DISSOLVE GAS ANALYSIS OF AGED TRANSFORMER OIL: A CASE STUDY

Abstract

Insulating oil of the transformer plays important role by serving several purposes like dielectric media, an insulator, helps to extinguish arcs as well as heat transfer agent between the conductors and cooling medium inside the transformer. During continuous long period of operation, transformers are subject to huge thermal and electrical stresses, which degrade the insulating oil and leads catastrophic failure of transformer, hence failure in power system network. The degradation of such transformer oil produces different kinds of gases as byproducts which entirely or partially dissolve in the transformer oil and the quality of dielectric strength of insulating oil is degrading. The dissolved gas analysis (DGA) is popularly recognized as most useful and predictive maintenance tool for condition monitoring of transformer health. In this work, an Infrared photo-acoustic spectroscopy technique is used for dissolve gas analysis of three different distribution transformer oil sample for finding out the fault gas. Finally, observed practical results are tested with developed software in MATLAB environment for validation of fault gases representation using Duval Triangle method.