High sensitivity detection method for insulation status of eco-friendly gases GIS equipment based on photoacoustic spectroscopy technology

Aiming at the problems of gas pressure fluctuation and background noise in the insulation state detection of gas insulated switchgear (GIS) equipment, a high sensitivity detection method for the insulation state of eco-friendly gases GIS equipment based on photoacoustic spectroscopy technology was proposed. The method used photoacoustic spectroscopy technology to suppress background noise and accurately detect the components of eco-friendly gases. Combined with the maximum correlation minimum redundancy criterion, the insulation state characteristics were optimized to improve the detection pertinence. High sensitivity detection was achieved by building a model with support vector machine. The detection process included photoacoustic signal detection, noise suppression, component concentration determination, feature selection and classification. Experiment results on C₄/CO₂ gas mixtures demonstrated a fitting accuracy of 0.978 for C₄ compoment, and the dynamic response entropy index consistently remaining below 0.1, indicating that the proposed method has excellent detection sensitivity for monitoring the insulation state of eco-friendly gas GIS equipment, capable of accurately capturing the micro molecular movement changes. This provides a reliable basis for the early diagnosis of equipment insulation deterioration.