YUAN Lei1, DU Lin2, WU Jun-mei1, et al. Transformer Multi-parameter Integrated Fault Diagnosis Method Based on Fuzzy Membership Function[J]. High voltageapparatus, 2011, 47(5): 35-42.
Oil-immersed power transformers is the most critical devices of power system
and its failure diagnosis technology is deeply concerned.By analyzing a variety of data which reflect the current transformer operation conditions and according to the current transformer fault monitoring and maintenance status in power enterprises
a relationship between failure characteristic parameters and corresponding failure modes was established based on the structure of power transformers.Fuzzy mathematical method was employed to analyze the membership function of different electric test for transformer failure mode
hence the fixity and subjectivity in selection of the membership function and its parameters were overcome.The dissolved gas was first analyzed by three-ratio method to find the cause of fault
and then the fault probability was determine by the distance between the original to the coordinate fault point.Furthermore
by combining the characteristics of various parameters and introducing the gray correlation analysis to determine their weights
the fault probability of a transformer can be evaluated via the comprehensive diagnostic model.The examples show that this method is simple and accurate.