Detection of SF6 Decomposition Components Under Partial Discharge by Photoacoustic Spectrometry and its Temperature Characteristic

Photoacoustic (PA) spectrum is a promising method in SF6 decomposition product detection. To develop an on-line monitoring device, a gas detection system based on PA effect was introduced. Three kinds of gases, SO2, CO2, and CF4, were chosen to test the device performance. Some experiments were conducted to get the relationship of PA signal and gas concentration. The minimum detection limit of each gas was also measured. After that, the influence of temperature on PA detection was studied under 30 degrees C-50 degrees C. It is found that the PA signals of SO2 (1360 cm(-1)), CO2 (2347 cm(-1)), and CF4 (1285 cm(-1)) all have negative temperature characteristics within that temperature range. Then, a temperature linear correction model was proposed. The maximum error between correction result and standard PA signal under reference temperature was <4%. The temperature correction method lays a foundation for manufacturing SF6 decomposition components on-line monitoring device.