abstract = "Dissolved gas analysis (DGA) has been widely used for
the detection of incipient faults in oil-filled
transformers. This research presents a novel approach
to DGA feature prioritisation and classification, which
considers not only the relations between a fault type
and specific gas ratios but also their statistical
characteristics based on data derived from on site
inspections. Firstly, new gas features are acquired
based on the analysis of current international gas
interpretation standards. Combined with conventional
gas ratios, all features are then prioritised by using
the Kolmogorov-Smirnov test. The rankings are obtained
by using their values of maximum statistic distance.
The first three features in ranking are employed as
input vectors to a multi-layer support vector machine,
whose tuning parameters are acquired by particle swarm
optimisation. In the experiment, a bootstrap technique
is implemented to approximately equalise sample numbers
of different fault cases. A common 10-fold
cross-validation technique is employed for performance
assessment. Typical artificial intelligence classifiers
with gas features extracted from genetic programming
are evaluated for comparison purposes.",
notes = "Dept. of Electr. Eng. & Electron., Univ. of Liverpool,
Liverpool, UK