Low-cost frequency response analyzer for transformer diagnosis

Frequency response analysis (FRA) is a powerful and sensitive tool to assess the core, windings and clamping structures within power transformer. In this paper, it represents a Low-Cost Frequency Response Analyzer (LCFRA). The developed LCFRA was composed of digital oscilloscope, function generator and Labview software. In this paper, the measured sampling was 22kV/400V 250kVA 3phase transformer. Then, the frequency response of transformer measured by the LCFRA was compared with that from commercial SFRA (DOBLE M5300). The results of LCFRA were similar to that of the commercial SFRA. This relation was proved by the cross correlation coefficients (CCF) which had the minimum value at 0.9976. This CCF value showed a good match relation between those two results.