Frequency-response analysis of power transformers by means of fuzzy tools

A novel Fuzzy algorithm for the automatic analysis of frequency response of power transformers is described in this paper. It relies on the values of two parameters able to quantify the difference between the present and a reference frequency response, over three frequency ranges. These ranges are associated with different defect types, i.e., short circuits between turns, radial and axial displacements. Training examples obtained mainly from experimental results have been used to select the different ranges. Fuzzy-Logic has been adopted to reflect the uncertainty in the analysis of the differences between the two curves in the defect-identification results. Practical applications are also discussed to show the efficiency of the proposed diagnostic method.