MODERN APPROACH FOR CONDITION MONITORING OF POWER TRANSFORMERS USING DISSOLVED GAS ANALYSIS
The transformer oil plays very important role to maintain healthy operating condition of transformer. When any fault occurs in the transformer due to different effects the formation of different gases takes place in the transformer oil. Dissolved Gas Analysis (DGA) has most proved accuracy method for condition assessment of power transformer. This gives prior information regarding mineral oil degradation level and generated dissolved gasses in mineral oil and concentration of dissolved gases by
... dissolved gases by using Gas Chromatography. Taking the concentration of key gases (CO, CO2, CH4, C2H6, C2H2, H2 and C2H4) incident faults identified by various classical techniques gives different conditions for the same sample unit. In this work considered the point, which discussed in above line and design combine of all five diagnosis methods for better accuracy results to diagnosis of incipient faults. There are more than 6 known different methods of DGA fault interpretation technique. Every method varies according to their techniques. A series of combined interpretation methods that can determine the power transformer condition faults in one assessment is therefore needed. This paper presents to combine five DGA assessment techniques; Doernenburg Ratio Method Rogers Ratio Method, IEC Basic Ratio Method, Duval Triangle method and Key Gas Method.