FAULT DIAGNOSIS METHOD OF OIL FILLED TRANSFORMER USING PROPORTION RATIO OF DISSOLVED GASES

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 comprises a first step (S203) which extracts H2, CH4, C2H4, C2H2 and C2H6 among dissolved gases; a second step (S207) which selects four dissolved gases divided by an internal defect among five dissolved gases and calculates a content ratio (%) in which each dissolved gas among every contents of the four dissolved gases occupies; and a third step (S209) which determines the internal defect of an oil immersed transformer corresponding to an internal defect area according to the content ratio (%) of the calculated four dissolved gases and the content ratio of the predetermined four dissolved gases. [Reference numerals] (AA) Start; (BB) Finish; (S201) Detect dissolved gases of an oil immersed transformer desired to diagnose internal defects; (S203) Measure H2, CH4, C2H4, C2H2 and C2H6; (S205) Select four dissolved gases divided by an internal defect among five dissolved gases; (S207) Calculate %H2, %CH4, %C2H4, and %C2H2 in respect to the whole content of the four dissolved gases; (S209) Determine the internal defects of the oil immersed transformer by the calculated values of %H2, %CH4, %C2H4 and %C2H2