Fault Diagnosis of Oil-Immersed Power Transformer: A Case Study

This paper presents the assessment of fault severity within power transformers from Dissolved Gas Analysis (DGA) using Hydrocarbon(HC) Gas Score and Normalized Energy Intensity(NEI) score. The score enables it to indicate that the transformer is in a normal or abnormal state. Based on the score data, engineers can decide on which action to take on each transformer. The example case uses the DGA results of the transformer of a commercial building to assess the severity of the faults in the transformers according to the above scoring method.