Analysis results of partial discharges (PD) measurements
within a power transformer situated in a testing station, carried out by the
so-called joint electro-acoustic method, is presented in the paper. Basing
on measurements resultant from the electric method apparent charge values at
different test voltage levels have been determined. Such charges are
introduced by PD sources within one of three phases of high-voltage winding
whereas two remaining phases are shorted and grounded. An analysis of
acoustic emission (AE) measurement results allows us: to identify the main
band of other acoustic phenomena (Barkhausen's acoustic effect,
magnetostrictive phenomena, noises connected with circulation of the oil and
other noises), to show the local character of PD measurements coming from AE
method, to identify AE signals characterized by maximum value of ADC
descriptor, to locate measuring points on the tank for mentioned signals.
The correlation between apparent charge values in particular phases and ADC
descriptor values (as maximum ones in AE signal sets, recorded at different
measuring points for respective phases) is managed to settle.