Design of distributed feedback fiber laser sensing system for power transformers vibration monitoring

Based on the advantages of Distributed Feedback fiber laser (DFB-FL), such as narrow line width, low noise and long coherence length, a vibration sensing system was designed and used to detect transformers vibration in this paper. The DFB-FL glued on the cantilever was used as the sensing element, the wavelength change of DFB laser was converted into the output intensity change of the interferometer by using unbalanced fiber Michelson interferometer. Cantilever was designed and vibration characteristics was simulated by COMOSOL software with different material. The vibration signal of the winding of the transformer was detected with vibration frequency centered at 100Hz,750Hz, 800Hz and 850Hz.