Isotopic Monitoring: A Novel Diagnostic and Life-Prediction Tool for Paper–Oil Insulation in Transformers

Isotopic monitoring adds a new dimension to transformer diagnostics by providing information that is not accessible through conventional chemical markers. In this work, we investigate the use of carbon isotopes and CO₂ isotopologue patterns as indicators of paper degradation in oilimmersed transformers and as inputs to predictive models for the degree of polymerisation (DP) of cellulosic insulation.