| 摘要 |
PURPOSE: An internal defect diagnosis method of an oil immersed transformer is provided to accurately diagnose an internal defect of the oil immersed transformer using a dissolved gas composition ratio in the internal defect of the oil immersed transformer. CONSTITUTION: An internal defect diagnosis method of an oil immersed transformer which diagnoses an internal defect by extracting and analyzing dissolved gas comprises a first step (S205) which calculates CH4/H2 and C2H2/CH4 from the extracted dissolved gas; and a second step (S207) which determines whether the internal defect is partial discharge (PD) or energy discharge between a thermal defect, an electric defect corresponding the CH4/H2 and C2H2/CH4 to a predetermined internal defect area. [Reference numerals] (AA) Start; (BB) Finish; (S201) Detect dissolved gases of an oil immersed transformer desired to diagnose internal defects; (S203) Measure H2, CH4, C2H2, C2H4, and C2H6; (S205) Calculate content ratios of CH4/H2, C2H2/CH4, C2H4/C2H6, and C2H2/C2H4; (S207) Determine the internal defects of the oil immersed transformer by the values of CH4/H2, C2H2/CH4, C2H4/C2H6, and C2H2/C2H4 |
