A fiber optic Sagnac multi-stress sensor system

Fiber Bragg grating (FBG) sensors are employed in a fiber-optic Sagnac interferometer sensor to measure multi-stress information of electric power systems. By using the hybrid sensor configuration, it was possible to measure the temperature and the vibration signal in an insulating transformer oil bath at the same time. A novel fiber-optic Sagnac interferometer design and a signal processing technique were used to separate the FBG sensor signals from the interference signal. The preliminary experimental results are presented to show the feasibility of the sensor system.