Research on Fiber-enhanced Raman Spectroscopy Detection of Transformer Hydrocarbon Fault Gas.

Analysis of transformer hydrocarbon fault gas concentration can effectively evaluate its operating status. This paper proposes a new fiber-enhanced Raman spectroscopy with fluorescence noise filtering, which can solve the problems of aging, cross-interference and timesharing measurement of existing detection methods. The proposed collaborative fluorescence filtering method can increase the detection capability of the original detection method by 2.1 times, which ensures $\mu L/L$ level detection of transformer hydrocarbon fault gases; the response time of the system can reach 60 s, which enables the system to achieve dynamic detection of the transformer hydrocarbon fault gas; the system’s lower detection limit for transformer hydrocarbon fault gases can reach the $\mu L/L$ level $(CH_{4}$ is 1.0 $\mu L/L, C_{2}H_{2}$ is 2.2 $\mu L/L, C_{2}H_{4}$ is 1.8 $\mu L/L, C_{2}H\epsilon$ is 4.6 $\mu L/L,H_{2}$ is S.2 $\mu L/L, CO_{2}$ is 6.4 $\mu L/L$, CO is 13.6 $\mu L/L$ with the laser power of 200 mW, the exposure time of 60 s and pressure of 0.1 MPa); the system’s good detection accuracy of less than 3% for various transformer hydrocarbon fault gas $(CO_{2}$ is 2.3%, $C_{2}H_{2}$ is 1.0%, CO is 2.2%, $CH_{4}$ is 0.9%, $C_{2}H\epsilon$ is 1.7%, $H_{2}$ is 1.5%, $C_{2}H_{4}$ is 1.4%) is obtained. This research lays the foundation for the simultaneous, dynamic and accurate analysis of hydrocarbon fault gases in transformer.