A review of optical gas sensing technology for dissolved gas analysis in transformer oil

Frontiers in Physics, Год журнала: 2025, Номер 13

Опубликована: Фев. 5, 2025

Dissolved gas analysis (DGA) of transformer oil can deeply understand the operation status oil-immersed transformers, and detect early failures as possible, thus achieving purpose preventing further damage to transformer. It is a highly reliable method for identifying early-stage faults in transformers. This paper reviews commonly used sensing technologies analyzing dissolved gases oil, including Raman spectroscopy (RS), fourier transform infrared (FTIR), tunable diode laser absorption (TDLAS) photoacoustic (PAS). The progress research on these four reviewed, with detailed their respective principles characteristics. work provides guidance selection appropriate online preliminary technology, which essential assessment operating conditions ensure stable power systems.

Язык: Английский

Ppb-Level Photoacoustic Detection of Chloroform Using Four-Microphone Array

Analytical Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Янв. 15, 2025

The photoacoustic spectroscopy (PAS) system commonly enhances the efficiency of optical-acoustic-electrical energy conversion by increasing laser power, optimizing resonance characteristics cell (PAC), and improving sensitivity acoustic sensors. However, conventional systems using a single-microphone or dual-microphone differential setup for point sampling signal fail to account its spatial distribution, leading loss gain. Drawing on microphone array theory derived from sonar technology, this study, first time, presents PAS sensing based four-microphone array, which is applied detect chloroform gas. microphones are positioned at 90° intervals around PAC chamber wall, enhancing rate signals. A digital phase-locked algorithm demodulates combined signals four into concentration data. Experimental results show that, compared system, increases factor 4, doubles signal-to-noise ratio, achieves minimum detection limit 69 ppb, demonstrating significant improvement in capturing distribution PA

Язык: Английский

光声光谱技术及其生物医学检测应用（特邀）

Chinese Journal of Lasers, Год журнала: 2025, Номер 52(9), С. 0907201 - 0907201

Опубликована: Янв. 1, 2025