This thesis reports on research into intelligent partial discharge (PD)
diagnosis for turbogenerator condition monitoring (CM). PD activities
occurring in generator stator windings and modern techniques for PD CM
are introduced. Research is focused on graphical classification methods,
especially for small-size, and incomplete PD database. The research work
begins with study on feature extraction methods on different PD
patterns, and automated pattern recognition methods involving
conventional classifiers and neural networks. Laboratory tests are made
to observe PD activities and produce PD database containing typical PD
types on industrial model bars. A Hybrid Clustering Method (HCM) and an
advanced Self-Organizing Map (SOM) are presented to provide graphical
classification results where the relationship of new PD samples and
historical samples can be visualized. The work confirms that the
graphical classification methods can be used individually or combined
with other methods to provide reliable diagnostic information.