Review of Sweep Frequency Response Analysis -SFRA for Assessment Winding Displacements and Deformation in Power Transformers

The Sweep Frequency Response Analysis SFRA is a diagnostic technique for detecting winding displacement and deformation (among other mechanical and electrical failures) on power and distribution transformer in which the diagnosis relies on experts´ knowledge. SFRA as a diagnostic technique must integrate both the off-line measurements and the interpretation of the data in order to provide a assessment to the condition of the windings, however there is not a guideline for the measurement and the process of interpretation the records has not been defined. This paper presents a revision about the variants in the metrology and interpretation of the SFRA measurements.