Sweep Frequency Response Analysis for Assessment of Abnormalities in Power Transformer

Abstract

For beneficial generation and transmission of electrical power trustworthy and continued performance of power transformer is necessary. Failure of large power transformer can cause serious damage as well as loss of very expensive equipment. If failure is not disastrous their replacement can take a year and can results in formidable revenue losses and fires as they are most valuable asset in power system. Therefore in order to reduce associated cost after its failure diagnosis of this equipment becomes more relevant. Regarding data acquisition, various aspects of measurement and analysis many technical advancement took place during last few years. Transformer is submitted to many short circuits during its life with high fault currents, which consequently, may cause deformations and displacements of windings as well as changes to winding inductance or capacitance in transformers. Through the traditional condition monitoring techniques, such as dissolved gas analysis, winding resistance measurements, capacitance and tan delta measurements etc. such small movements cannot be detected. Hence for condition monitoring of power transformer sweep frequency response analysis is essential.