiber optic sensor laser system allowing great flexibility in sensor spatial resolution, total sensed length, resolution and other factors. A sealed fiber collection box located outside the electric generator permits enhanced reliability and reconfiguration into any number of desirable fiber layouts necessary for specific static and dynamic measurements.