Design and implementation of highly sensitive SF6 gas sensor

Sulfur hexafluoride (SF6) leakage will reduce the insulation performance of high-voltage equipment and affect the safe and stable operation of the equipment. An SF6 gas sensor was designed, which combines atmospheric pressure photoionization (APPI) source with High-field asymmetric waveform ion mobility spectrometry (FAIMS) and uses acetone as a dopant to achieve high-sensitivity detection of SF6. The effects of dispersed voltage and gas flow rate on the detection of SF6 were studied, and the spectra of SF6 at different concentrations were obtained. The experimental results indicate that using acetone as a doping agent can achieve efficient ionization of SF6. The detection sensitivity of SF6 shows a trend of first increasing and then decreasing with the increase of gas flow rate. The concentration of SF6 has a linear relationship with the ion signal intensity, the linear coefficient is 0.979, and the detection limit of SF6 is 0.2 ppm. This study is expected to provide fast and highly sensitive sensor support for SF6 leakage in high-voltage equipment.