Abstract
The paper presents an improved model for early fault prediction of power transformers based on a comprehensive dissolved gas analysis (DGA) in transformer oil. The purpose of the study was to identify patterns of changes in the concentrations of hydrogen (H₂), methane (CH₄) and acetylene (C₂H₂) over time and to determine their diagnostic significance for the detection of thermal and electrical defects in the insulation system. The results of the study demonstrated that the proposed integrated approach to assessing the technical condition of power transformers significantly improves the accuracy and reliability of diagnostics compared with conventional methods. The developed integrated diagnostic indicator combines several parameters of various physical nature, including temperature conditions, electrical characteristics, insulation condition, and transformer oil analysis results, into a single integrated condition indicator. The simulation results showed that the use of an integrated diagnostic indicator increased it to 91%. The sensitivity was 0.89, and the F1-score was 0.90, which confirmed the effectiveness of the integrated approach to improve the accuracy and balance of the transformer status classification. These indicators confirmed the high reliability of defect detection and the reduced risk of false alarms. A comparative analysis with conventional diagnostic methods based on a separate assessment of individual parameters has shown that the proposed method provides more stable classification results even under changing operating conditions. The results obtained emphasised the practical significance of integrating statistical modelling, aggregation of multiparametric indicators, and analysis of gas dynamics into automated monitoring systems, which ultimately improves the quality of decision-making and the safety of operation of electric power systems
Keywords
References
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