New Photoacoustic Detection Method for Acetylene Dissolved in Transformer Oil

Acetylene always arises from the discharge faults of power transformers. A photoacoustic spectrometer was developed and it has been applied to the detection of acetylene using a properly designed photoacoustic cell on its first longitudinal mode. Experimental results show that the photoacoustic signal has a significant linear correlation with the gas content and the laser power under low gas content or low laser power. The minimum detection limit of acetylene is about 1.43 part-per-million by volume. Moreover, in this paper we also describe some basic theory of gas photo-acoustic spectroscopy.