Immersion photoacoustic spectrometer (iPAS) for arcing fault detection in power transformers.

We report on the development of the first immersion photoacoustic spectrometer (iPAS) for arcing fault detection in power transformers. The spectrometer consists of a detection system and an all-optical photoacoustic sensing head mounted inside a small permeable chamber where dissolved C2H2 diffuses while the transformer oil is kept out. Our all-optical iPAS sensor can be placed directly inside an oil bath and measure dissolved C2H2 with the sensitivity and linearity needed for in situ arcing fault detection. Moreover, its fast response time holds great promise for extra-early fault diagnosis.