An overview of the On Line Application of Frequency Response Analysis (FRA)

This paper provides an overview of on line application of frequency response analysis technique, this mean, without needing to interrupt the power supply. The electric utility industry is in the age of transition from periodic maintenance to condition based maintenance on essential substation power transformers in an effort to lower maintenance costs and maximize the use of existing equipment. The development of on-line diagnostics is in the critical path to achieve the condition based maintenance goal for power transformers. However, it is not clear how to deal with this project and multiple proceedings are possible. According to FRA, there is not a well establish procedure to develop the maintenance technique. This paper tries to show different methods and future trends to carry out the FRA measurements without disconnecting the transformer.