Implementation of the SFRA method as valuable tool for detection of power transformer active part deformation

Abstract

The paper presents the SFRA (Sweep Frequency Response Analysis-SFRA) method for analyzing frequency response of transformer windings in order to identify potential defects in the geometry of the core and winding. The most frequent problems (recognized by SFRA) are: core shift, shorted or open winding, unwanted contact between core and mass, etc. Comparative analysis of this method with conventional methods is carried out in situ transformer in real hard industrial conditions. Benefits of SFRA method are great reliability and repeatability of the measurements. This method belongs to the non-invasive category. Due to the high reliability and repeatability of the measurements it is very suitable for detection of changes in the geometry of the coil and the core during prophylactic field testing, or after transporting the transformer.

Keywords

• SFRA method
• frequency response analysis
• power transformer
• winding deformation