Optical Frequency-Response Analysis for Power Transformer

An optical frequency-response analysis (OFRA) method is proposed to detect the winding deformation in a power transformer. Compared to existing frequency-response analysis (FRA) systems, the proposed system has several unique merits, such as high immunity to electromagnetic interference, direct display of winding deformation, no influence of connected power equipment, and long reliability in harsh environments. First, the principle of optical frequency-response detection and noise elimination is introduced. Then, the algorithm used to acquire the winding deformation matrix is discussed in detail. Next, winding deformation experiments are carried out to investigate the diagnostic ability of the proposed OFRA method. The experimental results indicate that the OFRA can locate the deformation disc and determine the deformation level correctly.