Fiber bragg grating technology used in temperature online monitoring for GIS bus contact

The contact of Gas insulated switchgear (GIS) will become loose in its long-term operation, which directly leads to partial discharge and overheating. This paper described an online temperature monitoring technology based on fiber Bragg grating (FBG) for GIS bus contact. Temperature distribution of GIS bus was established by coupled method of electromagnetic and thermal field. To monitor the bus temperature accurately, a novel FBG sensor that combined plating and welding technology together was designed. Comparing with other FBG sensors, it was proved to have a high sensitivity up to 30 pm/°C and a pretty well linearity. Finally, wavelength interrogation system was utilized to realize wavelength and temperature modulation. The paper for the first time applied FBG sensors to GIS temperature monitoring and could detect fault in advance, which was quite beneficial to the operation of GIS and power transmission.