The study of sweep frequency response analysis for inspecting the performance of transformer

Abstract

Transformer had been widely used for supplying electric power to many motors, such as electric pump, fans, or conveyors. The motor voltage may vary that is depending on its power and speed between one to another motor. The load needs the transformer which generate the proper voltage. Unfortunately, the working performance of transformer is slowly decreasing because of its daily operation. The repetition of the transformer technical assessment by observing the transformer performance is needed. This study provides the periodical inspection of high-power transformer in maintenance and outage condition in the one of utility sites in Indonesia. The checking activity maintenance the eligible performance of the user device. The measurement of Sweep Frequency Response Analysis (SFRA) in the 5th unit had been inspected once in every six years. The measured result was obtained in 2007 and 2013. SFRA test diagnoses the characteristics of transformer winding and core by injecting low voltage at a certain frequency. If SFRA diagnoses the winding fault, then the transformer should be replaced or should get a major maintenance. The result of SFRA measurement provides the transformer winding and core still in a good condition because the shrinkage does not exceed 20% of its standard percentage. Therefore, the 500 kV power transformer, located in PT. YTL East Java, does not have to get serious maintenance.