High-sensitivity dynamic analysis of dissolved gas in oil based on differential photoacoustic cell

Multi-mechanism collaboration enhanced photoacoustic analyzer for trace H2S detection

“…When the excitation source is modulated, periodic thermal expansion of the gas produces photoacoustic signals [12] , [13] . The concentration of the target gas can be obtained by measuring the photoacoustic signals through acoustic sensors [14] , [15] , [16] . Benefiting from the background-free detection mechanism, PAS as indirect absorption spectroscopy technology has a wider dynamic range and more sensitive gas detection performance than traditional direct ASGAT.…”

Pt-Doped HfS2 Monolayer as a Novel Sensor and Scavenger for Dissolved Gases (H2, CO2, CH4, and C2H2) in Transformer Oil: A Density Functional Theory Study

“…Until now, it has been widely accepted that DGA, a technology for monitoring the production situation of the gas mentioned above, is one of the most reliable methods for assessing the health status of oil-filled power equipment . Gas sensors for testing periodically the constituent gases in transformer oil include chemical resistance type, infrared spectroscopy type, photoacoustic spectroscopy type, and chromatography type . Compared to other types of sensors, a resistivity-type sensor delivers the merits of high sensitivity, , low expense, , and easy integration, , which makes it most likely to be widely used in detecting dissolved gases in oil.…”

Multi-pass Differential Photoacoustic Sensor for Real-Time Measurement of SF6Decomposition Component H2S at the ppb Level

“…The two PA signals in the differential photoacoustic cell (DPAC) are processed differentially, doubling the amplitude of the perceived signal and effectively eliminating the flow noise. , In the field of dynamic monitoring, the DPAC improves the detection accuracy and real-time performance of the sensing device from the perspective of acoustic resonance enhancement. In 2017, Yin et al achieved an MDL of 109 ppb for H 2 S in the SF 6 background gas using a DPAC and a DFB laser with the central wavelength of 1582 nm .…”

“…The simulation analysis of the effect of temperature on the infrared absorption lines of H 2 S was carried out in the range of 1574.5 to 1574.65 nm. The gas pressure is constant at 0.1 MPa, and the absorption spectra at four temperature gradients of 25 ■ INTEGRATION OF THE H 2 S PA SENSOR Design and Optimization of the MDPC. According to the Beer−Lambert absorption law, the sensitivity of gas detection is proportional to the total absorption path length.…”