  The work proposes the application of fuzzy set theory (FST) to diagnose the
condition of high voltage bushings. The diagnosis uses dissolved gas analysis
(DGA) data from bushings based on IEC60599 and IEEE C57-104 criteria for oil
impregnated paper (OIP) bushings. FST and neural networks are compared in terms
of accuracy and computational efficiency. Both FST and NN simulations were able
to diagnose the bushings condition with 10% error. By using fuzzy theory, the
maintenance department can classify bushings and know the extent of degradation
in the component.
