Since the first attempts to the automation of the assessment of FRA results, the necessity of dividing the frequency spectrum into sub-bands has been recognized as approach that enhances the reliability of the assessment. At the present, frequency sub-bands at fixed frequencies are used for the computation of statistical indicators (e.g. correlation coefficients) under which the automatic assessment is based. Even when the structure of the FRA plot of transformers can be somewhat generalized, it is important to take into account that the frequencies at which the sub-bands take place are specific to each winding and hence, it is very meaningful to develop algorithm for identification of transformer specific sub-bands. In this contribution, sub-band identification algorithms are presented and formulated as basis for a reliable and automatic assessment of FRA results. The implementation of these algorithms has shown satisfactory results.
Keywords: FRA; frequency sub-bands; assessment; transformers
Conference on Condition Monitoring and Diagnosis 2010 (CMD2010). Tokyo, Japan, 6-11 September 2010
Published: September 2010.