Partial discharge study in transformer oil using acoustic emission technique and UV-visible spectroscopy

The existence of incipient faults in the transformer is realized in the degradation of the insulating transformer oil (TO). One of such incipient faults is partial discharge (PD). Even though PD problem looks small at the outset, if not taken care, it may lead to the major problem even to the extent of the total failure of the transformer. There are many methods that have come up to solve the partial discharge problem such as electrical measurement method, UHF (ultra-high frequency) antenna method, but they face the issue of noise interference. Therefore, in this proposed work, the attention has been drawn to acoustic emission (AE) technique. The obtained results show AE technique has great potential to analyze the PD activity efficiently with minimum background noise. This technique has several advantages over the conventional electrical method (IEC 60270) such as immune to electromagnetic interference, high monitoring sensitivity and the possibility of the detecting as well as locating the partial discharge. The proposed work also has been focused on the UV-visible spectroscopy to analyze the degraded oil samples due to PD. The obtained results showed that UV-visible spectroscopy has the potential to analyze PD-affected transformer oil samples qualitatively.