Investigation on the possibility of silent partial discharges inside power transformers

摘要

The probability of creation of so called Silent-PDs is investigated by using a special configuration consisting of aramid papers impregnated with Midel 7131. A Needle-plane electrode arrangement is implemented to simulate the electrical stress on the surface of the insulation material. To record the acoustic emission (AE) signals from different sensors, they are mounted on the outside of a sample-tank. Based on the results achieved with this setup, reasons for the appearance of these kinds of discharges are discussed.