Correlation of hydrogen generation with sparking discharges in a mineral insulating oil

Dissolved gas analysis (DGA) of transformer oil is one of the key methods of assessing transformer health [1]. Transformers operate under multiple stresses, e.g., thermal, electrical, and mechanical. The hydrocarbon molecules of transformer oils can be degraded into combustible and incombustible gases under high thermal and electrical stresses, particularly under fault conditions. Different generated gases correspond to specific fault types and levels, e.g., hydrogen is the primary indicator of corona partial discharge, and acetylene is the primary indicator of sparking discharge and high-energy breakdown [2], [3]. DGA technology is therefore widely used to reveal incipient transformer faults by measuring the concentration of fault gases in the transformer oil.