Abstract:

The Dissolved Gas Analysis (DGA) and partial discharge (PD) level measurement are important tools for evaluating the condition of the insulation of a transformer, which is an indicator of the health of a transformer and cam help in prevention of the transformer failure. In this paper the PD level and dissolved hydrogen (H2) and acetylene (C2H2) gases in oil of an artificially aged/ stressed insulation system of a specially designed test cell have been analyzed and compared with the results of the experimental studies. Considering the various formulae existing in literature for the dependence of PD on applied voltage in high voltage equipment, regression analysis has been done. On analyzing the content of dissolved H2 and C2H2 gases in the oil, with the PD measurements, incipient conditions of PD and low energy arcing within a transformer can be used to distinguish. This is useful for timely detection of insulation degradation.