There are two thought trends concerning partial
discharge, PD, measurements and diagnostics in electrical
insulation systems. One is make it simple and refer to PD
amplitude and repetition rate. The other is try to identify the
typologies of discharges and focus on each type of source
generating PD for diagnostic and maintenance decisions. In this
paper, an approach towards the determination of a health index
for rotating machines is presented. It is based on the harmfulness
of typical defects able to generate PD and, hence, on the capability
of the detection system (sensor, filters, PD detector, software) to
provide efficient noise rejection and/or noise and PD source
identification. The output, that is, the global health index, is
thought to be helpful to support maintenance manager decisions
about the actions which may be needed to keep reliability of a
rotating machine at the desired level, and also to evaluate in terms
of cost/effectiveness the potential maintenance actions.
