The AE-150 provided the position of the PD sources inside the transformer by detection of the mechanical behavior [acoustic] and electrical behavior [electro magnetic wave] of partial discharge phenomena. The 150/200/250 MVA power transformer is suspected that there is the PD inside. Therefore, the PD measurement was taken to local the PD source.
First, the transformer inspection was taken to determine dimension, position of the sensors.
By the measurement, the PRPD was done to obtain suspected PD signal on that position. Then on the position#2, the suspect PD was detected by AE sensors and HFCT sensor.
Next, the trigger set on the acoustic channel #4 clear denoised waveform were obtained. A closer zoom on the acoustic channels is clearly showing that channel #3 is the first to capture acoustic signal. This gives us the information that the source is located on the lower left side of the unit.